Precise Spectroscopy of the 3n and 3p Systems via the

To search for low-energy resonant structures in isospin T=3/2 three-body systems, we have performed the experiments ^{3}H(t,^{3}He)3n and ^{3}He(^{3}He,t)3p at intermediate energies. For the 3n experiment, we have newly developed a thick Ti-^{3}H target that has the largest tritium thickness among targets of this type ever made. The 3n experiment for the first time covered the momentum-transfer region as low as 15 MeV/c, which provides ideal conditions for producing fragile systems. However, in the excitation-energy spectra we obtained, we did not observe any distinct peak structures. This is in sharp contrast to tetraneutron spectra. The distributions of the 3n and 3p spectra are found to be similar, except for the displacement in energy due to Coulomb repulsion. Comparisons with theoretical calculations suggest that three-body correlations exist in the 3n and 3p systems, although not enough to produce a resonant peak.

Publisher Correction: An increase in the 12C + 12C fusion rate from resonances at astrophysical energies.

In equation (1) of this Letter, the closing bracket was missing; in Extended Data Fig. 1 and the accompanying legend, 'Φ(pd)' should have been 'Φ2(pd)', and in the Methods the text "Odd J assignments are uncertain by ±1." has been added. These errors have all been corrected online.

An increase in the 12C + 12C fusion rate from resonances at astrophysical energies.

Carbon burning powers scenarios that influence the fate of stars, such as the late evolutionary stages of massive stars 1 (exceeding eight solar masses) and superbursts from accreting neutron stars2,3. It proceeds through the 12C + 12C fusion reactions that produce an alpha particle and neon-20 or a proton and sodium-23-that is, 12C(12C, α)20Ne and 12C(12C, p)23Na-at temperatures greater than 0.4 × 109 kelvin, corresponding to astrophysical energies exceeding a megaelectronvolt, at which such nuclear reactions are more likely to occur in stars. The cross-sections 4 for those carbon fusion reactions (probabilities that are required to calculate the rate of the reactions) have hitherto not been measured at the Gamow peaks 4 below 2 megaelectronvolts because of exponential suppression arising from the Coulomb barrier. The reference rate 5 at temperatures below 1.2 × 109 kelvin relies on extrapolations that ignore the effects of possible low-lying resonances. Here we report the measurement of the 12C(12C, α0,1)20Ne and 12C(12C, p0,1)23Na reaction rates (where the subscripts 0 and 1 stand for the ground and first excited states of 20Ne and 23Na, respectively) at centre-of-mass energies from 2.7 to 0.8 megaelectronvolts using the Trojan Horse method6,7 and the deuteron in 14N. The cross-sections deduced exhibit several resonances that are responsible for very large increases of the reaction rate at relevant temperatures. In particular, around 5 × 108 kelvin, the reaction rate is boosted to more than 25 times larger than the reference value 5 . This finding may have implications such as lowering the temperatures and densities 8 required for the ignition of carbon burning in massive stars and decreasing the superburst ignition depth in accreting neutron stars to reconcile observations with theoretical models 3 .

Precise Measurement of Differential Cross Sections of the Σ

The differential cross sections of the Σ^{-}p→Λn reaction were measured accurately for the Σ^{-} momentum (p_{Σ}) ranging from 470 to 650 MeV/c at the J-PARC Hadron Experimental Facility. Precise angular information about the Σ^{-}p→Λn reaction was obtained for the first time by detecting approximately 100 reaction events at each angular step of Δcosθ=0.1. The obtained differential cross sections show a slightly forward-peaking structure in the measured momentum regions. The cross sections integrated for -0.7≤cosθ≤1.0 were obtained as 22.5±0.68 [statistical error(stat.)] ±0.65 [systematic error(syst.)] mb and 15.8±0.83(stat)±0.52(syst) mb for 470

Possible involvement of regulatory T cell abnormalities and variational usage of TCR repertoire in children with autoimmune neutropenia.

Autoimmune neutropenia (AIN) in childhood is characterized by chronic neutropenia and positivity for anti-neutrophil antibodies, resulting in the excessive destruction of neutrophils. In this study, we investigated the involvement of regulatory T cells (Tregs ) in the pathogenesis of AIN in childhood. Tregs have been classified into three subpopulations based on the expressions of CD45RA and forkhead box protein 3 (FoxP3): resting Tregs , activated Tregs and non-suppressive Tregs . The frequency of activated Tregs (CD4+ CD25+ FoxP3high CD45RA- T cells) as well as that of total Tregs (CD4+ CD25+ FoxP3+ T cells) in peripheral blood was significantly decreased in patients with AIN. Analysis of the T cell receptor (TCR)-Vß repertoire of CD4+ T cells revealed skewed usages in patients with AIN compared with that observed in age-matched control subjects. Regarding T cell subsets, the use of four of 24 TCR-Vß families in Tregs and one in conventional T cells were increased in patients with AIN. The number of patients with AIN who showed skewed usages of TCR-Vß family in conventional and Tregs was significantly higher than that reported in control subjects. When the preference between Tregs and conventional T cells in each TCR-Vß family was individually compared, different use was prominently observed in the TCR-Vß 9 family in patients with AIN. These results suggest that the quantitative abnormalities of Tregs and the skew of the TCR-Vß repertoire in CD4+ T cells, including Tregs and conventional T cells, may be related to autoantibody production through a human neutrophil antigen-reactive T cell clone.

Advancement of Photospheric Radius Expansion and Clocked Type-I X-Ray Burst Models with the New

We report the first (in)elastic scattering measurement of ^{25}Al+p with the capability to select and measure in a broad energy range the proton resonances in ^{26}Si contributing to the ^{22}Mg(α,p) reaction at type I x-ray burst energies. We measured spin-parities of four resonances above the α threshold of ^{26}Si that are found to strongly impact the ^{22}Mg(α,p) rate. The new rate advances a state-of-the-art model to remarkably reproduce light curves of the GS 1826-24 clocked burster with mean deviation <9% and permits us to discover a strong correlation between the He abundance in the accreting envelope of the photospheric radius expansion burster and the dominance of ^{22}Mg(α,p) branch.

Observation of Coulomb-Assisted Nuclear Bound State of Ξ

In an emulsion-counter hybrid experiment performed at J-PARC, a Ξ^{-} absorption event was observed which decayed into twin single-Λ hypernuclei. Kinematic calculations enabled a unique identification of the reaction process as Ξ^{-}+^{14}N→_{Λ}^{10}Be+_{Λ}^{5}He. For the binding energy of the Ξ^{-} hyperon in the Ξ^{-}-^{14}N system a value of 1.27±0.21 MeV was deduced. The energy level of Ξ^{-} is likely a nuclear 1p state which indicates a weak ΞN-ΛΛ coupling.

Occurrence of noroviruses in recycled water and sewage sludge: emergence of recombinant norovirus strains.

AIMS: To investigate the presence of noroviruses in recycled water and sewage sludge obtained from a wastewater treatment plant in Bangkok Metropolitan Region, Thailand. METHODS AND RESULTS: Twenty-seven recycled water and twenty-three sewage sludge samples were tested for the presence of norovirus genogroup (G)I and GII using RT-nested PCR. Molecular characterization of noroviruses was undertaken by DNA sequencing and phylogenetic analysis. The level of the RNA genome of the noroviruses was determined using quantitative real-time RT-PCR. Noroviruses were detected in 44·4% of recycled water samples and 73·9% of sewage sludge samples. Norovirus GI.2 and GII.4 were identified in recycled water samples at levels of 2·19 × 101 and 3·26 × 104 RNA copies per litre. Six different genotypes of GI (GI.1, GI.2, GI.5a, GI.5b, GI.6b and GI.7) and GII.17 were identified in sewage sludge samples at levels ranging from 1·99 × 101 -1·43 × 105 RNA copies per gram wet weight. Four recombinant norovirus strains were detected in sewage sludge samples, namely GII.P16-GII.2, GII.P16-GII.4, GII.P16-GII.13 and GII.P21-GII.13. CONCLUSIONS: These findings provide evidence that noroviruses may be spread to the community and environment via the use of recycled water for plant areas, and sewage sludge for land application. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study demonstrating recombinant norovirus strains in sewage sludge samples. The presence of noroviruses in recycled water and sewage sludge contributes to a health risk of environmental exposure.

First Determination of the Level Structure of an sd-Shell Hypernucleus, _{Λ}

We report on the first observation of γ rays emitted from an sd-shell hypernucleus, _{Λ}^{19}F. The energy spacing between the ground state doublet, 1/2^{+} and 3/2^{+} states, of _{Λ}^{19}F is determined to be 315.5±0.4(stat)_{-0.5}^{+0.6}(syst) keV by measuring the γ-ray energy of the M1(3/2^{+}→1/2^{+}) transition. In addition, three γ-ray peaks are observed and assigned as E2(5/2^{+}→1/2^{+}), E1(1/2^{-}→1/2^{+}), and E1(1/2^{-}→3/2^{+}) transitions. The excitation energies of the 5/2^{+} and 1/2^{-} states are determined to be 895.2±0.3(stat)±0.5(syst) and 1265.6±1.2(stat)_{-0.5}^{+0.7}(syst) keV, respectively. It is found that the ground state doublet spacing is well described by theoretical models based on existing s- and p-shell hypernuclear data.

Significant augmentation of regulatory T cell numbers occurs during the early neonatal period.

Regulatory T cells (Tregs ) control immune responses by suppressing various inflammatory cells. Tregs in newborn babies may play an important role in preventing excessive immune responses during their environmental change. We examined the number and phenotype of Tregs during the neonatal period in 49 newborn babies. Tregs were characterized by flow cytometry using cord blood (CB) and peripheral blood (PB) from the early (7-8 days after birth) and late (2-4 weeks after birth) neonatal periods. CD4+ forkhead box protein 3 (FoxP3+ ) T cells were classified into resting Tregs (CD45RA+ FoxP3low ), activated Tregs (CD45RA- FoxP3high ) and newly activated T cells (CD45RA- FoxP3low ). Compared with CB and PB during the late neonatal period, the percentage of Tregs and all Treg subpopulations in the CD4+ lymphocyte population were increased significantly during the early neonatal period. Furthermore, the proportion and absolute number of activated Tregs were increased markedly compared with other Treg subpopulations, such as resting Tregs and newly activated T cells (non-Tregs ), in the early neonatal period. Increased Tregs concomitantly expressed the suppressive molecule cytotoxic T lymphocyte antigen-4 (CTLA-4). The up-regulated expression of chemokine receptor 4 (CCR4) and down-regulated expression of CCR7 were also observed in expanded Tregs . When cord blood cells were cultured in vitro with CD3 monoclonal antibodies (mAb) for 5 days, CD4+ CD45RA- FoxP3high cells were increased significantly during the culture. Thus, the presence of increased activated Tregs in early neonates may play an important role in immunological regulation by suppressing excessive T cell activation caused by the immediate exposure to ubiquitous antigens after birth.

Effects of rare sugar D-allulose on acid production and probiotic activities of dairy lactic acid bacteria.

It has recently been reported that the rare sugar d-allulose has beneficial effects, including the suppression of postprandial blood glucose elevation in humans, and can be substituted for sucrose as a low-calorie food ingredient. To examine the applications of d-allulose in the dairy industry, we investigated the effects of d-allulose on the acid production of 8 strains of yogurt starter (Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus) and 4 strains of lactococci, including potential probiotic candidates derived from dairy products. Acid production by 2 L. delbrueckii ssp. bulgaricus yogurt starter strains in milk was suppressed by d-allulose, but this phenomenon was also observed in some strains with another sugar (xylose), a sugar alcohol (sorbitol), or both. In contrast, among the dairy probiotic candidates, Lactococcus lactis H61, which has beneficial effects for human skin when drunk as part of fermented milk, was the only strain that showed suppression of acid production in the presence of d-allulose. Strain H61 did not metabolize d-allulose. We did not observe suppression of acid production by strain H61 with the addition of xylose or sorbitol, and xylose and sorbitol were not metabolized by strain H61. The acid production of strain H61 after culture in a constituted medium (tryptone-yeast extract-glucose broth) was also suppressed with the addition of d-allulose, but growth efficiency and sugar fermentation style were not altered. Probiotic activities-such as the angiotensin-converting enzyme inhibitory activity of H61-fermented milk and the superoxide dismutase activity of H61 cells grown in tryptone-yeast extract-glucose broth-were not affected by d-allulose. d-Allulose may suppress acid production in certain lactic acid bacteria without altering their probiotic activity. It may be useful for developing new probiotic dairy products from probiotic strains such as Lactococcus lactis H61.

Clinical and epidemiological characteristics of acute respiratory virus infections in Vietnamese children.

Information about viral acute respiratory infections (ARIs) is essential for prevention, diagnosis and treatment, but it is limited in tropical developing countries. This study described the clinical and epidemiological characteristics of ARIs in children hospitalized in Vietnam. Nasopharyngeal samples were collected from children with ARIs at Ho Chi Minh City Children's Hospital 2 between April 2010 and May 2011 in order to detect respiratory viruses by polymerase chain reaction. Viruses were found in 64% of 1082 patients, with 12% being co-infections. The leading detected viruses were human rhinovirus (HRV; 30%), respiratory syncytial virus (RSV; 23·8%), and human bocavirus (HBoV; 7·2%). HRV was detected all year round, while RSV epidemics occurred mainly in the rainy season. Influenza A (FluA) was found in both seasons. The other viruses were predominant in the dry season. HRV was identified in children of all age groups. RSV, parainfluenza virus (PIV) 1, PIV3 and HBoV, and FluA were detected predominantly in children aged 24 months, respectively. Significant associations were found between PIV1 with croup (P < 0·005) and RSV with bronchiolitis (P < 0·005). HBoV and HRV were associated with hypoxia (P < 0·05) and RSV with retraction (P < 0·05). HRV, RSV, and HBoV were detected most frequently and they may increase the severity of ARIs in children.

Human rhinovirus infections in hospitalized children: clinical, epidemiological and virological features.

Molecular epidemiology and clinical impact of human rhinovirus (HRV) are not well documented in tropical regions. This study compared the clinical characteristics of HRV to other common viral infections and investigated the molecular epidemiology of HRV in hospitalized children with acute respiratory infections (ARIs) in Vietnam. From April 2010 to May 2011, 1082 nasopharyngeal swabs were screened for respiratory viruses by PCR. VP4/VP2 sequences of HRV were further characterized. HRV was the most commonly detected virus (30%), in which 70% were diagnosed as either pneumonia or bronchiolitis. Children with single HRV infections presented with significantly higher rate of hypoxia than those infected with respiratory syncytial virus or parainfluenza virus (PIV)-3 (12·4% vs. 3·8% and 0%, respectively, P < 0·05), higher rate of chest retraction than PIV-1 (57·3% vs. 34·5%, P = 0·028), higher rate of wheezing than influenza A (63·2% vs. 42·3%, P = 0·038). HRV-C did not differ to HRV-A clinically. The genetic diversity and changes of types over time were observed and may explain the year-round circulation of HRV. One novel HRV-A type was discovered which circulated locally for several years. In conclusion, HRV showed high genetic diversity and was associated with significant morbidity and severe ARIs in hospitalized children.

Immune responses against norovirus GII.4 virus-like particles in mice.

Norovirus (NoV) is a causative agent of gastroenteritis in children and adults worldwide. To evaluate the safety and effectiveness of a NoV vaccine candidate, 100 µg of GII.4 NoV-like particles (VLPs) was challenged orally (oral and intrabuccal administration) and by subcutaneous injection without adjuvant in mice. The subcutaneous injection induced IgG in sera, but not IgA in feces. The oral delivery method induced IgA in both sera and feces, but not IgG in sera. However, challenging by the intrabuccal administration induced IgG in sera and IgA in both sera and feces, especially by 2-dose immunization. The peak of specific immune responses by the intrabuccal administration was detected later than that of the oral delivery method. Heterologous immune responses against other genotypes were also recognized. NoV-specific IFN-γ was detected after the intrabuccal administration. These findings indicated that the administration of NoV VLPs by intrabuccal administration could induce the best immune responses against NoV in mice.

Observation of Spin-Dependent Charge Symmetry Breaking in ΛN Interaction: Gamma-Ray Spectroscopy of _{Λ}

The energy spacing between the spin-doublet bound state of _{Λ}^{4}He(1^{+},0^{+}) was determined to be 1406±2±2 keV, by measuring γ rays for the 1^{+}→0^{+} transition with a high efficiency germanium detector array in coincidence with the ^{4}He(K^{-},π^{-})_{Λ}^{4}He reaction at J-PARC. In comparison to the corresponding energy spacing in the mirror hypernucleus _{Λ}^{4}H, the present result clearly indicates the existence of charge symmetry breaking (CSB) in ΛN interaction. By combining the energy spacings with the known ground-state binding energies, it is also found that the CSB effect is large in the 0^{+} ground state but is vanishingly small in the 1^{+} excited state, demonstrating that the ΛN CSB interaction has spin dependence.

Evaluation of immunochromatography tests for detection of novel GII.17 norovirus in stool samples.

A novel GII.17 norovirus has emerged as a major cause of epidemic and endemic acute gastroenteritis in several countries in Asia. We used a small panel of stool samples in which GII.17 virus had been quantified by real-time RT-PCR to evaluate four commercially available norovirus immunochromatography (IC) kits. At least 10(8) copies/mL of GII.17 virus were required by each IC kit for a positive result, which is 1,000-fold more than that reported for these assays for GII.4 viruses.

Prevalence, seasonality, and peak age of infection of enteric adenoviruses in Japan, 1995-2009.

A total of 7185 faecal specimens collected from infants and children with gastroenteritis in seven different regions of Japan during 1995-2009 were examined for adenovirus by polymerase chain reaction. Adenovirus was detected in 568 (7.9%) patients. The adenovirus activity peak was in winter and spring seasons (December-March) during the study period in the Japanese paediatric population. During the last 15 years, adenovirus 41 was the most predominant strain in Japan.

Aluminium-free glass polyalkenoate cements: ion release and in vitro antibacterial efficacy.

Glass polyalkenoate cements (GPCs) have exhibited potential as bone cements. This study investigates the effect of substituting TiO2 for SiO2 in the glass phase and the subsequent effect on cement rheology, mechanical properties, ion release and antibacterial properties. Glass characterization revealed a reduction in glass transition temperature (T(g)) from 685 to 669 °C with the addition of 6 mol % TiO2 (AT-2). Magic angle spinning nuclear magnetic resonance (MAS-NMR) revealed a shift from -81 ppm to -76 pmm when comparing a Control glass to AT-2, indicating de-polymerization of the Si network. The incorporation of TiO2 also increased the working time (T(w)) from 19 to 61 s and setting time (T(s)) from 70 to 427 s. The maximum compressive strength (σ(c)) increased from 64 to 85 MPa. Ion release studies determined that the addition of Ti to the glass reduced the release of zinc, calcium and strontium ions, with low concentrations of titanium being released. Antibacterial testing in E. coli resulted in greater bactericidal effects when tested in aqueous broth for both titanium containing cements.

Structure determination in a new type of amorphous molecular solids with different nonlinear optical properties: a comparative structural analysis.

The microscopic structures of two amorphous molecular solids with extremely nonlinear optical properties have been studied. They consist of organotetrel chalcogenide clusters with the chemical formula [(RSn)4S6]. The basic molecular building blocks are adamantane-like {Sn4S6} cores with organic ligands R attached to the Sn atoms. While the material equipped with R=naphthyl generates frequency doubling upon irradiation with a simple infrared laser diode, the material decorated with R=phenyl responds by emitting brilliant white light. The structural differences were investigated using x-ray scattering and extended x-ray absorption fine structure combined with molecular Reverse Monte Carlo. Transmission electron microscopy and scanning precession electron diffraction were used to examine structural differences from mesoscopic down to microscopic scales. Characteristic differences were found on all scales. While close core-to-core distances between {Sn4S6} cluster cores and molecular distortions are found in the white light emitting material, undistorted molecules and significantly larger core distances characterize the material showing frequency doubling. Here however, results of scanning precession electron diffraction reveal the formation of nanocrystalline structures in the amorphous matrix, which we identify as cause for the suppression of white light emission.

Supercooling and vitrification of aqueous glycerol solutions at normal and high pressures.

The supercooling and vitrification of aqueous glycerol solutions was studied at high pressures. Homogeneous ice nucleation temperatures (T(H)) were obtained for aqueous glycerol solutions of R=50, 30, 20, 12, and 10 (R: moles of water/moles of glycerol) up to 300MPa. The R=20 glycerol solution formed a glass above 200MPa at a cooling rate of 200°C/min, indicating that pressure enhances glass-formation of aqueous glycerol solutions. The (dT(g)/dP) values were obtained for vitrified aqueous glycerol solutions of R=3, 5, 10, and 20. These data can be used for the development of cryo-preservation liquids for living cells at high pressures.