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We study the symmetric nuclear matter using bare nucleon-nucleon ($NN$) interactions with finite particle-number approach within finite cubic boxes. Due to the $NN$ correlations originating from bare $NN$ interaction, two nucleons can be excited to the high-momentum region, leading to the increase of the kinetic energy in nuclear matter. We further consider the spin excitations in the nucleon pairs, where the spin of the two nucleons are changed, and this excitation is important for the tensor correlation. The unitary correlation operator method (UCOM) is used to treat the short-range correlation. The tail correction coming from the neighbouring boxes is also included. We demonstrate the contributions of various excitations of nucleon pairs as well as the tail correction to the total energy at the normal density. We also discuss the effects of UCOM and correlated nucleon pairs on the density dependence of the total energy. We calculate the equations of state of symmetric nuclear matter using two kinds of the Argonne potentials and the results agree with those from other many-body theories. The density dependences of the Hamiltonian components are also shown., Comment: 12 pages, 11figures, 1 table

We propose a new many-body method based on the correlation functions, in which the multiple products of the correlation functions are expanded into the many-body diagrams using the cluster expansion method and every diagram is independently optimized in the total-energy variation. We apply this idea to the tensor-optimized antisymmetrized molecular dynamics (TOAMD) using the bare nucleon-nucleon interaction and show the results of the $s$-shell nuclei within the triple products of the correlation functions of tensor and central-types. We evaluate the effect of the independent optimization of the many-body diagrams on the solutions. It is found that the triple products provides the sizable effect in the present scheme, which results in the good reproduction of the total energy and the Hamiltonian components of nuclei with respect to the few-body calculations., 12 pages, 13 figures

Background: The $^{44}$Ti nucleus has been known to have a $^{40}$Ca+$\alpha$ cluster structure, and inversion doublet structure has been observed; however, $\alpha$ cluster structure tends to be washed out when the breaking of the $\alpha$ cluster is allowed due to the spin-orbit interaction. Nevertheless, $\alpha$ clustering in medium-heavy nuclei is quite a hot subject recently. Purpose: The tensor interaction has been known to play an essential role in the strong binding of the $^4$He nucleus, which induces the two-particle-two-hole (2p2h) excitation. Since this excitation is blocked when another nucleus approaches, it is worthwhile to show whether the tensor effect works to keep the distance between $^4$He and $^{40}$Ca and becomes the salvation of the clustering in $^{44}$Ti. Methods: The spin-orbit effect is included in the cluster model by using the antisymmetrized quasi cluster model (AQCM) developed by the authors. We have also developed an improved version of the simplified method to include the tensor contribution ($i$SMT), which allows us to estimate the tensor effect within the cluster model. The competition of these two is investigated in the medium-heavy mass region for the first time. Results: According to AQCM, the spin-orbit interaction completely breaks the $\alpha$ cluster and restores the symmetry of $jj$-coupling shell model when the $\alpha$ cluster approaches the $^{40}$Ca core. On the other hand, $i$SMT gives a large distance between $\alpha$ and $^{40}$Ca due to the tensor effect. Conclusions: In $^{44}$Ti, because of the strong spin-orbit and tensor contributions, two completely different configurations ($jj$-coupling shell model and cluster states) almost degenerate, and their mixing becomes important., Comment: 7 pages, 4 figures

We extend high-momentum antisymmetrized molecular dynamics (HMAMD) by incorporating the short-range part of the unitary correlation operator method (UCOM) as the variational method of finite nuclei. In this HMAMD+UCOM calculation of light nuclei, HMAMD is mainly in charge of the tensor correlation with up to four-body correlation, while the short-range correlation is further improved by using UCOM. The binding energies of the $^3$H and $^4$He nuclei are calculated with HMAMD+UCOM using the AV8$'$ bare nucleon–nucleon ($NN$) interaction. The different roles of the short-range and tensor correlations from HMAMD and UCOM are analyzed in the numerical results. Compared with previous calculations based on different variational methods, this newly extended HMAMD+UCOM method can almost provide consistent results with ab initio results.

A 72-year-old man had undergone uncomplicated endoscopic submucosal dissection (ESD) with en bloc resection of a localized 20-mm IIc lesion in the anterior wall of the gastric angle. Twenty-eight days later, he was re-admitted with epigastric pain of one-week duration. Contrast-enhanced computed tomography (CT) revealed a 60-mm mass bordered by viscera; repeat endoscopy confirmed a smooth elevated submucosal tumor at the greater curvature on the oral side of the post-ESD ulcer. We diagnosed him with a perigastric abscess as a complication of ESD and performed endoscopic ultrasound-guided drainage. Subsequently, the symptoms and blood inflammatory parameters improved, and follow-up CT showed the disappearance of the abscess.

Background and study aims Despite the information regarding extravasation from contrast-enhanced computed tomography (CECT), the detectability of the target diverticulum by colonoscopy remains unsatisfactory in colonic diverticular bleeding (CDB). The lack of common signs recognizable on CT and endoscopic images makes it difficult to set a region of interest; however, this can be overcome with the “step-clipping” method, a strategic marking technique for revealing the target. We aimed to investigate the clinical performance of the step-clipping method in patients with CDB. Patients and methods Eighty-seven patients diagnosed with CDB with extravasation using CECT who underwent colonoscopy between August 2007 and February 2020 were included. Patients were divided into two categories: the traditional group (those who underwent colonoscopy from August 2007 to May 2017, n = 54) and the step-clipping group (those who underwent colonoscopy from June 2017 to February 2020, n = 33). Results The detection rate for the responsible diverticulum was significantly higher in the step-clipping group than in the traditional group (94 % vs 63 %; P = .0013). The step-clipping group had a shorter average search time during colonoscopy (9.6 vs 40.5 minutes; P Conclusions Colonoscopy using the step-clipping method can improve the detectability of the target lesion within a shorter time, thus leading to lower re-bleeding rates and earlier hospital discharge.

A man in his 40s with no remarkable past medical history was referred to our hospital with acute exacerbation of nonspecific epigastric pain by another hospital on the morning of the day of presentation. Though vital signs were stable, tenderness and guarding were observed over the entire abdomen. Contrast-enhanced computed tomography (CT) revealed a giant retroperitoneal hematoma due to a ruptured aneurysm close to the superior mesenteric artery. Emergency angiography of the superior mesenteric artery detected a ruptured 2-mm pseudoaneurysm of the posterior superior pancreaticoduodenal artery, for which embolization was immediately performed. The postoperative course was good, with the patient complaining only of transient abdominal pain due to exclusion of the hematoma on hospital day 6. His clinical symptoms disappeared with conservative treatment, and the patient was discharged on hospital day 18. Complete occlusion of the aneurysm and reduction of the hematoma was confirmed on follow-up CT. Pancreaticoduodenal artery aneurysm is an uncommon visceral artery aneurysm, and ruptured aneurysms typically result in fatal hemorrhage and high mortality. We herein report a case of ruptured aneurysm of the posterior pancreaticoduodenal artery where emergency transcatheter arterial embolization was able to save the patient's life. We also review 116 cases of pancreaticoduodenal artery aneurysm reported in Japanese literature.

We propose a new variational method for describing nuclear matter from nucleon-nucleon interaction. We use the unitary correlation operator method (UCOM) for central correlation to treat the short-range repulsion and further include the two-particle two-hole (2p2h) excitations of nucleon pair involving a large relative momentum, which is called 'high-momentum pair'(HM). We describe nuclear matter in finite size with finite particle number on periodic boundary condition and increase the 2p2h configurations until we get the convergence of the total energy per particle. We demonstrate the validity of this 'UCOM+HM' framework by applying it to the symmetric nuclear and neutron matters with the Argonne V4$^\prime$ potential having short-range repulsion. The nuclear equations of state obtained in UCOM+HM are fairly consistent to those of other calculations such as Brueckner-Hartree-Fock and auxiliary field diffusion Monte Carlo in the overall density region., Comment: 12 pages, 24 figures

症例は71歳，女性．右乳房A>C領域に拍動を有する鶉卵大の腫瘤を触知した．超音波検査で血管と思われる無エコー域を血栓と思われる低エコー域が層状に被包する脈瘤を認め，ドプラ超音波で無エコー域内に明瞭な血流と拍動を認めた．造影CT検査で腫瘤への流入血管は内胸動脈と外側胸動脈の分枝と確認した．乳腺仮性動脈瘤の診断で摘出術を施行した．摘出標本では比較的太い血管を器質化した血栓が層状に被包する腫瘤であった．病理検査で内膜および中膜が破綻した血管とそれを被包する血栓と結合織を認め，乳腺仮性動脈瘤と診断した．乳腺仮性動脈瘤は本邦報告例のない極めて稀な疾患で，文献的考察を加え報告する．

Plummer-Vinson症候群は嚥下障害，鉄欠乏性貧血および舌炎を主徴とする症候群で，下咽頭癌や頸部食道癌との合併が多いとされる．今回われわれは，Plummer-Vinson症候群に発症した胃癌の1例を経験したので報告する．症例は62歳，男性．30年前より貧血，嚥下困難を自覚．最近になって嚥下困難が増悪したため来院．血液検査にて鉄欠乏性貧血を認めた．上部消化管精査にて食道入口部に膜様狭窄（食道web）を認めた．また胃体部大彎にI型腫瘍を認め，組織学的に胃癌と診断された．Plummer-Vinson症候群に発症した胃癌の診断で根治的胃亜全摘術を施行した．病理組織学的に乳頭腺癌であった．現在再発兆候無く，鉄剤の内服にて貧血および嚥下困難は認めていない．今回，Plummer-Vinson症候群と胃癌との明確な関連性は指摘できなかったが，本症候群の患者に対しては，胃癌の発症も念頭に置いた診療が必要と考えられた．

We consider an array of Gaussian functions in order to account for the self-energy of an element, and we derive an expression for its electrostatic energy. In this expression, the number of dimensions of space and the periodicity can be generalized to take arbitrary real number values. The electrostatic energy evaluated in this manner increases with the number of dimensions of the periodicity, in contrast to the irregular dependence of the electrostatic energy evaluated from an expression for point charges, like in the Ewald method. In the limit of an array of δ functions, the electrostatic energy has a singularity at (d - 1)-dimensional periodicity in d-dimensional space, due to the self-energy of an element.

We propose a definitive expression for the electrostatic energy of an aggregate of point charges with periodicity in a uniform background. We correctly treat the long-range property of the Coulomb interaction on the basis of the Yukawa interaction. In the derivation, we define a dimension-dependent function which solves the divergence problem in the sum of Coulomb potentials. We also derive an expression for the sum of 1/r ν -type potentials. We recognize the validity of our expression for electrostatic energies, applying it to typical crystals in a uniform background, and show that electrostatic energies do not depend in a simple manner on the dimension of periodicity. We also investigate α-cluster matter as an example of Lennard-Jones systems.

We propose a definitive expression to evaluate electrostatic energies under periodic conditions, starting from the Yukawa potential with a finite range and summing up positive and negative contributions separately. We find a dimension-dependent function that can be used to solve problems concerning divergences and ambiguities in the direct sum of Coulomb potentials. The infinite-range limit of this function leads to a universal constant independent of lattice structure, which reveals the origin of ambiguities from conditionally convergent series in the sum of Coulomb potentials.

DC magnetron sputtering is assisted by microwave plasma to achieve high sputter deposition rates at low gas pressure. Microwave plasma is produced around a cylindrical multipolar magnetron arrangement and utilized for DC magnetron sputtering deposition. The deposition rate of aluminum films is more than 80 nm/min even at a low gas pressure of 0.2 mTorr. Optical emission measurements of aluminum ions and neutral lines indicate enhancement of ionization of the sputtered atoms.

New macrocyclic dinucleating ligands have been easily synthesized by Schiff-base condensation reaction with the appropriate aldehyde and amine using the boric ion template method. The ligands have two N2O2 metal-binding sites which are doubly linked to each other with methylene spacers. The ligands chelate with Co2+, Cu2+ and Ni2+ to form dimetallic compounds in high yields.

We consider clusterized nucleonic matter with crystal structure which is described by Bloch function. By using Bloch function, we can describe two extreme states, isolated clusterized matter and uniform matter, in low and high density, respectively, and also intermediate states continuously. We treat not only α-cluster matter but also 10He-and 16O-cluster matter by introducing p-wave Bloch function orthogonal to s-wave Bloch function. P-shell cluster-like density fluctuation arises below a certain critical density as well as s-shell cluster-like one.

Tubular carcinoma of the breast is a rare type of breast carinoma which has characteristic histologic findings, especially pure type tubular carcinoma in that lymp node metastases rarely occur and the prognosis is good. We report a case of resected pure type tubular carcinoma of the breast with lymph node metastasis. A 55-year-old woman was referred to the hospital because of a tumor formation at her left breast. The tumor shadow with spicula was identified by a mammogram, but the tumor could not be diagnosed as malignancy by an aspiration cytology. By an excisional biopsy, the tumor was diagnosed as tubular carcinoma. The patient underwent a mastectomy with lymph nodes dissection. Postoperative histological findings revealed pure type tubular carcinoma with axillary lymph node metastasis. Since lymph node metastasis is detected in a pure type tubular carcinoma like in this case, tubular carcinoma should be dealt with the same manner as other invasive carcinomas of the breast are treated.

The clustering structure of neutron dripline nucleus 19 B, which is predicted by the AMD model and the molecular orbital model, is investigated by studying the fragmentation reaction of 19 B. We compare 19 B fragmentation with 13 B fragmentation in 19 B+ 14 N and 13 B + 14 N reactions at 35 MeV/nucleon by using antisymmetrized molecular dynamics, where 13 B has no clustering features in its structure. We find that the cluster structure of the 19 B nucleus is reflected in its fragmentation, since more He and Li isotopes are produced in the 19 B fragmentation in comparison with the case in 13 B fragmentation. Furthermore, we compare the 19 B fragmentation with 12 C fragmentation in the 14 N-target reaction at 35 MeV/nucleon. In the case of 12 C fragmentation, the existence of the clustering excited states of 12 C significantly affects the fragmentation process, since the production of α particles is largely due to fragmentation through these clustering excited states, while in the case of 19 B fragmentation, we cannot find such clustering excited states through which 19 B breaks up into clusters.

Fragmentation in heavy-ion reactions in the intermediate energy region is studied with antisymmetrized molecular dynamics (AMD). AMD is extended to introduce the wave packet diffusion effect as a stochastic branching process, which is essential for the description of the multifragmentation and the quantum statistical property.

In order to study effects of clustering of colliding nuclei in the fragmentation process, the fragmentation of the {sup 14}N+{sup 12}C reaction at 35 MeV/nucleon is analyzed by antisymmetrized molecular dynamics. It is found that {sup 4}He fragments from {sup 12}C fragmentation are much more abundant than those from {sup 14}N fragmentation. Characters of {sup 4}He fragments from {sup 12}C fragmentation are investigated and it is found that this abundance in {sup 12}C fragmentation results from the three-alpha breakup in a short time scale where the excited states with excitation energy 7{endash}15 MeV play an important role. {copyright} {ital 1996 The American Physical Society.}

Canonical transient receptor potential (TRPC) channels control influxes of Ca 2+ and other cations that induce diverse cellular processes upon stimulation of plasma membrane receptors coupled to phospholipase C (PLC). Invention of subtype-specific inhibitors for TRPCs is crucial for distinction of respective TRPC channels that play particular physiological roles in native systems. Here, we identify a pyrazole compound (Pyr3), which selectively inhibits TRPC3 channels. Structure-function relationship studies of pyrazole compounds showed that the trichloroacrylic amide group is important for the TRPC3 selectivity of Pyr3. Electrophysiological and photoaffinity labeling experiments reveal a direct action of Pyr3 on the TRPC3 protein. In DT40 B lymphocytes, Pyr3 potently eliminated the Ca 2+ influx-dependent PLC translocation to the plasma membrane and late oscillatory phase of B cell receptor-induced Ca 2+ response. Moreover, Pyr3 attenuated activation of nuclear factor of activated T cells, a Ca 2+ -dependent transcription factor, and hypertrophic growth in rat neonatal cardiomyocytes, and in vivo pressure overload-induced cardiac hypertrophy in mice. These findings on important roles of native TRPC3 channels are strikingly consistent with previous genetic studies. Thus, the TRPC3-selective inhibitor Pyr3 is a powerful tool to study in vivo function of TRPC3, suggesting a pharmaceutical potential of Pyr3 in treatments of TRPC3-related diseases such as cardiac hypertrophy.

Tribological phenomena usually occur at a solid surface or an interface of solids. To carefully examine a tribological phenomenon, information on the state at the surface or the interface must be tried to be gotten from different angles. Estimations of the state, however, are generally considered to be difficult because there are few methods suit for adequately picking up the information on profiles and/or properties of the only nearest region to the surface. Especially for the case that the target is at the interface of metals, the estimation is more difficult because a standard electron beam cannot penetrate into either of the metal. The authors have, accordingly, developed a new estimation method applying a ‘neutron reflectometry’ to such a metal surface or a metal-metal interface. The reflectometry is suitable for analysis of vertical structures of the nearest regions to a surface as less than 1 μm. In addition, since a neutron beam can penetrate into many kinds of common metals, the estimation by the neutron reflectometry can be useful even for the metal-metal interface. In this paper, we report some results obtained by some of several basic experiments on neutron reflectometry. Surface profiles and ultra-thin film thickness of PFPE lubricant at a metal surface and/or a metal-metal interface were estimated in the study.Copyright © 2005 by ASME

Dihydropyrimidine dehydrogenase (DPD) is an enzyme that catabolizes 5-fluorouracil (5-FU), which is widely used for chemotherapy in patients with advanced colorectal cancer (CRC). However, the clinical importance of tumor dihydropyrimidine dehydrogenase (DPD) expression in patients with CRC treated with 5-FU remains unclear.We investigated DPD activities in normal mucosa (N) and tumors (T) by enzyme-linked immunosorbent assay (ELISA) in 64 surgically resected patients with Dukes' C CRC who were treated orally with postoperative adjuvant FU-based chemotherapy. We also immunohistochemically investigated DPD expression in these specimens. The clinicopathological importance of DPD activity and expression was evaluated in the patients.Positive DPD expression was detected in 28 tumors (43.8%) and tumor DPD activity significantly correlated with tumor DPD immunoreactivity (p=0.0121). Further, tumor DPD activity and immunoreactivity also correlated with lymph node metastatic status (p=0.0409). The disease-free survival rate of patients with positive-tumor DPD expression was significantly worse than that of patients with negative-tumor DPD expression (39.3% vs. 72.2%, p=0.0127). However, DPD activity in tumors or normal mucosa did not correlate with patient prognosis. Tumor DPD expression appeared to be an important poor prognostic factor in patients with Dukes' C CRC by multivariate analysis (p=0.013).Immunohistochemical DPD expression in tumors is a useful prognostic parameter in patients with Dukes' C CRC treated with postoperative adjuvant FU-based chemotherapy.

Mg-doped high-In-content In x Ga1− x N (x ∼ 0.35) thin films were grown on a c-face sapphire substrate using an MBE apparatus having dual RF nitrogen plasma cells. The films showed p-type conduction under certain cell temperatures of Mg. The p-type conduction was confirmed by electrolyte-based capacitance–voltage measurement on an In x Ga1− x N:Mg/In2O3/sapphire structure, in addition to thermo-electromotive force measurements.

We investigate the fragmentation mechanism reflecting the cluster structure of the ${}^{19}\mathrm{B}$ nucleus. We perform antisymmetrized molecular dynamics (AMD) calculations of ${}^{19}\mathrm{B}{+}^{14}\mathrm{N}$ and ${}^{13}\mathrm{B}{+}^{14}\mathrm{N}$ reactions, and compare ${}^{19}\mathrm{B}$ fragmentation with ${}^{13}\mathrm{B}$ fragmentation. The neutron drip-line nucleus ${}^{19}\mathrm{B}$ has been predicted to have a well-developed cluster structure in its ground state while the neutron closed-shell nucleus ${}^{13}\mathrm{B}$ has no clustering features in its structure. The clustering structure of ${}^{19}\mathrm{B}$ is reflected in its fragmentation as the dynamical cluster breakup into He and Li isotopes, depending on the incident energy. In the low-incident-energy region around 30 MeV/nucleon, dynamical cluster breakup of ${}^{19}\mathrm{B}$ occurs and brings about an abundance of He and Li isotopes in ${}^{19}\mathrm{B}$ fragmentation compared with those in ${}^{13}\mathrm{B}$ fragmentation. In the high-incident-energy region above 50 MeV/nucleon, dynamical cluster breakup of ${}^{19}\mathrm{B}$ hardly occurs and the cluster structure of the ${}^{19}\mathrm{B}$ nucleus is not reflected in its fragmentation. We suggest here the coincident experiment between He and Li isotopes as an experimental way to confirm whether the ${}^{19}\mathrm{B}$ nucleus has a cluster structure in its ground state or not.

We consider clusterization of nuclear matter in low-density region. In general, nucleons are considered as independent particles moving in some average potential created by all the nucleons. On the basis of this idea, the ground state of nuclear matter is believed to be uniform and to be the plane-wave state with Fermi sphere near the saturation density such as in the interior region of nuclei. On the other hand, there is the strong correlation forming an α cluster which is observed especially in excited states of 4n-nuclei. 1) α-cluster-like density-fluctuated states of nuclear matter has been studied by several authors, 2), 3) and they suggest that α-clustering effects may become important in the low-density region such as a surface of nuclei. The purpose of the present work is to investigate clustering effects of nuclear matter under the neutron-rich situation. For this purpose, we extend the procedure in Ref. 2) where single-particle states of α-cluster-like matter with a simple cubic lattice are described by Bloch function (B.F.) of the linear combination of s-wave function (s-wave B.F.) in analogy with electrons in lattice