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The patient was a 42-year-old female who had advanced rectal cancer(Ra, type 2)with liver metastasis. The preoperative diagnosis was T2N1H2, but the liver tumor was unresectable for hepatic vein invasion in September, 2004. She underwent low anterior resection for primary rectal cancer at first after she was given S-1 80 mg/day(14 days)for a histological effect judgment. The pathological diagnosis was moderately-differentiated adenocarcinoma, ss, n1, and the histological effect was Grade 1a. Because CT showed reduction of liver metastasis after the operation, she was treated with 2 courses of chemotherapy using S-1. Radiographic examination showed reduction of liver metastasis(36%)and improvement of hepatic vein invasion. In January, 2005, she underwent hepatectomy and the pathological diagnosis was moderately-differentiated adenocarcinoma, metastasis and the histological effect was Grade 1a. There has not been any recurrence for 48 months after hepatectomy. We experienced this case in which preoperative S-1 proved effective for liver metastasis from rectal cancer.

The reconstruction of massive bone and joint defect after resection of malignant tumor, severe traumatic loss, osteomylitis or congenital deformity, has used artificial materials. But this procedure has severe problems such as those of endurance, infection, non-union, pathological fracture and joint instability. So the reconstruction procedure made use of biomaterials and many attempts had been tried before. Recently the concept of the vascularized allogeneic joint transplantation was introduced to solve these complications, but the clinial application has not been reported yet and is still in the experimental stages.We used a genetically inbred rat which was suitable for immunological investigetion and made a model knee joint orthotopical transplantation across a genetically incompatible pair. We particularly paid attention to the vascularity of the grafted joint and investigated its reaction to immunosuppression with cyclosporine in the short and long term.As the result, after withdrawal of immunosuppression the graft was rapidly rejected and in many cases pathological fractures occurred around the knee joint, losing its skeletal support and joint function.On the other hand, under continuous immunosuppression the graft was proved to be living without any degenrative changes and its joint function remained.

The purpose of this paper is to discribe follow-up study for cervical spondylotic amyotrophy. Twenty-one patients were followed up and studied. There were 19 males and 2 females. The mean age of patients was 54 years with a range from 17 to 67 yeats. The duration of follow-up varied from 2 years to 12 years, the average being 6 years and 2 months.At the time of follow-up, disturbance of the shoulder joint was absent in 8 patients, improved in 10 patients and unchanged in 3 patients. Muscle atrophy was absent in 7 patients, improved in 5 patients and unchanged in 9 patients. Generally speaking, improvement of motor disturbance of the shoulder is inferior to that of muscle atrophy.Factors of improvement of muscle atrophy are as follows:1) Less than 1 year in duration of symptoms.2) Large diameter of cervical canal.3) Acute onset such as cervical disc herniation.Clinical course showed two kinds of pathogenesis. One is root involvement type and another is anterior horn involvement type. This disease almost has good clinical course but anterior horn involvement type is more or less difficult to recover muscle atrophy compared with root invovement type. Two types have each some characteristics respectively but it is difficult to expect the prognosis of this clinical entity before the treatment.

In a recent LSI, IR drop on power supply lines is a significant problem for high speed operation, along with an increase of power consumption. In addition, relaxing external stresses during assembly processes is also a serious issue, because more fragile low-k materials are applied to interlayer dielectric films. In this paper, we have developed new structures without adding global interconnect layers. Against the IR drop issue, we have developed 2 different structures. The first structure is the new mesh wiring structure and we have successfully reduced IR drop by 20%. The second structure is the electroless plated shunt line structure and we have successfully obtained reduction in resistance of power supply lines by 38%. To the issue of relaxing stresses, we have succeeded in reducing an assembly stress to 7% with electroless plating. These results indicate that superior structure of global layers can be realized without an increase in chip cost.

We present our NMR studies of double-layer hydrated cobalt oxides NaxCoO2-yH2O (x ~ 0.35, y ~ 1.3) with various Tc = 0 - 4.8 K and magnetic transition temperatures. High-resolution $^{1}$H NMR spectrum served as an evidence for the existence of H$_{3}$O$^{+}$ oxonium ions. $^{23}$Na nuclear spin-lattice relaxation rates served to detect local field fluctuations sensitive to Tc. $^{59}$Co nuclear quadrupole resonance (NQR) spectra served to classify the various Tc samples. From the classification by $^{59}$Co NQR frequency, the double-layer hydrated compounds were found to have two superconducting phases closely located to a magnetic phase. In the normal state and at a magnetic field in the $ab$-plane, two $^{59}$Co NMR signals with different Knight shifts and different $^{59}$Co nuclear spin-lattice relaxation times $^{59}T_{1}$ were observed. The two $^{59}$Co NMR signals suggest magnetic disproportionation of two Co sites or in-plane (XY) anisotropy of a single Co site. Non Korringa behavior and power law behavior in zero-field NQR 1/$^{59}T_{1}$ above and below Tc suggest non-Fermi liquid and unconventional superconductivity.

We report a novel critical exponent delta=3/2 of magnetization curves M=H^{1/delta} near the ferromagnetic quantum phase transitions of Sr1-xAxRuO3 (A = Ca, La0.5Na0.5, and La), which the mean field theory of the Ginzburg-Landau-Wilson type fails to reproduce. The effect of dirty ferromagnetic spin fluctuations might be a key., Comment: 4 pages, 5 figures

We report 7Li NMR studies of V-substitution effects on spinel oxide superconductor LiTi2O4 (Tc = 13.4 K). In LiTi2-xVxO4 (x = 0-0.4), the V substitution for the Ti site suppressed the relative volume fraction of superconductivity faster than Tc. From the observation of fairly homogeneous enhancement in a 7Li nuclear spin-lattice relaxation rate, we conclude that the V substitution changes electron correlation effects through electron carrier doping from quarter electron filling 3d0.5 to 3d1.5 and then the antiferromagnetic correlation emerges., Comment: 4 pages, 7 figures

We report 7Li NMR studies of single crystals of triangular-lattice Heisenberg antiferromagnet Li7RuO6. Slow critical divergence with a wide critical region of |T/TN - 1|< 7 was observed in 7Li nuclear spin-lattice relaxation rate. The slowing down of staggered spin fluctuations was analyzed in a renormalized classical region of a two-dimensional triangular-lattice non-linear sigma model. A spin stiffness constant was found to reduce to about 20 % from the value in a spin-wave approximation. The effect of spin frustration, e.g., Z2 vortex excitations on the critical phenomena is suggested., 4 pages, 5 figures, the references were updated, to be published in J. Phys. Soc. Jpn. 78 (2009) No.2

59Co NQR studies of low frequency spin fluctuations of double‐layer hydrated triangular‐lattice superconductors and nonsuperconductors NaxCoO2−yH2O are presented. For all the samples, 59Co nuclear spin‐lattice relaxation rates 1/59T1 indicated non‐Korringa behaviors in the normal states. For the nonsuperconductor, 1/59T1 indicated a magnetic critical slowing down effect. The triangular‐lattice superconductivity emerges near a magnetic instability.

We have measured the transverse relaxation of the planar Cu(2) nuclear spins in an oriented powder sample of YBa 2 Cu 3 O 6.98 ( T c =92 K) by using the nuclear quadrupole resonance (NQR) technique. Above T c , after subtraction of the T 1 process, the spin echo envelope decay follows a Gaussian form, and its time constant is almost independent of temperature. In the vicinity of T c , however, the Gaussian line shape is gradually narrowed. The calculated value ( T G =149 µsec) for the Gaussian time constant based on the direct nuclear dipole-dipole interaction is comparable to the experimental one ( T G =131±2 µsec) at 297 K. Hence, the nuclear indirect coupling proposed previously may not be needed. Below T c , the Gaussian line shape was found to be narrowed depending on H 1 , and especially, it is sharply narrowed at 35 K and 87 K.

The 63 Cu nuclear quadrupole resonance (NQR) technique has been utilized to investigate the dynamical properties of CuO in paramagnetic states. The NQR frequency increases linearly with increasing temperature. The spin-lattice relaxation rate 1/ T 1 asymptotically approaches a constant value 1/ T 1∞ of 1.16±0.02×10 3 sec -1 at high temperatures. Below about 350 K, the rate begins to increase, and near the Neel temperature of 229∼230 K, it diverges due to the critical slowing down. The critical region is found to be not very wide (( T - T N )/T_N\lesssim0.5). A n e s t i m a t e d v a l u e f o r 1/T_1∞ i n t e r m s o f e x c h a n g e c o u p l e d l o c a l m o m e n t s i s i n g o o d a g r e e m e n t w i t h t h e e x p e r i m e n t a l v a l u e . F r o m t h e v i e w p o i n t o f t h e s p i n - l a t t i c e r e l a x a t i o n e x p e r i m e n t s , C u O a p p e a r s t o b e a w e l l - l o c a l i z e d m a g n e t i c i n s u l a t o r .

Membrane resistance across poly(vinyl chloride)entrapping spirobenzopyran was reversibly controlled by UV and visible light irradiation. After UV light irradiation, the magnitude of the membrane resistance became less than 1/1000.

The purpose of this paper is to describe two things. One is to describe comparison of the structure of the subarachnoid angle in human and monkey spinal nerve roots. The other is to discuss the function of the subarachnoid angle.Eight monkeys weighing 7-10kg were used. our of them were untreated and experimental nerve root infiltration was performed for the others. Then they were evaluated macroscopically and histologically.The main results found in this study were as follows:1) The structure of the connective tissue of the spinal nerve roots in the area of the subarachnoid angle were essentially same in the human and monkeys.2) Arachnoid villi were found near the subarachnoid angle.3) We suggest that the subarachnoid angle has a function as a pathway which connects the subarachnoid space and epidural space.

Background To establish the criteria for selecting a mitral annuloplasty ring of the correct size, the dimensions of the mitral valve orifice were analyzed in cadaveric hearts. Materials and results From December 2000 to July 2006, the mitral valve diameter [DM (Obs)] and Z-values [DM (Z); standardized value based on Rowlatt's criteria], the angles of the trigones (theta Tg) and commissures (theta Com) and the intertrigonal distance [L (T)] were measured in 82 fresh cadaveric hearts from cases with variable causes of death (mean age 64.8+/-15.7 years; body surface area [BSA] 1.51+/-0.21 m2). DM (Obs), DM (Z) and L (T) were 2.8+/-0.5 cm, 1.16+/-0.98, and 1.8+/-0.2 cm, respectively. Theta Tg and theta Com averaged 76+/-13 and 121+/-11 degrees, respectively. There was a significant inverse linear relationship between DM (Z) and theta Tg [theta Tg =-10x DM (Z) +88] and a significant logarithmic correlation between L (T) and BSA [L (T) =0.54xLn (BSA) +1.55]. The anterior annular length and L (T) remained unchanged. Conclusion In non-dilated cadaveric hearts, the trigones were located at one-quarter of the mitral annulus, so the appropriate length of the posterior annuloplasty band should be adjusted to L (T) x3.33.

We report $^{125}\mathrm{Te}$ NMR studies for single crystals of $\mathrm{Ce}{\mathrm{Te}}_{3}$ between 10 and $307\phantom{\rule{0.3em}{0ex}}\mathrm{K}$, under an applied field of $H=7.4847\phantom{\rule{0.3em}{0ex}}\mathrm{T}$ along the $a$ or $b$ axis $H\ensuremath{\Vert}ab$ and the $c$ axis $H\ensuremath{\Vert}c$, respectively. We observed that the $^{125}\mathrm{Te}$ NMR spectra consist of a superposition of broad and sharp peaks, which we assign to the signals of $^{125}\mathrm{Te}(1)$ in double Te(1) sheets and $^{125}\mathrm{Te}(2)$ in CeTe(2) bilayers, respectively. For $H\ensuremath{\Vert}ab$, a broad $^{125}\mathrm{Te}(1)$ NMR spectrum shows a powder pattern with three split lines, which is evidence for an incommensurate charge-density wave modulation. The $^{125}\mathrm{Te}(1)$ NMR spectrum with three lines broadens with cooling. Knight shifts widely distributed from $\ensuremath{-}0.16%$ to $+0.58%$ at $110\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ indicate that a spin density of conduction electron is polarized from Ce local moments. For $H\ensuremath{\Vert}c$, a spectrum has a fine structure with three lines, and the linewidth of the $^{125}\mathrm{Te}(1)$ NMR spectrum is narrow compared with that for $H\ensuremath{\Vert}ab$. On the other hand, the anisotropic Knight shift of the $^{125}\mathrm{Te}(2)$, which is located at the CeTe(2) bilayer, is positive with proportion to the anisotropic bulk susceptibility for $H\ensuremath{\Vert}ab$ and $H\ensuremath{\Vert}c$. The hyperfine coupling constants of $^{125}\mathrm{Te}(2)$ are nearly isotropic but the nuclear spin-lattice relaxation rate is strongly anisotropic, indicating the anisotropic spin fluctuations in this system. The nuclear spin-lattice relaxation rate of the $^{125}\mathrm{Te}(2)$ diverges due to the slowing down of spin fluctuations.

We report on pulsed 1H NMR studies of the hydroxyl OH groups in magnesium hydroxide Mg(OH)2 at 77–355 K at 42.5772 MHz. The Fourier-transformed NMR spectra show the superposition of broad and narrow components. The broad NMR spectrum is assigned to dipole-coupled protons on a rigid lattice in the bulk Mg(OH)2, while the narrow NMR spectrum is assigned to extrinsic protons, e.g., conduction protons facilitated by lattice defects. We found a monotonically decreasing linewidth of the broad NMR spectrum on heating. The monotonic decrease in the linewidth is associated with hopping protons around a threefold axis (rotational hydroxyl protons).

Search for dark energy potentials in quintessence Yusuke Muromachi1, Akira Okabayashi2, Daiki Okada3, Tetsuya Hara3,∗, and Yutaka Itoh3,∗ 1Altec Corporation, Queen’s Tower C 18F, Yokohama, 220-6218, Japan 2Graduate School of Human and Environmental Studies, Kyoto University, Kyoto 608-8501, Japan 3Department of Physics, Kyoto Sangyo University, Kyoto 603-8555, Japan ∗E-mail: hara@cc.kyoto-su.ac.jp, yitoh@cc.kyoto-su.ac.jp

We found a nearly \(\sqrt {T}\) dependence of the planar 63 Cu nuclear spin-lattice relaxation rate 1/ T 1 for the 63 Cu-enriched overdoped La 2- x Sr x CuO 4 ( x =0.23; T c ∼20 K), using the 63 Cu NMR spin-echo technique. Considering both the transport and the magnetic properties, we conclude that the overdoped compound with x =0.23 is a three-dimensional nearly antiferromagnetic metal. The results indicate that a crossover in the antiferromagnetic spin fluctuation spectrum from two to three dimensions occurs as the Sr content increases beyond x ∼0.20. This is consistent with the dimensional crossover in conduction suggested from the results of electrical resistivity measurements.

We observed the pseudo spin-gap behavior in the T -dependences of 63 Cu Knight shift and NMR relaxation rates, as well as electrical resistivity, over a wide doping range for the bilayer high- T c HgBa 2 CaCu 2 O 6+δ using 63 Cu NMR spin-echo technique. We found a difference in the doping dependence of the pseudo spin-gap behavior between HgBa 2 CaCu 2 O 6+δ and the previous monolayer HgBa 2 CuO 4+δ . The results indicate that the pseudo spin-gap behavior strongly depends on the underlying electronic states.

Percutaneous vertebroplasty has become an option for the treatment of painful osteoporotic compression fractures in patients in whom conservative medical management has failed.This paper assessed the effectiveness and safety of percutaneous vertebroplasty in patients with focal pain caused by compression vertebral body fractures.Over a twenty-five-month period 63 patients underwent percutaneous vertebroplasty, and ten of these patients were subsequently retreated, for a total of 73 operations on 93 vertebrae. The patients were affected by osteoporotic compression fractures (n=57) or by benign or malignant infiltrative processes (n=6). All patients were examined at discharge and thereafter to assess the level of pain and investigate possible changes in the quality of life. The mean length of follow-up was 15.2 months.After treatment, almost 90% of patients reported complete disappearance or significant alleviation of the pain. In 7 of 63 of the patient (11%) there were small asymptomatic leakages of cement outside the vertebral body. A substantial number of patients with osteoporosis, 19% of the study population, experienced new fractures following treatment with vertebroplasty.Our experience confirms the effectiveness of vertebroplasty to pain caused by vertebral fractures. If the indications are strictly followed, improvement of symptoms is often immediate, allowing the return of mobility, and patient satisfaction with surgery is higher. The use of appropriate systems limits the number of complications.

We report the magnetic properties of Sr- and Bi-substituted samples of the one-dimensional alternating $S=1∕2$ spin chain compound ${\mathrm{Pb}}_{2}{\mathrm{V}}_{3}{\mathrm{O}}_{9}$. In the Sr-substituted system, we obtained two series of samples synthesized by different heat treatments; one series shows the reduction of the spin gap without antiferromagnetic long-range order (AF-LRO) and the other shows AF-LRO at low temperatures. We also observed impurity-induced AF-LRO in the Bi-substituted system. The fitting results of magnetic susceptibilities imply the possible coexistence of a spin gap and AF-LRO in both AF-LRO systems. These observations of AF-LRO with a small amount of substitution indicate that the magnetic instability involving a quantum critical point is inherent in the spin-gap system ${\mathrm{Pb}}_{2}{\mathrm{V}}_{3}{\mathrm{O}}_{9}$.

We report 23Na NMR studies of the polycrystalline samples of double-layer hydrated cobalt oxides NaxCoO2.yH2O (x ~ 0.35 and y ~ 1.3) with the superconducting transition temperatures Tc < 1.8K and ~4.5K, and the dehydrated NaxCoO2 (x ~ 0.35). The hyperfine field and the electric field gradient at the Na sites in the non-hydrated Na0.7CoO2 and the dehydrated Na0.35CoO2 are found to be significantly reduced by the hydration, which indicates a strong shielding effect of the intercalated water molecules on the Na sites. The temperature dependence of 23 Na nuclear spin-lattice relaxation rate 1/23T1 of the non-superconducting double-layer hydrate NaxCoO2.yH2O is found to be similar to that of the non-hydrated Na0.7CoO2, whose spin dynamics is understood by A-type (intra-layer ferromagnetic and inter-layer antiferromagnetic) spin fluctuations. The superconducting phase is located close to the quantum critical point with the A-type magnetic instability., 4 pages, 4 figures

We present an experimental magnetic phase diagram based on two spin-gaps (a dynamical spin gap Δ R estimated from nuclear spin-lattice relaxation rate 1/ T 1 and a static one Δ S estimated from static uniform spin susceptibility χ s ) for low-dimensional quantum spin systems: one-dimensional (1D) Haldane gap, two-leg spin ladder, dimer spin, 2D plaquette spin, and high- T c Cu oxide systems. Possible universal correlation for respective materials and their mutual relations are discussed.

We succeeded in synthesizing the powder samples of bilayer-hydrate sodium cobalt oxide superconductors NaxCoO2-yH2O with Tc = 0 ~ 4.6 K by systematically changing the keeping duration in a 75 % relative humidity atmosphere after intercalation of water molecules. From the magnetic measurements, we found that the one-day duration sample does not show any superconductivity down to 1.8 K, and that the samples kept for 2 ~ 7 days show superconductivity, in which Tc increases up to 4.6 K with increasing the duration. Tc and the superconducting volume fraction are almost invariant between 7 days and 1month duration. The 59Co NQR spectra indicate a systematic change in the local charge distribution on the CoO2 plane with change in duration., 4 pages, 5 figures, submitted to Journal of the Physical Society of Japan

We evaluate the clinical significance of portal venous expandable metallic stent (EMS) placement for patients who have malignant portal hypertension caused by recurrent periampullary cancer.Four post-pancreatoduodenectomy patients underwent percutaneous transhepatic portal venous EMS placement because of symptoms of malignant portal hypertension: intractable ascites (2/4), growth of abnormal collateral vein (3/4), melena (2/4), gastroesophageal varix (3/4) and thrombocytopenia (2/4). They were diagnosed with having a recurrence by cytology of ascitis, computed tomography and/or tumor markers in serum. The stenosis segment was measured by percutaneous-transhepatic portography and was dilated with a balloon prestent placement. The patency of stent was confirmed using Doppler ultrasonography and enhanced computed tomography at least once a month.The portal venous pressure was significantly decreased from (24.5 +/- 3.92 mmH2O) to (19.5 +/- 3.87 mmH2O) and the symptoms related to portal hypertension were reduced in all patients. There were no complications related to EMS placement. All patients were alive more than a year later and two of four patients were alive more than two years without morbidity.Percutaneous-transhepatic portal EMS placement is a minimally invasive procedure and is a useful treatment against malignant portal hypertension caused by recurrent periampullary cancer.

The Co Knight shift was measured in an aligned powder sample of Na_xCoO_2yH_2O, which shows superconductivity at T_c \sim 4.6 K. The Knight-shift components parallel (K_c) and perpendicular to the c-axis (along the ab plane K_{ab}) were measured in both the normal and superconducting (SC) states. The temperature dependences of K_{ab} and K_c are scaled with the bulk susceptibility, which shows that the microscopic susceptibility deduced from the Knight shift is related to Co-3d spins. In the SC state, the Knight shift shows an anisotropic temperature dependence: K_{ab} decreases below 5 K, whereas K_c does not decrease within experimental accuracy. This result raises the possibility that spin-triplet superconductivity with the spin component of the pairs directed along the c-axis is realized in Na_xCoO_2yH_2O., Comment: 5 pages, 5 figures, to be published in Journal of Physical Society of Japan vol. 75, No. 1

We observed the pseudo spin-gap behavior of spin excitations in lightly doped single- CuO 2 -layer HgBa 2 CuO 4+δ ( T c =50, 72 and 80 K) using the Cu NMR spin-echo technique. The results indicate that lightly doped high- T c Cu oxide inherently possesses the pseudo spin-gap.

Recent experimental results of Cu nuclear spin-spin and spin-lattice relaxation rates are analyzed to clarify the nature of quantum ground states of the high- T c Cu oxides. From comparisons with the current theories, it is found that (i) the RPA-type quasi-particle picture works fairly well in describing the doping-dependence of the actual ground states, (ii) the nesting degree of the Fermi surface is higher for lower doping, and (iii) the strong nesting near half-filling may play a key role in the composition variation.

We analyzed nonexponential ${}^{63}\mathrm{Cu}$ nuclear spin-lattice relaxation curves for ${}^{63}\mathrm{Cu}$-enriched high-${T}_{c}$ superconductors: ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{CuO}}_{4}$ with $x=0.13$ (slightly underdoped) and 0.18 (slightly overdoped), and studied the applicability of an impurity-induced nuclear spin-lattice relaxation theory. We found a remnant of pseudo-spin-gap effect on the host ${}^{63}\mathrm{Cu}$ nuclear spin-lattice relaxation time and slow inhomogeneous spin fluctuation via the impurity-induced relaxation time. The effect of slow spin dynamics was also observed in ${}^{139}\mathrm{La}$ nuclear spin-lattice relaxation. The inhomogeneous electron-spin fluctuation, which is associated with randomly distributed staggered moments on the ${\mathrm{CuO}}_{2}$ plane, smears the pseudo-spin-gap. The fact that the optimal ${T}_{c}\ensuremath{\sim}38\mathrm{K}$ is smaller than ${T}_{c}\ensuremath{\sim}96\mathrm{K}$ of ${\mathrm{HgBa}}_{2}{\mathrm{CuO}}_{4+\ensuremath{\delta}}$ can be attributed to the depairing effect due to the slow spin fluctuation.

The time evolution of SANS functions of physical gelation of syndiotactic polystyrene (SPS) dispersed in chloroform was investigated by time-resolved SANS. The total scattering intensity Q increased with time in parallel with ordering of the TTGG-type skeletal conformation as revealed by time-resolved FT-IR. At early stages of gelation, the SANS functions were reproduced well by the theoretical equation derived for semidilute star polymers, and then converted to the form characteristic of continuous fractal objects. The structural parameters describing gel-network structures were evaluated as a function of gelation time and analyzed in connection with the sol—gel transformation mechanism.

Pancreas fistula is a well-known and severe complication of pancreaticoduodenectomy. It is difficult to control with conservative therapy, inducing further complications and severe morbidity. Until now, re-operation has been the only way to resolve pancreatic fistula causing complete dehiscence of the pancreatic-enteric anastomosis (complete pancreatic fistula). Percutaneous transgastric fistula drainage is one of the treatments for pancreatic fistula. This procedure allows both pancreas juice drainage and anastomosis re-construction at the same time. This is effective and minimally invasive but difficult to adapt to a long or complicated fistula. In particular, dilatation of the main pancreatic duct is indispensable. This paper reports the successful resolution of a postoperative pancreatic fistula by a two-way-approach percutaneous transgastric fistula drainage procedure. Using a snare catheter from the fistula and a flexible guidewire from the transgastric puncture needle, it can be performed either with or without main pancreatic duct dilatation.

We studied local electronic states near Zn in optimally doped ${\mathrm{YBa}}_{2}({\mathrm{Cu}}_{1\ensuremath{-}x}{\mathrm{Zn}}_{x}{)}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$ and underdoped ${\mathrm{YBa}}_{2}({\mathrm{Cu}}_{1\ensuremath{-}x}{\mathrm{Zn}}_{x}{)}_{4}{\mathrm{O}}_{8}$ via satellite signals of plane-site Cu(2) nuclear quadrupole resonance (NQR) spectra. From the relative intensity of Cu NQR spectra, the satellite signals are assigned to Zn-neighbor Cu NQR lines. The Cu nuclear spin-lattice relaxation time of the satellite signal is shorter than that of the main signal, which indicates that the magnetic correlation is locally enhanced near Zn both for the underdoped and the optimally doped systems. The pure ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{4}{\mathrm{O}}_{8}$ is a stoichiometric, homogenous, underdoped electronic system; nevertheless, the Zn-induced inhomogeneous magnetic response in the ${\mathrm{CuO}}_{2}$ plane is more marked than that of the optimally doped ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}.$

We studied Zn-substitution effect on the high-T_c superconductors, underdoped La_{2-x}Sr_xCu_{1-y}Zn_yO_4 (x=0.10; y=0, 0.01, 0.02), optimally doped (x=0.15; y=0, 0.02), and overdoped (x=0.20; y=0, 0.03, 0.06) in a temperature range of T=4.2-300 K, using Cu nuclear quadrupole resonance (NQR) spin-echo technique. We found full disappearance of the Cu NQR signals for the Zn-substituted, Sr-underdoped x=0.10 samples below about 40 K, partial disappearance for the Sr-optimally doped ones below about 50 K, but not for the overdoped x=0.20 ones. From the Zn-doping, the Sr-doping and the temperature dependence of the wipeout effect, we associate the wipeout effect with Zn-induced Curie magnetism or its extended glassy charge-spin stripe formation., Comment: 7 pages, 8 figures, to be published in J. Phys. Soc. Jpn. Vol.72, No. 7 (2003)

We report 59Co NMR studies on the magnetically oriented powder samples of Co-oxide superconductors NaxCoO2yH2O with Tc ~ 4.7 K. From two-dimensional powder pattern in the NMR spectrum, the ab-plane Knight shift in the normal state was estimated by the magnetic field dependence of second-order quadrupole shifts at various temperatures. Below 50 K, the Knight shift shows a Curie-Weiss-like temperature dependence, similarly to the bulk magnetic susceptibility chi. From the analysis of so-called K-chi plot, the spin and the orbital components of K and the positive hyperfine coupling constant were estimated. The onset temperature of superconducting transition in the Knight shift does not change so much in an applied magnetic field up to 7 T, which is consistent with the reported high upper critical field Hc2. The Knight shift at 7 T shows an invariant behavior below Tc. No coherence peak just below Tc was observed in the temperature dependence of the nuclear spin-lattice relaxation rate 1/T1 in both cases of NMR and NQR. We conclude that the invariant behavior of the Knight shift below Tc and unconventional behaviors of 1/T possibly indicate the spin-triplet superconductivity with p- or f-wave symmetry., Comment: 17 pages, 10 figures. Extended version

The effects of nonmagnetic Zn and magnetic Ni substitution for Cu site on magnetism are studied by measurements of uniform magnetic susceptibility for lightly doped La_{2-x}Sr_xCu_{1-z}M_zO_4 (M=Zn or Ni) polycrystalline samples. For the parent x=0, Zn doping suppresses the N\'{e}el temperature T_N whereas Ni doping hardly changes T_N up to z=0.3. For the lightly doped samples with T_N~0, the Ni doping recovers T_N. For the superconducting samples, the Ni doping induces the superconductivity-to-antiferromagnetic transition (or crossover). All the heavily Ni doped samples indicate a spin glass behavior at \~15 K., Comment: 2 pages including 3 figures, to be published in Physica C (LT23, Hiroshima 2002)

From the temperature dependence of the nuclear spin-lattice relaxation rate, 1/T1T, in the planar Cu(2) sites, it is found that a highly enhanced and strongly temperature-dependent relaxation process due to antiferromagnetic Cu spin fluctuations exists in all high-Tc superconducting oxides. The data also exhibit the opening of a gap in the low-lying magnetic excitations with an energy comparable to the superconducting gap. In contrast to this T1 behavior, the temperature variations of the indirectly coupled nuclear spin-spin relaxation rate, 1/T2g, and the anisotropic Knight shifts Kα have quite an independent signature; the former shows continuous increase toward Tc and the latter in the low low-doping regime decreases from a much higher temperature than that at which the spin-gap is seen in 1/T1T. These features indicate that the generalized spin susceptibility, χ(q,ω), has very characteristic temperature variations for different q and ω regions.

We have developed the local-field-enhancement model of the tail component of DRAM (dynamic random access memory) retention-time distribution. The model is in excellent agreement with experiments and proposes to control not the number but the energy-level distribution of traps and to reduce the space-charge-region-field variation together with the field itself to increase the retention time.

We report a systematic study of Zn-substitution effect on Cu NQR spectrum for high $T_c$ superconductors La$_{2-x}$Sr$_x$Cu$_{1-y}$Zn$_y$O$_4$ from carrier-underdoped to -overdoped regimes (polycrystalline samples, $x$ =0.10, 0.15, and 0.20). We observed no appreciable wipeout effect for the overdoped samples, a gradual and partial wipeout effect below about 80 K for the optimally doped ones, and very abrupt and full wipeout effect below about 40 K for the underdoped ones. The wipeout effect indicates a highly enhanced spectral weight of Cu spin fluctuations at a low frequency. We associate the wipeout effect with a Zn-induced local magnetism far above 40 K and with a localization effect below 40 K., 2 pages, 3 figures, accepted for publication in Physica C (LT23, Hiroshima 2002)

We report a Cu nuclear quadrupole resonance experiment on magnetic impurity Ni-substituted YBa 2 Cu 3 - x Ni x O 7 - Φ . The distribution of Ni-substituted sites and its effect on the Cu electron spin dynamics are investigated. Two samples with the same Ni concentration x = 0.10 and nearly the same oxygen content but different T c 's were prepared: One is an as-synthesized sample (7- δ=6.93) in an oxygen gas (T c 80 K), and the other is a quenched one (7-δ=6.92) in a reduced oxygen atmosphere (T c 70 K). The plane-site 6 3 Cu(2) nuclear spin-lattice relaxation for the quenched sample was faster than that for the as-synthesized sample, in contrast to the 6 3 Cu(1) relaxation that was faster for the as-synthesized sample. This indicates that the density of plane-site Ni(2) is higher in the quenched sample, contrary to the chain-site Ni(1) density, which is lower in the quenched sample. From the analysis in terms of the Ni-induced nuclear spin-lattice relaxation, we suggest that the primary origin of suppression of T c is associated with the nonmagnetic depairing effect of the plane-site Ni(2).

We report on a zero-field ${}^{63}\mathrm{Cu}$ nuclear quadrupole resonance (NQR) study of nonmagnetic Mg impurity substituted ${\mathrm{Cu}}_{1\ensuremath{-}x}{\mathrm{Mg}}_{x}{\mathrm{GeO}}_{3}$ (single crystals; the spin-Peierls transition temperature ${T}_{\mathrm{sp}}\ensuremath{\sim}14,$ 13.5, and 11 K for $x=0,$ 0.0043, and 0.020) in a temperature range from 4.2 to 250 K. We found that below ${T}^{*}\ensuremath{\sim}77 \mathrm{K},$ Cu NQR spectra are broadened and nonexponential Cu nuclear spin-lattice relaxation increases for undoped and more remarkably for Mg-doped samples. The results indicate that random lattice distortion and impurity-induced spins appear below ${T}^{*},$ which we associate with a precursor of the spin-Peierls transition. Conventional magnetic critical slowing down does not appear down to 4.2 K below ${T}_{\mathrm{sp}}.$

The time variation of the equation of state ($w_Q$) for the dark energy is analyzed by the current values of parameters $\Omega_Q $, $w_Q $ and their time derivatives. In the future, detailed feature of the dark energy could be observed, so we have considered the second derivatives of $w_Q$ for two types of potential: One is an inverse power-law type ($V=M^{4+\alpha}/Q^{\alpha}$) and the other is an exponential one ($V=M^4\exp{(\beta M/Q)}$). The first derivative $dw_Q/da$ and the second derivative $d^2 w_Q/da^2$ for both potentials are derived. The first derivative is estimated by the observed two parameters $\Delta=w_Q+1$ and $\Omega_Q$, with the assuming for $Q_0$. In the limit $\Delta \rightarrow 0$, the first derivative is null and, under the tracker approximation, the second derivative also becomes null. For the inverse power potential $V=M^{4+\alpha}/Q^{\alpha}$, the observed first and second derivatives are used to determine the potential parameter $M$ and $\alpha$. For the potential of $V=M^4\exp{(\beta M/Q)}$, the second derivative is estimated by the observed parameters $\Delta$, $\Omega_Q$ and $dw_Q/da$., Comment: 15 pages

We report a zero-field Cu nuclear quadrupole resonance (NQR) study on the effects of nonmagnetic Sr substitution for high-${T}_{c}$ superconductors, $\mathrm{Y}({\mathrm{Ba}}_{1\ensuremath{-}x}{\mathrm{Sr}}_{x}{)}_{2}{\mathrm{Cu}}_{4}{\mathrm{O}}_{8}$ ${(T}_{c}=82\char21{}80 \mathrm{K},$ for $x=0\ensuremath{-}0.4),$ using a spin-echo technique. The site-disordering and chemical pressure effects associated with doping Sr were observed in the broadened, shifted Cu NQR spectra. Nevertheless, the site disorder did not significantly affect the homogeneity of Cu electron spin dynamics, in contrast to the in-plane impurity. The peak shift of the Cu NQR spectrum due to Sr was different between the chain- and the plane-Cu sites, more remarkably than those under a hydrostatic physical pressure, suggesting anisotropic or nonuniform local structural strains. The small decrease of ${T}_{c}$ due to Sr can be traced back to either a cancellation effect on ${T}_{c}$ between the disorder and the pressure, or an anisotropic or nonuniform chemical pressure effect on ${T}_{c}.$

We present the planar 63Cu nuclear spin-lattice relaxation study of impurity-doped YBa2(Cu1-xMx)4O8 (M=Ni, Zn) at T=4.2-300 K with Cu nuclear quadrupole resonance (NQR) spin-echo technique. In the light of an impurity-induced NQR relaxation theory, we estimated the host Cu nuclear spin-lattice relaxation time (T1)HOST, the impurity-induced Cu nuclear spin-lattice relaxation time (t1), and the wipeout region around the impurity in the superconducting state. The pseudo spin-gap behavior of the host Cu antiferromagnetic spin fluctuation above Tc is not readily removed by a small amount of the impurity. The Zn-induced non-Korringa behavior of (T1)HOST below Tc is in sharp contrast to the doping effect of the magnetic impurity Ni., 5 pages, 4 figures. To be published in Physica C (ISS2000)

We studied low-frequency spin dynamics near the impurity-induced superconductor-to-insulator transition for underdoped high-Tc superconductor YBa2(Cu1-xMx)4O8 (M=Ni, Zn) using the Cu nuclear quadrupole resonance (NQR) spin-echo technique. We observed remarkable suppression of the normal-state pseudo spin-gap and a loss of Cu NQR spectrum intensity at low temperatures around the critical impurity concentration., Comment: 6 pages, 4 figures. To be published in J. Phys. Soc. Jpn. Vol.70, No.7 (2001)