Excitation of the Isovector Spin Monopole Resonance via the Exothermic

The (^{12}N, ^{12}C) charge-exchange reaction at 175 MeV/u was developed as a novel probe for studying the isovector spin giant monopole resonance (IVSMR), whose properties are important for better understanding the bulk properties of nuclei and asymmetric nuclear matter. This probe, now available through the production of ^{12}N as a secondary rare-isotope beam, is exothermic, is strongly absorbed at the surface of the target nucleus, and provides selectivity for spin-transfer excitations. All three properties enhance the excitation of the IVSMR compared to other, primarily light-ion, probes, which have been used to study the IVSMR thus far. The ^{90}Zr(^{12}N,^{12}C) reaction was measured and the excitation energy spectra up to about 70 MeV for both the spin-transfer and non-spin-transfer channels were deduced separately by tagging the decay by γ emission from the ^{12}C ejectile. Besides the well-known Gamow-Teller and isobaric analog transitions, a clear signature of the IVSMR was identified. By comparing with the results from light-ion reactions on the same target nucleus and theoretical predictions, the suitability of this new probe for studying the IVSMR was confirmed.

Observation of the Isovector Giant Monopole Resonance via the

The (^{10}Be,^{10}B^{*}[1.74 MeV]) charge-exchange reaction at 100 AMeV is presented as a new probe for isolating the isovector (ΔT=1) nonspin-transfer (ΔS=0) response of nuclei, with ^{28}Si being the first nucleus studied. By using a secondary ^{10}Be beam produced by fast fragmentation of ^{18}O nuclei at the NSCL Coupled Cyclotron Facility, applying the dispersion-matching technique with the S800 magnetic spectrometer to determine the excitation energy in ^{28}Al, and performing high-resolution γ-ray tracking with the Gamma-Ray Energy Tracking In-beam Nuclear Array (GRETINA) to identify the 1022-keV γ ray associated with the decay from the 1.74-MeV T=1 isobaric analog state in ^{10}B, a ΔS=0 excitation-energy spectrum in ^{28}Al was extracted. Monopole and dipole contributions were determined through a multipole-decomposition analysis, and the isovector giant dipole resonance and isovector giant monopole resonance (IVGMR) were identified. The results show that this probe is a powerful tool for studying the elusive IVGMR, which is of interest for performing stringent tests of modern density functional theories at high excitation energies and for constraining the bulk properties of nuclei and nuclear matter. The extracted distributions were compared with theoretical calculations based on the normal-modes formalism and the proton-neutron relativistic time-blocking approximation. Calculated cross sections based on these strengths underestimate the data by about a factor of 2, which likely indicates deficiencies in the reaction calculations based on the distorted wave Born approximation.

Candidate Resonant Tetraneutron State Populated by the

A candidate resonant tetraneutron state is found in the missing-mass spectrum obtained in the double-charge-exchange reaction ^{4}He(^{8}He,^{8}Be) at 186 MeV/u. The energy of the state is 0.83±0.65(stat)±1.25(syst) MeV above the threshold of four-neutron decay with a significance level of 4.9σ. Utilizing the large positive Q value of the (^{8}He,^{8}Be) reaction, an almost recoilless condition of the four-neutron system was achieved so as to obtain a weakly interacting four-neutron system efficiently.

Nonquenched Isoscalar Spin-M1 Excitations in sd-Shell Nuclei.

Differential cross sections of isoscalar and isovector spin-M1 (0(+)→1(+)) transitions are measured using high-energy-resolution proton inelastic scattering at E(p)=295 MeV on (24)Mg, (28)Si, (32)S, and (36)Ar at 0°-14°. The squared spin-M1 nuclear transition matrix elements are deduced from the measured differential cross sections by applying empirically determined unit cross sections based on the assumption of isospin symmetry. The ratios of the squared nuclear matrix elements accumulated up to E(x)=16 MeV compared to a shell-model prediction are 1.01(9) for isoscalar and 0.61(6) for isovector spin-M1 transitions, respectively. Thus, no quenching is observed for isoscalar spin-M1 transitions, while the matrix elements for isovector spin-M1 transitions are quenched by an amount comparable with the analogous Gamow-Teller transitions on those target nuclei.

Identification of the ß+ isovector spin monopole resonance via the 208Pb and 90Zr(t,3He) reactions at 300 MeV/u.

The double-differential cross sections for the (208)Pb and (90)Zr(t,(3)He) reactions at 300 MeV/u have been measured at the RI Beam Factory at RIKEN. This was the first physics experiment with the SHARAQ magnetic spectrometer. The combined analysis of the present (t,(3)He) data and previous (n,p) data provides the clearest identification for the ß(+) isovector spin monopole resonance both in the (208)Tl and (90)Y nuclei, and puts the observations of this giant resonance on a firm foundation. The measured distributions of the (t,(3)He) monopole cross sections were well reproduced by the distorted-wave Born approximation calculation, where the target transition density was calculated with the self-consistent Hartree-Fock plus random-phase approximation using the T43 Skyrme interaction. A major part of the expected ß(+) isovector spin monopole strength was found in the measured cross section spectra.

Complete electric dipole response and the neutron skin in 208Pb.

A benchmark experiment on (208)Pb shows that polarized proton inelastic scattering at very forward angles including 0° is a powerful tool for high-resolution studies of electric dipole (E1) and spin magnetic dipole (M1) modes in nuclei over a broad excitation energy range to test up-to-date nuclear models. The extracted E1 polarizability leads to a neutron skin thickness r(skin) = 0.156(-0.021)(+0.025) fm in (208)Pb derived within a mean-field model [Phys. Rev. C 81, 051303 (2010)], thereby constraining the symmetry energy and its density dependence relevant to the description of neutron stars.

Gamow-Teller strength distributions in 48Sc by the 48Ca(p,n) and 48Ti(n,p) reactions and two-neutrino double-beta decay nuclear matrix elements.

The double-differential cross sections for the 48Ca(p,n) and 48Ti(n,p) reactions were measured at 300 MeV. A multipole decomposition technique was applied to the spectra to extract the Gamow-Teller (GT) components. The integrated GT strengths up to an excitation energy of 30 MeV in 48Sc are 15.3+/-2.2 and 2.8+/-0.3 in the (p,n) and (n,p) spectra, respectively. In the (n,p) spectra additional GT strengths were found above 8 MeV where shell models within the fp shell-model space predict almost no GT strengths, suggesting that the present shell-model description of the nuclear matrix element of the two-neutrino double-beta decay is incomplete.

Fate of cystic ovarian follicles and the subsequent fertility of early postpartum dairy cows.

The fate of cystic ovarian follicles that developed spontaneously during the early postpartum period of 50 lactating dairy cows was traced by ultrasonography to characterise the follicular dynamics in relation to the fertility of the cows. The absence of postpartum ovulations caused by repeated waves of anovulatory large follicles was also characterised and evaluated. Fifteen of the 50 cows developed cystic follicles, and these follicles became follicular cysts in five of the 15 cows. Most of the cystic follicles emerged before the first postpartum ovulation of the cows. The transition from cystic follicles to follicular cysts delayed the cows' first ovulation, oestrus and insemination, but had less influence on their fertility after they had recovered spontaneously. In addition to the 15 cows that developed cystic follicles or follicular cysts, six of the cows had five to 13 waves of follicles before their first ovulation. These repeated waves of follicles caused a more severe delay in the early postpartum reproductive events but did not affect the cows' fertility.

Postpartum ovarian follicular dynamics and estrous activity in lactating dairy cows.

The objectives of this study were to characterize early postpartum follicular dynamics in dairy cows in relation to their estrual activity and subsequent reproductive performance using 50 (26 primiparous and 24 multiparous) lactating Holstein cows. Ovaries and uterine horns of postpartum lactating cows were examined by ultrasonography 3 times weekly and continued until first services occurred after a 45-d voluntary waiting period. No differences were detected in fertility between primiparous and multiparous cows. In 40 of 50 cows, first postpartum ovulation was observed within 4 follicular waves, and the follicular wave patterns and ovarian cycles in most cows returned to normal as in cattle having normal estrous cycles after the second postpartum ovulation. Cows with the longest intervals from calving to first ovulation produced the most milk and also had prolonged intervals to first estrous activity. Differences in follicular dynamics before first ovulation altered intervals to first estrus, first service, and uterine involution, but these differences did not affect pregnancy rate, number of services, and days open. First postpartum insemination after 3 follicular waves tended to have greater pregnancy rates than those after 2 follicular waves. First inseminations at first estrus could produce greater pregnancy rates than those at subsequent periods of estrus.

Effects of bright light at lunchtime on sleep of patients in a geriatric hospital I.

The effects of lunchtime bright light exposure in patients of a geriatric hospital were investigated. Ten inpatients (six women and four men; mean age +/- SD: 81.2 +/- 8.8 years) with sleep disturbances were studied for 9 weeks. Nurses performed daily ratings for sleep-wakefulness disturbances. Approximately 8000 lx bright light exposure was performed for 3 weeks in the light therapy room. Before and after exposure, ocular function was evaluated. Clinical ratings of sleep-wakefulness improved in eight patients. The score of difficulty in falling asleep and drowsiness in the morning declined during the light exposure. The score of drowsiness in the afternoon decreased during the post-light exposure. Post-exposure ocular disturbances were not found.

Effects of bright light at lunchtime on sleep in patients in a geriatric hospital II.

Inpatients with sleep disturbances in a geriatric hospital received 1 h of exposure to approximately 8000 lx bright light per day for 3 weeks. Polysomnogram was recorded for four female patients. Two (aged 68 and 87 years) were non-demented patients with weak cataracts and the other two (aged 92 and 93 years) were demented patients with severe cataracts. Electroencephalogram results showed that light exposure decreased the proportion of Stage W, while increased the proportion of Stage 2, and these effects continued for at least 3 weeks after the cessation of light exposure. These results suggest that exposure to bright light is effective in improving the disturbed sleep of patients.

Amelioration of experimental autoimmune uveoretinitis by pretreatment with a pathogenic peptide in liposome and anti-CD40 ligand monoclonal antibody.

We have defined a peptide K2 (ADKDVVVLTSSRTGGV) that corresponds to residues 201-216 of bovine interphotoreceptor retinoid-binding protein and induces experimental autoimmune uveoretinitis (EAU)4 in H-2Ak-carrying mice (H-2Ak mice). In this study, we attempted to ameliorate EAU in the H-2Ak mice without nonspecific suppression of T cell responses. Preceding s.c. administration of liposomes including K2 (liposomal K2) specifically inhibited subsequent generation of T cell response to K2. The same result was obtained with a combination of OVA323-339 peptide and the OVA-specific TCR-transgenic T cells. It was suggested that the inhibition was mainly attributed to peripheral anergy induction of T cells specific for the peptide Ag, although specific cell death might also be involved in the inhibition. Pretreatment with liposomal K2 also considerably abolished IFN-gamma production but not IL-4 production. The specific inhibitory effect of the pretreatment with liposomal peptide was augmented by a simultaneous administration of anti-CD40 ligand (anti-CD40L) mAb. Moreover, it was shown that the pretreatment with liposomal K2 reduced both the incidence and severity of the subsequent K2-induced EAU, and the simultaneous administration of anti-CD40L mAb augmented this preventive effect by liposomal K2. Our findings demonstrate that the s.c. administration of liposomal pathogenic peptide and anti-CD40L mAb can be applied to preventing autoimmune diseases without detrimental nonspecific suppression of T cell responses.

Inhibition of experimental autoimmune uveoretinitis with anti-macrophage migration inhibitory factor antibodies.

PURPOSE: The role of macrophage migration inhibitory factor (MIF) in the regulation of ocular autoimmune disease was studied in experimental autoimmune uveoretinitis (EAU) in rats following immunization with a retinal antigen (Ag), interphotoreceptor retinoid-binding protein (IRBP). METHODS: LEW rats were immunized with a single injection of IRBP derived peptide, R16(ADGSSWEGVGVVPDV). A neutralizing monoclonal antibody (mAb, IgM) to MIF was injected intraperitoneally every second day from day 0 to day 6 (group A), or from day 8 to day 14 (group B). Control rats were treated with unrelated mouse IgM or PBS. T cell proliferative responses were measured 12 days after immunization. The occurrence and severity of EAU were observed and compared among experimental and control groups. RESULTS: T cell proliferative responses against R16 were inhibited in rats treated with anti-MIF mAb compared with the control rats. The development of EAU was delayed in the rats of group A in comparison with those of group B and the control group. The mean histological EAU score on day 18 in group A was 1.11 +/- 0. 11 and significantly lower than those of the group B (1.29 +/- 0.19) and the control (1.67 +/- 0.19). CONCLUSIONS: The present result suggests that MIF plays an important role in induction of EAU.

High-dose corticosteroid administration induces increase of serum macrophage migration inhibitory factor in patients with Vogt-Koyanagi-Harada's disease.

To investigate the influence of corticosteroid administration on the serum level of macrophage migration inhibitory factor (MIF), sera obtained from 9 patients with Vogt-Koyanagi-Harada's disease who had been treated with high-dose corticosteroid were analyzed. The serum MIF levels of most patients were prominently increased on day 7 and/or day 14 after corticosteroid treatment. No TNF-alpha was detected in the sera. The average serum MIF level of nine patients at the highest stages after corticosteroid administration was significantly higher than that before the corticosteroid treatment. It seems that MIF is a unique cytokine and acts together with corticosteroid to regulate inflammation and immunity.

[Observation of physiological change in the human ciliary body using an ultrasound biomicroscope during accommodation].

PURPOSE: To evaluate changes in the ciliary body during accommodation using an ultrasound biomicroscope (UBM). SUBJECTS AND METHODS: Eleven healthy persons, aged from 24 to 33 years, served as subjects. They were asked to lie in the supine position and to fixate a target placed on the ceiling 2 m above with the left eye. A concave lens with the power of -6 to -8 diopters was then placed before the fixating left eye. The thickness of the ciliary body in the right eye was measured by UBM in the nonaccommodative and accommodative states. FINDINGS: The anterior chamber in the right eye became significantly shallow during accommodation. The thickness of the ciliary body significantly increased during accommodation at 0.5 mm and 1.0 mm posterior to the scleral spur. It significantly decreased at 2.0 mm, 2.5 mm and 3.0 mm posterior to the scleral spur. CONCLUSION: During induced accommodation in the left eye, the anterior portion of the ciliary body in the right eye increased and the posterior portion decreased in thickness. The findings imply that the circular ciliary muscles are mainly involved in accommodation and not the longitudinal muscles.

Central nervous system symptoms in patients with Behçet disease receiving cyclosporine therapy.

OBJECTIVE: To investigate the association between the development of central nervous system (CNS) symptoms in patients with Behçet disease and medical therapy. DESIGN: Retrospective cohort study. PARTICIPANTS: A total of 317 patients with Behçet disease with ocular complications who visited Hokkaido University Hospital, Sapporo, Japan, between 1978 and 1994. MAIN OUTCOME MEASURES: The incidence of CNS symptoms in different medical therapies. RESULTS: Twenty-one (6.6%) of the 317 patients developed CNS symptoms, namely neuro-Behçet disease. Of the 21 patients, 12 were undergoing cyclosporine therapy. Of the 47 patients who underwent cyclosporine therapy, 12 (25.5%) developed CNS symptoms, whereas only 9 (3.3%) of 270 patients who did not undergo cyclosporine therapy developed CNS symptoms. CONCLUSIONS: Cyclosporine in the treatment of Behçet disease appears to cause neurotoxicity or to accelerate the development of CNS symptoms. Thus, neurologic complications appear to represent a major side effect of cyclosporine in the treatment of patients with Behçet disease.

Prominent increase of macrophage migration inhibitory factor in the sera of patients with uveitis.

PURPOSE: To investigate pathogenesis underlying endogenous uveitis, macrophage migration inhibitory factor (MIF) was quantified in sera of patients. METHODS: Sera were obtained from the 55 patients with uveitis (24 with Behçet's disease; 9 with Vogt-Koyanagi-Harada's [VKH] disease; 22 with sarcoidosis) and 58 healthy control subjects. MIF levels were determined by a human MIF enzyme-linked immunosorbent assay. RESULTS: The mean MIF levels in the sera of the patients with Behçet's disease, VKH disease, and sarcoidosis and of healthy control subjects were 60.4+/-9.0 (mean+/-SE) ng/ml, 16.5+/-2.9 ng/ml, 27.1+/-5.6 ng/ml, and 5.4+/-0.04 ng/ml, respectively. The average levels of MIF in the sera of uveitis patients were significantly higher (P < 0.0001) than those of healthy control subjects. The high levels of MIF were especially noted in patients with Behçet's disease at the ocular exacerbation stage and patients with sarcoidosis at the severe uveitis stage. CONCLUSIONS: Significant increase of MIF in sera was characteristic of uveitis, and MIF may be a usefull laboratory parameter to use to comprehend the clinical course of uveitis.

The development of malignant rhabdoid tumor in a patient with Behçet's disease treated with ciclosporin.

PURPOSE: To describe a risk of malignant neoplasm in patients with Behçet's disease treated with ciclosporin. METHODS: Case report. RESULTS: A patient with Behçet's disease who was treated with ciclosporin developed a mass in his right femur. Histological examination revealed this mass was a malignant rhabdoid tumor. CONCLUSION: This is the first known case of malignant tumor developing in a patient with Behçet's disease treated with ciclosporin. This case underscores the importance of assessing possible risks in the treatment of Behçet's disease with ciclosporin.

Effects of short duration morning bright light in healthy elderly subjects. I: subjective feeling and ophthalmological examinations.

Seven aged subjects aged 61-78 years were exposed to 6000 lx bright light for 30 min during morning hours at their homes for 1 week. Visual analog scale was recorded before bedtime and after rising to assess subjective feelings. Ophthalmological examinations were made before and after light exposure, to exclude pre-existing ocular disorders and to detect ocular damage. Furthermore, ocular fatigue was self-evaluated immediately before and after exposure. Visual analog scale results indicated that alertness reduced significantly before bedtime. Ophthalmological abnormalities were not found after exposure. These findings suggest that short duration morning bright light exposure reduces night-time vigilance.

Identification of a peptide inducing experimental autoimmune uveoretinitis (EAU) in H-2Ak-carrying mice.

When certain strains of mice bearing H-2Ak are immunized with the interphotoreceptor retinoid-binding protein (IRBP), EAU is induced. Thus far uveitogenic determinant(s) has not been determined in the H-2Ak mouse system. In addition it is hard to prepare purified IRBP. In the present study, to circumvent these problems we attempted to identify uveitogenic peptides derived from bovine IRBP in H-2Ak haplotype mice. Six peptides which had been selected according to the H-2Ak binding motif (Dxxxxxxxx[A, R, T]) were synthesized. We report here that all the peptides are immunogenic but only one peptide, K2, which consisted of IRBP201-216 residues, induces EAU in various mice carrying H-2Ak. Amino acid substitution of K2 revealed that the core region interacted with both H-2Ak and T cell antigen receptor (TCR). The amino acid sequence of the core region derived from bovine IRBP was identical to the corresponding region of mouse IRBP. In addition, K2 appeared to be a natural peptide antigen processed from bovine IRBP. Altogether, we concluded that K2 is one of the natural autoantigens involved in induction of EAU in H-2Ak mice.