62 research outputs found

    Conformal amplitude hierarchy and the Poincare disk

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    The amplitude for the singlet channels in the 4-point function of the fundamental field in the conformal field theory of the 2d O(n)O(n) model is studied as a function of nn. For a generic value of nn, the 4-point function has infinitely many amplitudes, whose landscape can be very spiky as the higher amplitude changes its sign many times at the simple poles, which generalize the unique pole of the energy operator amplitude at n=0n=0. In the stadard parameterization of nn by angle in unit of π\pi, we find that the zeros and poles happen at the rational angles, forming a hierarchical tree structure inherent in the Poincar\'{e} disk. Some relation between the amplitude and the Farey path, a piecewise geodesic that visits these zeros and poles, is suggested. In this hierarchy, the symmetry of the congruence subgroup Γ(2)\Gamma(2) of SL(2,Z)SL(2,\mathbb{Z}) naturally arises from the two clearly distinct even/odd classes of the rational angles, in which one respectively gets the truncated operator algebras and the logarithmic 4-point functions.Comment: 13 pages, 2 figures. see this version; corrections made; references adde

    Classes of low-frequency earthquakes based on inter-time distribution reveal a precursor event for the 2011 Great Tohoku Earthquake

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    Recently, slow earthquakes (slow EQ) have received much attention relative to understanding the mechanisms underlying large earthquakes and to detecting their precursors. Low-frequency earthquakes (LFE) are a specific type of slow EQ. In the present paper, we reveal the relevance of LFEs to the 2011 Great Tohoku Earthquake (Tohoku-oki EQ) by means of cluster analysis. We classified LFEs in northern Japan in a data-driven manner, based on inter-time, the time interval between neighboring LFEs occurring within 10 km. We found that there are four classes of LFE that are characterized by median inter-times of 24 seconds, 27 minutes, 2.0 days, and 35 days, respectively. Remarkably, in examining the relevance of these classes to the Tohoku-oki EQ, we found that activity in the shortest inter-time class (median 23 seconds) diminished significantly at least three months before the Tohoku-oki EQ, and became completely quiescent 30 days before the event (p-value = 0.00014). Further statistical analysis implies that this class, together with a similar class of volcanic tremor, may have served as a precursor of the Tohoku-oki EQ. We discuss a generative model for these classes of LFE, in which the shortest inter-time class is characterized by a generalized gamma distribution with the product of shape parameters 1.54 in the domain of inter-time close to zero. We give a possible geodetic interpretation for the relevance of LFE to the Tohoku-oki EQ

    Quantum Interactions of Topological Solitons from Electrodynamics

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    The Casimir energy for the classically stable configurations of the topological solitons in 2D quantum antiferromagnets is studied by performing the path-integral over quantum fluctuations. The magnon fluctuation around the solitons saturating the Bogomol'nyi inequality may be viewed as a charged scalar field coupled with an effective magnetic field induced by the solitons. The magnon-soliton couping is closely related to the Pauli Hamiltonian, with which the effective action is calculated by adapting the worldline formulation of the derivative expansion for the 2+1d quantum electrodynamics in an external field. The resulting framework is more flexible than the conventional scattering analysis based on the Dashen-Hasslacher-Neveu formula. We obtain a short-range attractive well and a universal long-range 1/r1/r-type repulsive potential between two solitons.Comment: 17 pages, 3 figures, added an experimental setup using a skyrmion racetrack; matches published versio

    ワカテ ショウニ ゲカイ ノ ECFMG certificate シュトク エノ チョウセン : ベイコク ショウニ ゲカ リンショウ リュウガク オ メザシテ

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    Recently, many Japanese pediatric surgeons undertake clinical training abroad, especially in the United States of America (USA) which is one of the most attractive country for advanced clinical training. Since the Japanese government introduced a 2-year mandatory residency program in 2004, it has become more and more important for busy Japanese residents to spent time efficiently in order to achieve ECFMG (Educational Commission For Foreign Medical Graduates) certification. ECFMG certification requires residents to pass both Step 1 and 2 of the United States Medical License Examination (USMLE). It is especially difficult to pass step2 CS (Clinical Skills) for many Japanese who are unfamiliar with the English language. For example, one of authors started to study for the USMLE in the 6th grade of the Japanese Medical School (MS4), passed step1 and step2 CK (Clinical Knowledge) during the 2-year mandatory intensive rotating residency program, and passed Step2 CS on the 3rd attempt during the general surgery residency program. This shows that a Japanese examinee can pass the ECFMG certificate even during a busy rotating residency program

    ショウチョウカンマク シボウ ニクシュ ノ 1レイ

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    We report a case of small intestinal mesenteric liposarcoma. An 84-year-old woman was admitted to our hospital with a chief complaint of abdominal distension and pointing out a tumor in her abdomen. On physical examination an adult’s head-sized tumor was palpated from the left upper portion of the pelvis. Abdominal computed tomography(CT)revealed the mass24×18×13cm in size which had clear borderline and smooth surface. Multi-detector-CT scan revealed a heterogeneously enhanced mass fed by the Superior mesenteric artery. With a clinical diagnosis of liposarcoma arisen from the small intestinal mesentery, the patient was operated on. The tumor was present in the mesentery of the small intestine and a removal of the tumor with associated resection of the small intestine was perfomed. The histological diagnosis was well-differentiated liposarcoma. The patient has been followed for nine months after the operation without evidence of local recurrence

    フクブ ショクドウ チョウフクショウ ニ タイシ フククウキョウカ テキシュツジュツ オ シコウ シタ 1レイ

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    A 9-year-old boy was admitted to the hospital for close exploration of cystic tumor of the esophagus ventral detected in the abdominal contrast CT scan during the investigation of hematuria. Upper gastrointestinal fluoroscopic and endoscopic examination with ultrasonography showed a cystic tumor with the diameter of 2cm and smooth surface in the abdominal esophagus. Laparoscopic surgery was performed under the diagnosis of abdominal esophageal duplication cyst. At surgery, the soft and well-defined mass was present in the abdominal esophagus ventral and continuous with the esophagus wall. Histopathological study showed the cystic wall was lined with the pseudostratified ciliated epithelium and subepithelial muscle layer. These findings indicated abdominal esophageal duplication cyst. He was discharged on postoperative day 8 with good postoperative course. Abdominal esophageal duplication cyst is a rare disease. Laparoscopic surgery, which has not seen attempted before this case, seems to be a useful treatment of abdominal esophageal duplication cyst

    ショウニ ノ タンカン カクチョウガタ スイ タンカン ゴウリュウ イジョウ セツジョレイ ニ ハツガン カンレン イデンシ HDAC ガ コウハツゲン シテイタ 1レイ

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    Pancreaticobiliary maljunction(PBM)is the congenital malformation that the junction of the pancreatic and bile ducts is located outside of the duodenal wall anatomically, so sphincter function preventing to mix the bile and pancreatic juice does not act. In PBM, the mutual reflux of bile and pancreatic juice induces various diseases and becomes the cause of biliary tract cancer generation. PBM is divided into PBM with the biliary dilatation and PBM without the biliary dilatation. From the perspective of carcinogenesis, surgery to separate the pancreatic juice and bile by excision of extrahepatic biliary tract and hepaticojejunostomy is commonly performed in the former, the treatment of the latter is controversial, for instance ; the only cholecystectomy should be performed and excision of extrahepatic biliary tract is unnecessary or excision of extrahepatic biliary tract and hepaticojejunostomy should be done. In addition, histone acetylation and histone deacetylation is one of the important regulatory mechanism of gene transcription, the error of the balance between histone acetyltransferase(HAT)and histone deacetylase(HDAC)leads to carcinogenesis. In other words, HDAC has a carcinogenic potential. Overexpression of HDAC was found in the both resected gallbladder and bile duct mucosa of infant PBM patient with the biliary dilatation performed the excision of extrahepatic biliary tract and hepaticojejunostomy in our department. Appropriate treatment for PBM has not been established yet, but even infant case with PBM has carcinogenesis potential just like this case. In conclusion, further accumulation of cases including PBM without the biliary dilatation was thought to be essential though the excision of extrahepatic biliary tract and hepaticojejunostomy still seems to be required for infant PBM patient with the biliary dilatation
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