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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.

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.

This study examined the temporal variations in radiocesium concentration associated with sinking particles in the northeastern Japan Sea between September 2010 and July 2012. We analyzed sediment trap samples from this period after the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident in March 2011. Cesium-134 was detected in samples collected between May and July 2011 at a depth of 1100 m (4.2–11 mBq g-dry−1) but not in other periods at 1100 m or deeper (3100 and 3500 m). These results confirmed the deposition of FDNPP-derived radiocesium on the surface water in the late April 2011, which rapidly sank with sinking particles to a depth of at least 1100 m, in the northeastern Japan Sea, about 40 days after the deposition in the North Pacific. If FDNPP-derived 137Cs was excluded, no seasonal changes were detected in the 137Cs activity concentration of the sinking particles, and the 137Cs activity concentration of the particles increased with increasing depth. Judging from the concentration of 137Cs of sinking particle and seasonal variation of total mass flux and organic matter content, the lithogenic particle seems to be important for radiocesium associated with sinking particles. These data also strongly suggest a difference in sinking features of particles between 2010–2011 and 2011–2012 deployments. Due to the existence of benthic front, shallow water (1100 m) and deep water (3500 m) are separated during 2010–2011 deployment, but in the winter of 2011–2012, this front disappeared and the particles in surface water seem to have sunk to the depth of 3100 m. The sinking velocity of the particles at 1100 m was estimated to be 33–62 m day−1, with a mean sinking velocity of 43 m day−1. These values were comparable to those estimated at depths shallower than 1000 m in the North Pacific after the FDNPP accident, or in the Mediterranean, North, and Black Seas after the Chernobyl accident.

We investigated lateral profiles of 228Ra (half-life; 5.75 years) activity and 228Ra/226Ra (1600 years) activity ratio using 241 surface water samples collected in/around the Sea of Japan and the East China Sea (ECS) during June–October of 2009–2014. In the ECS, the 228Ra/226Ra ratio in the surface waters exhibited markedly wide variation (

A new DC muon beamline MuSIC was set up at the Research Centre for Nuclear Physics (RCNP), Osaka University. The MuSIC beamline provides an intense low-energy muon beam with distinc- tive devices of superconducting solenoid magnets. A beamline commissioning and a feasibility study for $\mu$SR (Muon spin rotation, relaxation and resonance) are in progress. In the commissioning, ∼10$^5$ count/(sec·1$\mu$A-proton) of negative muons and ∼10$^6$ count/(sec·1$\mu$A-proton) of positive muons were measured with TOF setup in the experimental port using 60 MeV/$c$ muon beam. The non-destructive elemental analyses and nuclear physics experiments with a negative muon beam have been recently started. In a feasibility study for μSR with a positive muon beam, we observed spin asymmetry spectra with a test sample in a magnetic field of 0.004 Tesla using a newly constructed $\mu$SR spectrometer.

A double-$\Lambda$ hypernucleus, ${}_{\Lambda\Lambda}\mathrm{Be}$, was observed by the J-PARC E07 collaboration in nuclear emulsions tagged by the $(K^{-},K^{+})$ reaction. This event was interpreted as a production and decay of $ {}_{\Lambda\Lambda}^{\;10}\mathrm{Be}$, ${}_{\Lambda\Lambda}^{\;11}\mathrm{Be}$, or ${}_{\Lambda\Lambda}^{\;12}\mathrm{Be}^{*}$ via $\Xi^{-}$ capture in ${}^{16}\mathrm{O}$. By assuming the capture in the atomic 3D state, the binding energy of two $\Lambda$ hyperons$\,$($B_{\Lambda\Lambda}$) of these double-$\Lambda$ hypernuclei are obtained to be $15.05 \pm 0.11\,\mathrm{MeV}$, $19.07 \pm 0.11\,\mathrm{MeV}$, and $13.68 \pm 0.11\,\mathrm{MeV}$, respectively. Based on the kinematic fitting, ${}_{\Lambda\Lambda}^{\;11}\mathrm{Be}$ is the most likely explanation for the observed event., Comment: 11 pages, 3 figures

We analyzed a total of 25 seawater samples collected from 2 columns within the Sea of Japan for 226Ra (half life 1,600 years) and 228Ra (half life 5.75 years) by employing low-background γ-spectrometry. The 228Ra activity level in the deep proper water (DPW) (~0.13 mBq/L) was found to be higher than that of deep waters from the Pacific and Atlantic Oceans (

To assess the migration patterns of radiocesium emitted from the Fukushima Dai-ichi Nuclear Power Plant (FDNPP), we analyzed (228)Ra/(226)Ra ratios and (7)Be concentrations and compared them with (134)Cs and (137)Cs concentrations in seawater samples collected within the Sea of Japan before and after the FDNPP accident (i.e., during the period 2007-2012) using low-background γ-spectrometry. The (228)Ra/(226)Ra ratios in surface waters exhibited lateral and seasonal variations, reflecting the flow patterns of surface water. This indicates the transport patterns of the FDNPP-derived radiocesium by surface water. Cosmogenic (7)Be (half-life: 53.3 d) exhibited markedly high concentrations (5-10 mBq/L) at depths shallower than 50 m, with concentrations decreasing steeply (0.2-2 mBq/L) at depths of 50-250 m. The distribution of (7)Be concentrations suggests that the downward delivery of the FDNPP-derived radiocesium to below 50 m depth was negligible for a few months prior to its removal from the Sea of Japan.

We collected 14 water column seawater samples in the southwestern Okhotsk Sea and 7 surface samples around the northern area of Hokkaido Island, Northern Japan, and employed low-background γ-spectrometry with convenient minimal radiochemical processing to determine the activities of (226)Ra (half-life t(1/2)=1600 y), (228)Ra (5.75 y), (137)Cs (30.2 y), and (228)Th (1.91 y) in the samples. Activities of (226)Ra (~2.3 mBq/L), (228)Ra (~0.7 mBq/L), and (137)Cs (~1 mBq/L) of surface waters on the Okhotsk Sea side show notable differences from those on the Japan Sea side (Soya Warm Current Water; SWCW) (~1.5 mBq/L; 1.5-2 mBq/L; 1.4-1.6 mBq/L), indicating their different origins and lateral mixing patterns. All of these nuclides exhibit unique vertical profiles; activities of soluble (226)Ra, (228)Ra, (137)Cs, and reactive (228)Th exhibit small variations from 50 to 500 m depth ((226)Ra, ~2.2 mBq/L; (228)Ra, ~0.4 mBq/L; (137)Cs, ~1 mBq/L; (228)Th, ~0.13 mBq/L). These profiles can be explained by the convective mixing of surface water such as the East Sakhalin Current Water (ESCW) to this layer.

Copyright © 2012 by The Geochemical Society of Japan. and mixing. While the 134Cs and 137Cs concentrations of highly contaminated surface seawater samples around the FDNPP have been studied extensively (Tsumune et al., 2012; Honda et al., 2012), relatively little information is available on radionuclide concentrations in seawater for other sea areas around the Japanese Archipelago. We previously reported low levels of 134Cs and 137Cs concentrations in surface water samples from the Pacific Ocean side of northeastern Japan, the Japan Sea, and the southwestern Okhotsk Sea before and after the FDNPP accident; however, the scope of these studies was somewhat cursory (Inoue et al., 2012a, b). Nonetheless, these studies illustrated the need for more extensive temporal and spatial investigations to assess the oceanic behaviors and fate of Fukushima-derived radionuclides around the Japanese Islands. We therefore used low-background γ-spectrometry to characterize the lateral variations of 134Cs and 137Cs concentrations in surface waters around the Japanese Archipelago in June and October 2011. These data were combined with 134Cs deposition data (Ministry of Education, Low levels of 134Cs and 137Cs in surface seawaters around the Japanese Archipelago after the Fukushima Dai-ichi Nuclear Power Plant accident in 2011

We present measurements of nu_mu disappearance in K2K, the KEK to Kamioka long-baseline neutrino oscillation experiment. One hundred and twelve beam-originated neutrino events are observed in the fiducial volume of Super-Kamiokande with an expectation of 158.1^{+9.2}_{-8.6} events without oscillation. A distortion of the energy spectrum is also seen in 58 single-ring muon-like events with reconstructed energies. The probability that the observations are explained by the expectation for no neutrino oscillation is 0.0015% (4.3sigma). In a two flavor oscillation scenario, the allowed Delta m^2 region at sin^2(2theta) is between 1.9 and 3.5 x 10^{-3} eV^2 at the 90% C.L. with a best-fit value of 2.8 x 10^{-3} eV^2., Comment: 40 pages, 48 figures

A new 3-axis magnetic field measurement system based on the Hall elements has been constructed at KEK. The new system was designed for the larger magnets of higher energy accelerator facilities such as J-PARC. We employed a 7 m long 2 m wide iron base, and the magnet and the field mapping machine were set on the same base. We set pivot fittings at intervals of 250 mm through the longer side of the base. Therefore the alignment accuracy between the mapping machine and the magnet is promised within 0.1 mm in total by simply putting the magnet on the base. In addition, by teaching the mapping-machine coordinates of the two separate points on the magnet axis to the mapping machine, the field measurement points on the magnet coordinates can automatically be calculated and positioned in software way. We used three single-axis Hall elements mass-produced by industry. 3 Hall elements could be mounted on a rectangular PEEK block. The distance between hall elements is approximately 3.3 mm. The accuracy of 3 directions of Hall elements is within 0.5 degrees. The temperature of Hall elements was controlled within 60 /spl plusmn/0.1 degrees centigrade. Owing to the light weight of the Hall sensor unit and the strong carbon fiber rod with one side support, the bend of the rod was less than 10 mm for 2200 mm rod length. Thus we have successfully measured the field of the big Q-magnet, whose bore diameter and length are 200 mm and 3 m.

To assess the delivery mechanism of radiocesium emitted from the Fukushima Dai-ichi Nuclear Power Plant (FDNPP), we examined vertical profiles of (134)Cs, (137)Cs, and (228)Ra concentrations and the (228)Ra/(226)Ra ratio in the water columns off the Sanriku Coast in the northwestern Pacific Ocean, in July 2012, along with their surface lateral variations in July 2009. Radiocesium concentrations exhibited maximum peaks (3-5 mBq/L for (134)Cs) at depths of 100-200 m, accompanied by high (228)Ra concentrations (0.6-0.8 mBq/L) in comparison with shallower depths (∼0.4 mBq/L). Taking the circulation patterns of currents in the area into account, it was inferred that radioactive depositions were supplied to the (228)Ra-rich Tsugaru Warm Current Water (TWCW) in the offshore area of the Sanriku Coast following the FDNPP accident, and that after the spring of 2011, this water (∼26.5σθ) was covered by lower density surface water, which helped intrude its way to depths of 100-200 m.

A 17-year-old man with severe cardiac failure due to dilated cardiomyopathy was treated by medication. As he did not improve, he had indication for transplantation of the heart and was put on a ventricular assist system as a bridge until he could be transplanted. He also had severe tricuspid regurgitation and tricuspid annuloplasty was performed. Inhalation of nitric oxide was used to decrease pulmonary vascular resistance. Although cerebral infarction was present postoperatively, he is waiting for transplant without paralysis. The ventricular assist system proved to be useful therapy for serious cardiac failure due to terminal dilated cardiomyopathy.

A 14-day-old, 2,042 g neonate with interrupted aortic arch (IAA) type B was admitted to our hospital because of respiratory failure. Although alprostadil and alprostadil alfadex were used to keep the ductus arteriosus open, her congestive heart failure became worse and anuria and metabolic acidosis started to appear. We performed single-stage repair for her at 14 days old. Continuous hemodiafiltration (CHDF) was initiated immediately after the operation and peritoneal dialysis was started after paralytic ileus improved. CHDF improved her renal function and she was discharged at postoperative day 84. We conclude that CHDF is effective for neonates with acute renal failure although circulation management is rather difficult.

A 1-month-old girl weighting 3.1 kg was diagnosed as tetralogy of Fallot (TOF) with pulmonary artery atresia (PA) and aberrant right subclavian artery. Before the operation, pulmonary blood flow from a ducus arteriosus was maintained by lipo prostaglandin E1 (PGE1). The patient underwent palliative right ventricular outflow tract reconstruction (pRVOTR) because the proximal aberrant right subclavian artery was stenotic and the ductus arteriosus and branch of the left pulmonary artery were so close. Postoperative course was uneventful and pulmonary artery showed good growth. The pRVOTR as 1st procedure is a useful method for hypoplastic pulmonary artery to get equal and good growth. Although there are controversies about the size of right ventricular outflow tract (RVOT), 5 or 6 mm diameter of RVOT is recommended for the operative repair of hypoplastic left heart syndrome. We concluded that the pRVOTR should be one of the options as 1st palliative procedure for TOF with PA and diminutive pulmonary artery.

We report a rare case of acquired left ventricular-right atrial communication resulting from infective endocarditis. A 57-year-old male with aortic regurgitation due to infective endocarditis was referred to our hospital because of severe congestive heart failure. Preoperative transthoracic echocardiography showed aortic, mitral and tricuspid severe regurgitations. Intraoperative transesophageal echocardiography revealed left ventricular-right atrial shunt. The fistula was located at the atrioventricular membranous septum. The communication site from the left view was below the commissure between the right coronary cusp and non-coronary cusp, and from the right view was just above the tricuspid annulus of the septal leaflet. The fistula was closed directly with mattress suture and aortic valve replacement and both mitral and tricuspid ring annuloplasty were carried out simultaneously. The postoperative course was uneventful. It is important to inspect shunts carefully in echocardiography of infective endocarditis with massive regurgitations.

Acute aortic obstruction induced by acute aortic dissection frequently causes life-threatening organ ischemia. Although early reperfusion of lower extremities, renal and mesenteric artery is necessary, surgical treatment such as graft replacement is invasive and may result in myonephropathic-metabolic syndrome (MNMS), which leads to loss of limb and life. We herein report a case of stent placement as a less invasive treatment for true lumen obliteration associated with Stanford type B aortic dissection in a patient with chronic renal failure on hemodialysis. Ten mm metallic stents were placed in the obliterated true lumen of the descending aorta in order to perfuse peripheral organs within 5 hours after occurrence. It relieved symptoms of visceral organ and leg ischemia. On the postoperative day 14, abdominal discomfort after meal, hypertension in the upper extremity and headache appeared. Chest and abdominal computed tomography (CT) revealed stenosis of the true lumen proximal to the stents. On the other hand, the diameter of the true lumen was inversely dilated distal to the stents. Bilateral axillo-femoral artery bypass was performed with relief of upper extremity hypertension and visceral organ ischemia. The patient otherwise had an uneventful course and was discharged on the postoperative day 37. Our experience suggests that emergency stent placement can provide an option that is less invasive, more effective and prompt treatment for patients with visceral organ and leg ischemia resulting from acute aortic dissection.

Hyperthyroidism is known to affect multiple organ functions, and thyroid hormone has been known to improve myocardial function in a failing heart. The purpose of this study is to elucidate the functional and metabolic effects of thyroid hormone on myocardium in a rat model exposed to long-term excess thyroid hormone, particularly focusing on the SR Ca(2+)-ATPase (SERCA2) function. 3,5,3'-Triiodo-L-thyronine (T3), or the vehicle, was subcutaneously given for 4 weeks (T3 and control [C] group). Bolus I.V. Thapsigargin (TG) was used to test the SERCA2 function (C-TG and T3-TG) in Langendorff perfused heart. Myocardial functions such as LV-developed pressure (LVDP; mmHg), +/- dP/dt (mmHg/s), tau (ms), and oxygen consumption (MVO(2); ml/min/g wt) were measured. SERCA2 and GLUT4 protein level were also evaluated by Western immunoblotting. Left ventricle to body weight (LV/BW) ratio was significantly higher in the T3 group. Both negative dP/dt and tau were significantly decreased by TG. It is interesting that the decrement of negative dP/dt and tau attained by TG was significantly larger in the hyperthyroid group (T3-TG) than in a normal heart (C-TG). SERCA2 and GLUT4 protein levels were not significantly different between control and the T3 group. We conclude that prolonged exposure to thyroid hormone causes hypertrophy of the myocardium and an augmentation of the SR Ca(2+) ATPase activity. Care must be taken in hyperthyroid heart during the ischemia-reperfusion process where the SRECA2 function is inhibited.

In off-pump coronary artery bypass grafting (off-pump CABG: OPCAB) procedures involving multiple vessels, the Aorta No-Touch technique is increasingly being adopted to avoid cerebral infarction, while gastro-epiploic artery (GEA)-left anterior descending coronary artery branch (LAD) anastomosis or composite T-grafting is performed to supply blood to multiple coronary arteries through the left internal thoracic artery (LITA) as an inflow conduit. The objective of the present study is to investigate the effectiveness and advisability of grafting in patients who undergo OPCAB involving multiple vessels, including those who undergo standard CABG. CONCLUSIONS 1: Composite T-grafts of the LITA in OPCAB involving multiple vessels can present certain problems with patency, patient survival, and need for subsequent revision procedures. In the event of a graft failure, serious symptoms resembling left main coronary trunk (LMT) may develop. 2: The incidence of cardiac events with GEA-LAD is high, and patency in the distal phase is poor. 3: Ideally, LITA-LAD should be performed alone. 4: Among patients who have been screened before the procedure, satisfactory results are obtained for OPCAB in which the ascending aorta serves as an inflow conduit; this procedure should be considered as a viable option.

From October 1996 until August 2000, coronary artery bypass grafting (CABG) for right coronary artery was performed via diaphragmatic approach. This procedure was done in 18 patients consist of 13 male and 5 female ranging in age from 47 to 81 years old. Ten of 18 cases were performed coronary bypass reoperation. Right gastroepiploic artery was used in 16 cases, and branched radial artery or saphenous vein graft from gastroduodenal artery was used in one case. Bypassed region in right coronary artery was segment 3 in 9 cases, right posterior descending artery in 8 and right atrio-ventricular branch in one. All grafts were patent in postoperative cardiac catheterization. This approach was desirable for the case, which bypass grafting to right coronary artery is necessary, on account of avoiding injury of patent bypassed graft by median sternotomy in re-do CABG. For the patient whose stomach had been resected, bypass grafting from gastroduodenal artery with radial artery or saphenous vein graft to right coronary artery is useful procedure.

Preoperative evaluation of the both right ventricular (RV) systolic and diastolic function using the pulsed Doppler echocardiogram were examined for 46 patients scheduled for the pulmonary resection of the pulmonary tumorous lesions. The parameters which included the RV inflow pattern at the tricuspid orifice and the RV ejection flow pattern at the RV outflow tract were obtained by the pulsed Doppler echocardiogram. Following results were obtained. 1) The RV afterload shown by the parameters of the acceleration time (AT, time beginning of RV ejection to peak velocity) were higher in the aged patients, the low FEV 1% populations, and the patients having the deteriorated left ventricular contraction. 2) The RV diastolic dysfunction were present preoperatively in aged patients over the 60 years old. This phenomenon was characterized by a high degree of atrial contraction and an increased ratio of the peak velocity in atrial contraction phase to that in early rapid filling phase (A/E). When we evaluate the RV inflow and ejection Doppler flow patterns after the major lung resection, these findings must be considerable thing.

A 65-years-old woman admitted to the hospital in order to treat of the mediastinal tumor, but she suffered from palpitation, slight fever, sweating, uneasiness, sleeplessness and weightloss. On the physical examination, she was experiencing tachycardia, fevering (37.2 approximately 37.6 degrees C). Skin was moist but had no exophtalmos or neck tumor. Chest X-ray showed an abnormal shadow in the upper mediastinum. On chest CT, a tumor mass (9 x 5 x 4 cm) with cystic regions and scattered calcifications occupied from anterior to posterior mediastinum. The tumor compressed trachea to the left and right brachiocephalic vein and SVC to the right. Lower portion of the tumor intruded into behind of the trachea. Lymph node swelling of mediastinum was also detected. Results of general laboratory examination were within normal limits. Thyroid function test revealed hyperthyroidism; T3U 58%, free T3 24.4 pg/ml, free T4 6.0 ng/dl and thyroglobulin 967 mg/dl, but TSH was0.01 microIU/ml. After daily administration of methimazole (300 mg/day) for 4 weeks, thyroid function became to normal level and symptoms of hyperthyroidism was disappeared. The tumor was completely extirpated with right hemithyroidectomy and lymph node dissection under neck colla incision and median sternotomy. Pathological finding of the tumor showed follicular-fetal adenoma of thyroid with hyaloid degeneration and cystic change. There was no finding suspected of Graves' disease. She is well without any complications for 8 months after operation. Some discussion of the literature was mentioned.

A total of 30 surface water samples were collected at 2 sites on the east side of the East China Sea (ECS) during 2008-2010, and 226 Ra, 228 Ra, and 228 Th activities were measured using low-background γ-spectrometry. The 228 Ra/ 226 Ra and 228 Th/ 228 Ra activity ratios of the samples exhibited notable seasonal variations ( 228 Ra/ 226 Ra = 0.2-3.3; 228 Th/ 228 Ra = < 0.1-0.4) accompanying salinity changes (31.0-34.6). These changes are hypothesized to cause the change by altering the mixing ratio of 228 Ra-rich and particle-rich continental shelf water within the ECS.