Discovery of

The new isotope ^{39}Na, the most neutron-rich sodium nucleus observed so far, was discovered at the RIKEN Nishina Center Radioactive Isotope Beam Factory using the projectile fragmentation of an intense ^{48}Ca beam at 345 MeV/nucleon on a beryllium target. Projectile fragments were separated and identified in flight with the large-acceptance two-stage separator BigRIPS. Nine ^{39}Na events have been unambiguously observed in this work and clearly establish the particle stability of ^{39}Na. Furthermore, the lack of observation of ^{35,36}Ne isotopes in this experiment significantly improves the overall confidence that ^{34}Ne is the neutron dripline nucleus of neon. These results provide new key information to understand nuclear binding and nuclear structure under extremely neutron-rich conditions. The newly established stability of ^{39}Na has a significant impact on nuclear models and theories predicting the neutron dripline and also provides a key to understanding the nuclear shell property of ^{39}Na at the neutron number N=28, which is normally a magic number.

Swelling of Doubly Magic

Interaction cross sections for ^{42-51}Ca on a carbon target at 280 MeV/nucleon have been measured for the first time. The neutron number dependence of derived root-mean-square matter radii shows a significant increase beyond the neutron magic number N=28. Furthermore, this enhancement of matter radii is much larger than that of the previously measured charge radii, indicating a novel growth in neutron skin thickness. A simple examination based on the Fermi-type distribution, and mean field calculations point out that this anomalous enhancement of the nuclear size beyond N=28 results from an enlargement of the core by a sudden increase in the surface diffuseness of the neutron density distribution, which implies the swelling of the bare ^{48}Ca core in Ca isotopes beyond N=28.

How Different is the Core of

The structure of a neutron-rich ^{25}F nucleus is investigated by a quasifree (p,2p) knockout reaction at 270A MeV in inverse kinematics. The sum of spectroscopic factors of π0d_{5/2} orbital is found to be 1.0±0.3. However, the spectroscopic factor with residual ^{24}O nucleus being in the ground state is found to be only 0.36±0.13, while those in the excited state is 0.65±0.25. The result shows that the ^{24}O core of ^{25}F nucleus significantly differs from a free ^{24}O nucleus, and the core consists of ∼35% ^{24}O_{g.s.}. and ∼65% excited ^{24}O. The result may infer that the addition of the 0d_{5/2} proton considerably changes neutron structure in ^{25}F from that in ^{24}O, which could be a possible mechanism responsible for the oxygen dripline anomaly.

Location of the Neutron Dripline at Fluorine and Neon.

A search for the heaviest isotopes of fluorine, neon, and sodium was conducted by fragmentation of an intense ^{48}Ca beam at 345 MeV/nucleon with a 20-mm-thick beryllium target and identification of isotopes in the large-acceptance separator BigRIPS at the RIKEN Radioactive Isotope Beam Factory. No events were observed for ^{32,33}F, ^{35,36}Ne, and ^{38}Na and only one event for ^{39}Na after extensive running. Comparison with predicted yields excludes the existence of bound states of these unobserved isotopes with high confidence levels. The present work indicates that ^{31}F and ^{34}Ne are the heaviest bound isotopes of fluorine and neon, respectively. The neutron dripline has thus been experimentally confirmed up to neon for the first time since ^{24}O was confirmed to be the dripline nucleus nearly 20 years ago. These data provide new keys to understanding the nuclear stability at extremely neutron-rich conditions.

Discovery of

The discovery of the important neutron-rich nucleus _{20}^{60}Ca_{40} and seven others near the limits of nuclear stability is reported from the fragmentation of a 345 MeV/u ^{70}Zn projectile beam on ^{9}Be targets at the radioactive ion-beam factory of the RIKEN Nishina Center. The produced fragments were analyzed and unambiguously identified using the BigRIPS two-stage in-flight separator. The eight new neutron-rich nuclei discovered, ^{47}P, ^{49}S, ^{52}Cl, ^{54}Ar, ^{57}K, ^{59,60}Ca, and ^{62}Sc, are the most neutron-rich isotopes of the respective elements. In addition, one event consistent with ^{59}K was registered. The results are compared with the drip lines predicted by a variety of mass models and it is found that the models in best agreement with the observed limits of existence in the explored region tend to predict the even-mass Ca isotopes to be bound out to at least ^{70}Ca.

Spectroscopy of Pionic Atoms in

We observed the atomic 1s and 2p states of π^{-} bound to ^{121}Sn nuclei as distinct peak structures in the missing mass spectra of the ^{122}Sn(d,^{3}He) nuclear reaction. A very intense deuteron beam and a spectrometer with a large angular acceptance let us achieve a potential of discovery, which includes the capability of determining the angle-dependent cross sections with high statistics. The 2p state in a Sn nucleus was observed for the first time. The binding energies and widths of the pionic states are determined and found to be consistent with previous experimental results of other Sn isotopes. The spectrum is measured at finite reaction angles for the first time. The formation cross sections at the reaction angles between 0° and 2° are determined. The observed reaction-angle dependence of each state is reproduced by theoretical calculations. However, the quantitative comparison with our high-precision data reveals a significant discrepancy between the measured and calculated formation cross sections of the pionic 1s state.

Evaluation of microbial diversity in the pilot-scale beer brewing process by culture-dependent and culture-independent method.

AIMS: In the brewing industry, microbial management is very important for stabilizing the quality of the product. We investigated the detailed microbial community of beer during fermentation and maturation, to manage beer microbiology in more detail. METHODS AND RESULTS: We brewed a beer (all-malt) and two beerlike beverages (half- and low-malt) in pilot-scale fermentation and investigated the microbial community of them using a next-generation sequencer (454 GS FLX titanium), quantitative PCR, flow cytometry and a culture-dependent method. From 28 to 88 genera of bacteria and from 9 to 38 genera of eukaryotic micro-organisms were detected in each sample. Almost all micro-organisms died out during the boiling process. However, bacteria belonging to the genera Acidovorax, Bacillus, Brevundimonas, Caulobacter, Chryseobacterium, Methylobacterium, Paenibacillus, Polaromonas, Pseudomonas, Ralstonia, Sphingomonas, Stenotrophomonas, Tepidimonas and Tissierella were detected at the early and middle stage of fermentation, even though their cell densities were low (below approx. 10(3) cells ml(-1) ) and they were not almost detected at the end of fermentation. CONCLUSIONS: We revealed that the microbial community of beer during fermentation and maturation is very diverse and several bacteria possibly survive during fermentation. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, we revealed the detailed microbial communities of beer using next-generation sequencing. Some of the micro-organisms detected in this study were found in beer brewing process for the first time. Additionally, the possibility of growth of several bacteria at the early and middle stage of fermentation was suggested.

Halo structure of the island of inversion nucleus 31Ne.

The cross sections for single-neutron removal from the very neutron-rich nucleus 31Ne on Pb and C targets have been measured at 230 MeV/nucleon using the RIBF facility at RIKEN. The deduced large Coulomb breakup cross section of 540(70) mb is indicative of a soft E1 excitation. Comparison with direct-breakup model calculations suggests that the valence neutron of 31Ne occupies a low-l orbital (most probably 2p(3/2)) with a small separation energy (S(n) approximately < 0.8 MeV), instead of being predominantly in the 1f(7/2) orbital as expected from the conventional shell ordering. These findings suggest that 31Ne is the heaviest halo system known.

Is driving a car a risk for Legionnaires' disease?

Legionnaires' disease (LD) is a major cause of severe community-acquired pneumonia but the source and mode of transmission are not always apparent, especially in sporadic cases. We hypothesized that LD can be acquired from the air-conditioning systems of motor cars. Swabs were taken from the evaporator compartments of the air-conditioning system of scrapped cars. Healthy subjects who were mainly employees of regional transportation companies were tested for antibody to Legionella pneumophila serogroups 1-6; they also completed a questionnaire. Legionella species were detected in 11/22 scrapped cars by the loop-mediated isothermal amplification method. The prevalence of microplate agglutination titres > or =1:32 was significantly higher in subjects who sometimes used car air-conditioning systems. Although we did not prove a direct link between Legionella spp. in the car evaporator and LD, our findings point to a potential risk of car air-conditioning systems in LD, which needs further investigation.

Emission- and fluorescence-spectroscopic investigation of a glow discharge plasma: absolute number density of radiative and nonradiative atoms in the negative glow.

The excited-state atom densities in the negative glow of a direct-current glow discharge are derived from the spectral-line intensity of radiative atoms and the resonance-fluorescence photon flux of nonradiative atoms. The discharge is operated in a helium-argon gas mixture (molar fraction ratio 91:9; total gas pressure 5 Torr) at a dc current of 0.7-1.2 mA. The observations are made in the region of the maximum luminance in the cathode region, where high-energy electrons accelerated in the cathode fall are injected into the negative glow. The emission intensities of the He I, He II, Ar I, and Ar II spectral lines are measured with a calibrated tungsten ribbon lamp as an absolute spectral-radiance standard. Fluorescence photons scattered by helium and argon atoms in the metastable state and argon atoms in the resonance state are detected by the laser-induced fluorescence (LIF) method with the Rayleigh scattering of nitrogen molecules as an absolute standard of scattering cross section. The laser absorption method is incorporated to confirm the result of the LIF measurement. Excitation energies of the measured spectral lines range from 11.6 (Ar I) to 75.6 eV (He II), where the excitation energy is measured from the ground state of the neutral atom on the assumption that, in the plasma of this study, both the neutral and the ionic lines are excited by electron impact in a single-step process from the ground state of the corresponding neutral atoms. Experimental evidence is shown for the validity of this assumption.

Traditional Chinese medicine and Kampo: a review from the distant past for the future.

Traditional Chinese medicine (TCM) is a complete system of healing that developed in China about 3000 years ago, and includes herbal medicine, acupuncture, moxibustion and massage, etc. In recent decades the use of TCM has become more popular in China and throughout the world. Traditional Japanese medicine has been used for 1500 years and includes Kampo-yaku (herbal medicine), acupuncture and acupressure. Kampo is now widely practised in Japan and is fully integrated into the modern health-care system. Kampo is based on TCM but has been adapted to Japanese culture. In this paper we review the history and characteristics of TCM and traditional Japanese medicine, i.e. the selection of traditional Chinese herbal medicine treatments based on differential diagnosis, and treatment formulations specific for the 'Sho' (the patient's symptoms at a given moment) of Japanese Kampo--and look at the prospects for these forms of medicine.

Angiotensin-II receptor antagonist alleviates non-alcoholic fatty liver in KKAy obese mice with type 2 diabetes.

We examined the effects of the angiotensin-II receptor antagonist candesartan on non-alcoholic fatty liver (NAFL) and circulating adiponectin concentrations in KKAy obese mice with type 2 diabetes mellitus. The KKAy mice were randomly assigned to receive either candesartan at a once-daily dose of 10 mg/kg (n = 5) or placebo (n = 5). The differences in liver weight, histological evaluation of hepatic lipid infiltration, serum adiponectin concentration and hepatic adiponectin mRNA levels between the two groups were determined on day 7 after treatment was initiated. Candesartan-treated mice demonstrated significantly lower liver weights and reduced lipid droplets in hepatic cells compared with control mice. The circulating adiponectin levels and hepatic expression of adiponectin mRNA were significantly higher in candesartan-treated mice than control mice. These results suggest that candesartan might alleviate NAFL through elevation of circulating adiponectin levels in KKAy obese mice with type 2 diabetes mellitus.

Advanced oesophageal carcinoma in an 84-year-old treated with chemoradiotherapy.

We present a case of advanced oesophageal cancer with cardiac invasion in an 84-year-old male presenting with dysphagia and general malaise. Histological analysis of an endoscopic biopsy specimen revealed a poorly differentiated squamous cell carcinoma. Computed tomography indicated a thickened oesophageal wall that was compressing the left atrium, suggesting invasion of the heart, and oesophagography revealed a polypoid lesion 9 cm in length. No distant metastases were seen on computed tomography. The patient was given chemotherapy with 10 mg/m2 cisplatin on days 1 and 4 every week for 5 weeks and concurrent radiotherapy at a dose of 2 Gy five times per week (total dose 52 Gy). After 4 weeks, the mass was no longer visible on oesophagography or endoscopic examination. The patient was free of recurrence and metastases for 4.5 years. In conclusion, chemoradiotherapy may be curative in elderly patients with unresectable oesophageal carcinoma.

The presence of myoglobin in human thyroid tissue.

In the present study we sought to determine the presence of myoglobin in human thyroid tissue. When reacted with antihuman myoglobin antibody on the Ouchterlony plate, homogenates of human thyroid tissue formed a precipitation line. When the human thyroid extract was included in human myoglobin RIA, the dilution curve of thyroid extract was parallel to the standard curve of myoglobin. When the myoglobin immunoreactivity in thyroid extract was fractionated with Sephadex G 75 column, the immunoreactivity was eluted in a peak identical with authentic myoglobin. The position of the peak was different from that of thyroglobulin. Myoglobin concentration in thyroid tissue was estimated to be 0.7-110 mg/g wet wt, being about 1/6000 to 1/40 of that in skeletal muscle. Histochemical studies demonstrated the presence of myoglobin immunoreactivity in thyroid tissue, especially in the apical border of thyroid epithelial cells, implying a functional role in iodinating process or exocytotic-endocytotic process.

Portal venoplasty for recipients in living-related liver transplantation.

BACKGROUND: In living-related liver transplantation (LRLT) in small children, standard end-to-end portal vein (PV) anastomosis is usually difficult because of a inadequate total PV length, or because of a size mismatch between the graft and the recipient PV. In this report, we present our new portal venoplasty technique for the recipient PV. METHODS: After dissection of the recipient PV, the wall between the right and left branches of the PV is severed longitudinally as in the branch patch technique. The anterior and posterior edges of both branches are joined using running sutures, to form a longer and wider PV for anastomosis. RESULTS: This new portal venoplasty technique was used in 7 of 28 child cases, and gave good results without thrombosis or other complications. CONCLUSIONS: Our new portal venoplasty technique is useful in LRLT in small children when the recipient or graft PV is not long enough.

Risk factors for hyperamylasemia after hepatectomy using the Pringle maneuver: randomized analysis of surgical parameters.

OBJECTIVES: To determine whether the increased portal venous pressure caused by use of the Pringle maneuver contributes to inducing posthepatectomy hyperamylasemia and, subsequently, to evaluate risk factors for its development. DESIGN: Randomized study. SETTING: University hospital. PATIENTS: Forty patients who were going to undergo hepatectomy were assigned prospectively to either a superior mesenteric artery clamp (n=20) or a nonclamp (n=20) group by the random-block method. INTERVENTIONS: The Pringle maneuver was used during hepatectomy, and in the superior mesenteric artery clamp group the superior mesenteric arteries were clamped simultaneously. MAIN OUTCOME MEASURES: Amylase activity, isozyme, and creatinine levels in the blood and urine samples were measured before and after surgery, and the amylase creatinine clearance ratio was estimated. RESULTS: The serum amylase activity levels of the superior mesenteric artery clamp and nonclamp groups did not differ significantly during the 7 postoperative days. The serum amylase activity levels exceeded 250 U/L in 14 patients (group 1) and remained below this level in 26 (group 2). The salivary-type isozyme levels of group 1 increased significantly compared with those of group 2, and the levels of group 2 remained normal. The total amount of amylase excreted in the urine samples of group 1 patients also increased significantly, with the salivary-type isozyme predominating. All the mean amylase creatinine clearance ratios before and after surgery remained normal. The mode chi2 of the logistic model including the indocyanine green retention rate at 15 minutes and the ratio of the resected liver weight to the whole liver volume showed a significantly increased risk (P=.01). CONCLUSION: It is not the increased portal venous pressure caused by use of the Pringle maneuver but the liver function and the extent of liver resection that are considered risk factors for inducing posthepatectomy salivary-type hyperamylasemia.

Objective evaluation of liver consistency to estimate hepatic fibrosis and functional reserve for hepatectomy.

BACKGROUND: The empiric evaluation of liver consistency is currently used to plan the surgical strategy. The aim of this study was to verify the feasibility of the objective measurement of liver consistency and to check its correlation with liver fibrosis and liver functional reserve. STUDY DESIGN: Fifty-two consecutive patients who underwent hepatic resections in our department were enrolled. The indications for liver resection were hepatocellular carcinoma in 36 patients, metastatic liver tumors in 12 patients, and other conditions in 4 patients. Liver consistency was measured with a new tactile sensor. A fibrosis index was calculated as an expression of the percentage of fibrotic tissue. Liver consistency was compared with the degree of liver fibrosis observed in histologic specimens (fibrosis index) and with liver function parameters. RESULTS: Liver stiffness showed a significant positive correlation with fibrosis index (r = 0.887, p < 0.0001). Liver stiffness also showed significant positive correlation with the indocyanine green test (r = 0.631, p < 0.0001) by a univariate analysis. The indocyanine green test and platelet count were independently and significantly associated with liver stiffness by a multiple regression analysis. In five patients, the liver stiffness values measured intraoperatively differed markedly from those expected from the indocyanine green test values. In these patients, the operative procedures were finally selected based on the liver stiffness measured with the tactile sensor and good clinical outcomes were obtained. CONCLUSIONS: These results show for the first time that liver stiffness can be clinically assessed quantitatively by means of the tactile sensor. The tactile sensor adequately estimates liver stiffness and this estimation is well correlated with liver fibrosis and functional reserve. Liver consistency determined objectively in this manner may be useful for optimizing surgical decision making.

Reduction of delayed neuronal death by inhibition of protein synthesis.

Brief forebrain ischemia in rodents causes delayed neuronal death selectively in the CA1 pyramidal cells of hippocampus. Treatment with a reversible protein synthesis inhibitor, anisomycin, significantly reduced the occurrence of delayed neuronal death in the Mongolian gerbil. This result indicates that de novo synthesis of certain protein(s), collectively termed 'killer protein' is required, possibly due to deprivation of nerve growth factor or other trophic factors.

Histological changes of muscle in a patient with pyruvate dehydrogenase deficiency.

Histological changes of muscle from a 17-month-old boy with pyruvate dehydrogenase deficiency are presented. The patient had muscle hypotonia, mental retardation, seizures, lactic acidosis and hyperalaninemia. Deficient activity of the pyruvate dehydrogenase complex was found in his platelets (about 25% of normal) and of pyruvate dehydrogenase in his biopsied muscle (about 5% of normal). A muscle biopsy specimen showed an increased proportion of type IIC fibers (24%), fiber-type grouping and lipid droplet accumulation.