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Hybridization of Bogoliubov quasiparticles (BQPs) between the CuO_{2} layers in the triple-layer cuprate high-temperature superconductor Bi_{2}Sr_{2}Cu_{2}Cu_{3}O_{10+δ} is studied by angle-resolved photoemission spectroscopy (ARPES). In the superconducting state, an anticrossing gap opens between the outer- and inner-BQP bands, which we attribute primarily to interlayer single-particle hopping with possible contributions from interlayer Cooper pairing. We find that the d-wave superconducting gap of both BQP bands smoothly develops with momentum without an abrupt jump in contrast to a previous ARPES study. Hybridization between the BQPs also gradually increases in going from the off nodal to the antinodal region, which is explained by the momentum dependence of the interlayer single-particle hopping. As possible mechanisms for the enhancement of the superconducting transition temperature, the hybridization between the BQPs as well as the combination of phonon modes of the triple CuO_{2} layers and spin fluctuations represented by a four-well model are discussed.
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An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Colorectal cancer metastasis to the retroperitoneum, especially solitary metastasis allowing curative resection, is rare. We report a case of complete resection of retroperitoneal metachronous solitary metastasis from caecal cancer without distant metastasis. An 80-year-old woman with caecal cancer underwent laparoscopic ileocaecal resection with regional lymph node dissection. According to the eighth edition of the TNM classification, the pathological diagnosis was stage IIA (T3N0M0). Six months following the surgery, computed tomography revealed a solitary mass of 2cm diameter, dorsal to the right kidney. A second procedure for the removal of the tumour was performed. The lesion was pathologically diagnosed as a metachronous solitary retroperitoneal metastasis from caecal cancer. The patient is surviving and free from recurrence 17 months following the second procedure.
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Neoplasias del Ciego/patología , Ciego , Íleon , Neoplasias Retroperitoneales , Anciano de 80 o más Años , Ciego/diagnóstico por imagen , Ciego/patología , Ciego/cirugía , Femenino , Humanos , Íleon/diagnóstico por imagen , Íleon/patología , Íleon/cirugía , Laparoscopía , Neoplasias Retroperitoneales/diagnóstico , Neoplasias Retroperitoneales/patología , Neoplasias Retroperitoneales/secundario , Neoplasias Retroperitoneales/cirugíaRESUMEN
Conventional superconductivity is caused by electron-phonon coupling. The discovery of high-temperature superconductors raised the question of whether such strong electron-phonon coupling is realized in cuprates. Strong coupling with some collective excitation mode has been indicated by a dispersion "kink". However, there is intensive debate regarding whether the relevant coupling mode is a magnetic resonance mode or an oxygen buckling phonon mode. This ambiguity is a consequence of the energy of the main prominent kink. Here, we show a new landscape of dispersion kinks. We report that heavily overdoping a Bi2Sr2CaCu2O8+δ superconductor results in a decline of the conventional main kink and a rise of another sharp kink, along with substantial energy shifts of both. Notably, the latter kink can be ascribed only to an oxygen-breathing phonon. Hence, the multiple phonon branches provide a consistent account of our data set on the multiple kinks. Our results suggest that strong electron-phonon coupling and its dramatic change should be incorporated into or reconciled with scenarios for the evolution of high-T c superconductivity.
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We have carried out hard x-ray photoemission spectroscopy (HAXPES) of Yb1-x Zr x B12 ([Formula: see text]) to study the effects of electron doping on the Kondo insulator YbB12. The Yb valences of Yb1-x Zr x B12 at 300 K estimated from the Yb 3d HAXPES spectra decreased after substituting Yb with Zr from 2.93 for YbB12 to 2.83 for Yb0.125Zr0.875B12. A temperature dependent valence decrease was found upon cooling for all doping concentrations. We found peak shifts of the B 1s and Zr 3d5/2, and Yb3+ 4f spectra toward the deeper binding-energy with increasing Zr concentration, which indicates a shift of the Fermi level to the higher energy and that of the Yb 4f hole level close to the Fermi level, respectively, due to electron doping. These results qualitatively show the enhanced hybridization between the Yb 4f and conduction-band states with Zr substitution, consistent with magnetic susceptibility measurements.
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The estimation of energy expenditure (EE) of grazing animals is of great importance for efficient animal management on pasture. In the present study, a method is proposed to estimate EE in grazing animals based on measurements of body acceleration of animals in combination with the conventional Agricultural and Food Research Council (AFRC) energy requirement system. Three-dimensional body acceleration and heart rate were recorded for tested animals under both grazing and housing management. An acceleration index, vectorial dynamic body acceleration (VeDBA), was used to calculate activity allowance (AC) during grazing and then incorporate it into the AFRC system to estimate the EE (EE derived from VeDBA [EE]) of the grazing animals. The method was applied to 3 farm ruminant species (7 cattle, 6 goats, and 4 sheep). Energy expenditure based on heart rate (EE) was also estimated as a reference. The result showed that larger VeDBA and heart rate values were obtained under grazing management, resulting in greater EE and EE under grazing management than under housing management. There were large differences between the EE estimated from the 2 methods, where EE values were greater than EE (averages of 163.4 and 142.5% for housing and grazing management, respectively); the EE was lower than the EE, whereas the increase in EE under grazing in comparison with housing conditions was larger than that in EE. These differences may have been due to the use of an equation for estimating EE derived under laboratory conditions and due to the presence of the effects of physiological, psychological, and environmental factors in addition to physical activity being included in measurements for the heart rate method. The present method allowed us to separate activity-specific EE (i.e., AC) from overall EE, and, in fact, AC under grazing management were about twice times as large as those under housing management for farm ruminant animals. There is evidence that the conventional energy system can predict fasting metabolism and the AC of housed animals based on accumulated research on energy metabolism and that VeDBA can quantify physical activity separately from other factors in animals on pasture. Therefore, the use of the VeDBA appears to be a precise way to predict activity-specific EE under grazing conditions, and the method incorporating acceleration index data with a conventional energy system can be a simple and useful method for estimation of EE in farm ruminants on pastures.
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Metabolismo Energético/fisiología , Actividad Motora/fisiología , Rumiantes/fisiología , Crianza de Animales Domésticos , Animales , Femenino , Frecuencia Cardíaca/fisiologíaRESUMEN
AIM: Ulcerative colitis (UC) is considered to be a disease of continuous mucosal inflammation extending proximally from the rectum. However, appendiceal orifice inflammation (AOI) is a skip lesion with segments of continuous involvement from the rectum. The aim of this study was to examine the clinical characteristics and clinical course, particularly focused on proximal extension, of UC in patients with AOI. METHOD: A retrospective evaluation of patients with UC who underwent total colonoscopy at the Department of Surgical Oncology, The University of Tokyo, from 2004 to 2014. The degree of AOI was graded endoscopically as follows: 0 (no inflammation); 1 (slight oedema); 2 (moderate inflammation); and 3 (marked inflammation). A total of 189 patient records were reviewed retrospectively. The presence of AOI was analysed with regard to the clinical information of each patient, and its association with proximal extension of proctitis or left-sided colitis was evaluated. RESULTS: Of 189 patients with UC who underwent total colonoscopy at our institution, 92 were diagnosed with pancolitis, 50 with left-sided colitis and 47 with proctitis. Endoscopic findings of AOI were observed in 26 patients, including 11 (12.0%) with pancolitis, six (12.0%) with left-sided colitis and nine (19.1%) with proctitis. During follow up, proximal extension of the disease occurred in all nine patients with proctitis AOI. CONCLUSION: AOI is more frequently observed in patients with proctitis. Our results showed correlations between AOI and subsequent proximal extension of mucosal inflammation in patients with proctitis.
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Apendicitis/patología , Colitis Ulcerosa/patología , Colon/patología , Colonoscopía , Proctitis/patología , Recto/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Apéndice/patología , Niño , Colon Descendente/patología , Colon Sigmoide/patología , Femenino , Humanos , Inflamación , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Adulto JovenRESUMEN
In the hole-doped cuprates, a small number of carriers suppresses antiferromagnetism and induces superconductivity. In the electron-doped cuprates, on the other hand, superconductivity appears only in a narrow window of high-doped Ce concentration after reduction annealing, and strong antiferromagnetic correlation persists in the superconducting phase. Recently, Pr(1.3-x)La0.7Ce(x)CuO4 (PLCCO) bulk single crystals annealed by a protect annealing method showed a high critical temperature of around 27 K for small Ce content down to 0.05. Here, by angle-resolved photoemission spectroscopy measurements of PLCCO crystals, we observed a sharp quasi-particle peak on the entire Fermi surface without signature of an antiferromagnetic pseudogap unlike all the previous work, indicating a dramatic reduction of antiferromagnetic correlation length and/or of magnetic moments. The superconducting state was found to extend over a wide electron concentration range. The present results fundamentally challenge the long-standing picture on the electronic structure in the electron-doped regime.
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AIM: The rate of extension of proctitis in Western countries has been reported, but no data regarding long-term follow-up have been described for the Japanese population. Additionally, patients with long-standing or extensive ulcerative colitis have an increased risk for developing colorectal cancer. This study evaluated both the rate of extension of the disease and the development of neoplasia among patients with an initial diagnosis of ulcerative proctitis. METHOD: We retrospectively investigated the medical charts of patients with proctitis from 1979 to 2014. The primary focus of this research was the extension of the inflammatory area. The secondary focus included risk factors for disease extension and the development of neoplasia. RESULTS: Sixty-six patients satisfied the inclusion criteria. Proximal extension of the disease occurred in 34 patients: 19 patients had left-sided colitis and 15 had pancolitis. According to a multivariate analysis, disease extension was significantly higher in patients with disease onset before 25 years of age (P-value = 0.043). The cumulative rates of disease extension at 10 and 20 years were 33.8% and 52.2%, respectively. Three patients were diagnosed with dysplasia during follow-up, all of whom experienced disease extension before the development of dysplasia. CONCLUSION: The rate of extension of ulcerative colitis in the Japanese population was comparable to that in Western countries. A younger age of disease onset was associated with disease extension. Extension of proctitis may be associated with an increased risk of colorectal cancer.
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Neoplasias Colorrectales/etiología , Progresión de la Enfermedad , Proctocolitis/patología , Adulto , Factores de Edad , Edad de Inicio , Neoplasias Colorrectales/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Japón/epidemiología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Proctocolitis/complicaciones , Proctocolitis/epidemiología , Estudios Retrospectivos , Factores de RiesgoRESUMEN
BACKGROUND: Optimal design of stents for a cerebral aneurysm is desired for efficient flow reduction in the aneurysm. OBJECTIVE: In this study, we aimed to optimize stent design at several porosities, estimate the influence of stent design on aneurysm flow, and evaluate the ability of stents to reduce flow. METHODS: Stent models were constructed as sets of squares or rectangles in the necks of a two-dimensional (2D) and realistic aneurysm. Then, automated optimization was performed using a combination of simulated annealing and lattice Boltzmann flow simulation. RESULTS: By simulated annealing, stents were gradually modified to reduce the average velocity in an aneurysm. As a result of optimization, stents of all porosities demonstrated an inhomogeneous distribution with dense struts in the inflow area. Flow reduction was increased compared with the initial stent. Under the condition of high porosity, flow reduction by the stent drastically increased as porosity decreased. Under low porosity, the increase of velocity reduction was moderate even as porosity decreased. CONCLUSIONS: Optimization can enhance flow reduction by stents. However, the increase in reduction associated with decreasing porosity is moderate under lower-porosity conditions. This threshold may help in the choice of stent porosity for each specific aneurysm.
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Aneurisma Intracraneal/cirugía , Porosidad , Diseño de Prótesis/métodos , Stents , Circulación Cerebrovascular/fisiología , Humanos , HidrodinámicaRESUMEN
We report peculiar momentum-dependent anisotropy in the superconducting gap observed by angle-resolved photoemission spectroscopy in BaFe2(As(1-x)P(x))2 (x = 0.30, Tc = 30â K). Strongly anisotropic gap has been found only in the electron Fermi surface while the gap on the entire hole Fermi surfaces are nearly isotropic. These results are inconsistent with horizontal nodes but are consistent with modified s ± gap with nodal loops. We have shown that the complicated gap modulation can be theoretically reproduced by considering both spin and orbital fluctuations.
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WHAT IS KNOWN AND OBJECTIVE: Patients' poor adherence to medications is reported to be related to the individual patients' beliefs and cognitions and their trust of the medical staff. However, the causes of the two forms of non-adherence, intentional and unintentional behaviours, have yet to be clarified. This study compared psychological latent factors associated with intentional and unintentional non-adherence to chronic medication regimens, focusing on the potential effects of (i) patients' dissatisfaction with treatment and their relationships with the medical staff and (ii) patients' subliminal rational thinking processes, which weighed the positive values such as their expectations of benefits from treatment against negative values such as their dissatisfaction. METHODS: Two cross-sectional surveys were undertaken of patients given medications for chronic diseases, using a questionnaire developed and validated in this study. One survey was undertaken in three hospitals and the other survey, online throughout Japan. We scored the individual latent factors using the questionnaire and calculated the differential score between two negatively correlated latent factors to quantify patients' subliminal rational thinking process. We compared the adjusted odds ratio (OR) of latent factors between intentional and unintentional non-adherence to medication in both surveys. RESULTS AND DISCUSSION: Of the eligible subjects, 149 hospitalized patients and 524 survey participants completed the questionnaire. Intentional non-adherence was associated with patient dissatisfaction with treatment including interpersonal relationships with medical staff in both hospitalized patients and online survey participants (95% confidence interval of adjusted OR for Dissatisfaction, 1·20-16·26 in the hospital-based survey and 1·33-3·45 in the online survey). In both surveys, intentional non-adherence was significantly associated with the differential score between two negatively correlated latent factors, Willingness and Dissatisfaction (P = 0·02 in the hospital-based survey and P < 0·001 in the online survey). However, these associations were not evident in unintentionally non-adherent patients. WHAT IS NEW AND CONCLUSIONS: Patients' dissatisfaction and their resulting rational judgments are unique, consistent determinants of intentional non-adherence to medications, but not of unintentional non-adherence.
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Juicio , Cumplimiento de la Medicación , Satisfacción del Paciente , Adulto , Anciano , Enfermedad Crónica/tratamiento farmacológico , Estudios Transversales , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Relaciones Profesional-Paciente , Encuestas y CuestionariosRESUMEN
An energy gap is, in principle, a dominant parameter in superconductivity. However, this view has been challenged for the case of high-Tc cuprates, because anisotropic evolution of a d-wave-like superconducting gap with underdoping has been difficult to formulate along with a critical temperature Tc. Here we show that a nodal-gap energy 2ΔN closely follows 8.5 kBTc with underdoping and is also proportional to the product of an antinodal gap energy Δ(*) and a square-root superfluid density âPs for Bi2Sr2CaCu2O8+δ, using low-energy synchrotron-radiation angle-resolved photoemission. The quantitative relations imply that the distinction between the nodal and antinodal gaps stems from the separation of the condensation and formation of electron pairs, and that the nodal-gap suppression represents the substantial phase incoherence inherent in a strong-coupling superconducting state. These simple gap-based formulae reasonably describe a crucial part of the unconventional mechanism governing Tc.
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We report the first observation of the multilayer band splitting in the optimally doped trilayer cuprate Bi2Sr2Ca2Cu3O(10+δ) (Bi2223) by angle-resolved photoemission spectroscopy. The observed energy bands and Fermi surfaces are originated from the outer and inner CuO2 planes (OP and IP). The OP band is overdoped with a large d-wave gap around the node of Δ0â¼43 meV while the IP is underdoped with an even large gap of Δ0â¼60 meV. These energy gaps are much larger than those for the same doping level of the double-layer cuprates, which leads to the large Tc in Bi2223. We propose possible origins of the large superconducting gaps for the OP and IP: (1) minimal influence of out-of-plane disorder and a proximity effect and (2) interlayer tunneling of Cooper pairs between the OP and IP.
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We have determined the electron-coupling spectrum of superconducting Bi2Sr2CaCu2O(8+δ) from high-resolution angle-resolved photoemission spectra by two deconvolution-free robust methods. As hole concentration decreases, the coupling spectral weight at low energies â²15 meV shows a twofold and nearly band-independent enhancement, while that around â¼65 meV increases moderately, and that in â³130 meV decreases leading to a crossover of dominant coupling excitation between them. Our results suggest the competition among multiple screening effects, and provide important clues to the source of sufficiently strong low-energy coupling, λ(LE)≈1, in an underdoped system.
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Aleukaemic leukaemia cutis is a rare condition characterized by infiltration of leukaemic cells into the skin before they appear in the peripheral blood. We report a case of an aleukaemic leukaemia cutis, which had a history of exposure to atomic bomb radiation. A 57-year-old Japanese woman initially presented with a 20-week history of multiple red papules and plaques mainly over the trunk. Histological examination revealed the infiltration of atypical monocytic cells in the dermis, but no leukaemic cells were detected in the peripheral blood. Twenty-three weeks after the appearance of the eruption, leukaemic cells were detected in the peripheral blood for the first time. The results of immunohistochemistry of the skin biopsy specimen and flow cytometry of the peripheral blood indicated the rare phenotype of myeloid/NK cell precursor acute leukaemia. This is the first case report of myeloid/NK cell precursor acute leukaemia presenting as aleukaemic leukaemia cutis in the English literature, and awareness of this clinical presentation may be important to reach the correct diagnosis.
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Células Asesinas Naturales/patología , Leucemia Mieloide/diagnóstico , Leucemia Inducida por Radiación/diagnóstico , Leucemia/diagnóstico , Resultado Fatal , Femenino , Humanos , Japón , Persona de Mediana EdadRESUMEN
We report a 73-year-old Japanese female who developed IgG autoantibodies against BP180 as well as desmoglein 3 (Dsg3). She showed tense blisters on the extremities without apparent mucosal involvement and a skin biopsy indicated subepidermal blisters with eosinophilic spongiosis. Her clinical and histologic features indicated the diagnosis of bullous pemphigoid while anti-Dsg3 IgG might not show an apparent pathogenic effect. Interestingly, titres of anti-Dsg3 IgG fluctuated in parallel with those of anti-BP180 IgG throughout the course with two flares. Although the exact mechanism for autoantibody production is still unknown, the close link in the production of IgG autoantibodies against two independent skin antigens suggests a shared immunoregulatory mechanism against cutaneous autoantigens.
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Autoanticuerpos/sangre , Autoantígenos/inmunología , Cadherinas/inmunología , Penfigoide Ampolloso/inmunología , Anciano , Desmogleína 3 , Femenino , Humanos , Inmunoglobulina G/sangre , Colágenos no Fibrilares , Penfigoide Ampolloso/patología , Colágeno Tipo XVIIRESUMEN
The mechanism of the suppressive effect of nonsteroidal anti-inflammatory drugs in azoxymethan and dextran sulfate sodium-induced colonic aberrant crypt foci/tumors associated with chronic colitis in mice was studied. With administration of sulindac, a cyclooxygenase-1 and -2 inhibitor, the mean number of colonic aberrant crypt foci/tumors was significantly smaller than that of controls. There was no significant difference in prostaglandin E2 content in the colonic mucosa between the groups. Furthermore, nimesulid, a cyclooxygenase-2 selective inhibitor, also suppressed colonic aberrant crypt foci/tumors as well as sulindac. Administration of nimesulid caused apoptosis indices to be significantly higher along with cyclooxygenase-2 expression being significantly lower than in controls. Apoptosis indices of 400 ppm group of nimesulid were significantly higher than that of 200 ppm group. Nonsteroidal anti-inflammatory drugs distinctly suppress the occurrence of aberrant crypt foci/tumors in this murine colitis-associated neoplasia model. Induction of apoptosis is a more important factor for chemoprevention than this reduction of prostaglandin E2.
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Quimioprevención/métodos , Colitis/prevención & control , Neoplasias del Colon/prevención & control , Neoplasias Colorrectales/prevención & control , Inhibidores de la Ciclooxigenasa/uso terapéutico , Sulindac/uso terapéutico , Animales , Apoptosis , Azoximetano , Carcinógenos , Enfermedad Crónica , Colitis/complicaciones , Colon/citología , Colon/efectos de los fármacos , Colon/patología , Neoplasias del Colon/inducido químicamente , Inhibidores de la Ciclooxigenasa/administración & dosificación , Mucosa Intestinal/citología , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/patología , Masculino , Ratones , Ratones Endogámicos CBA , Sulindac/administración & dosificación , Abastecimiento de AguaRESUMEN
We describe a case of isolated right ventricular infarction that has rarely been diagnosed antemortem. Electrocardiogram showed ST segment elevation in left precordial chest, right precordial chest, and inferior leads, which mimicked those of anterior and inferior left ventricular infarction. Coronary angiography revealed that culprit lesion was totally occluded right coronary artery. Infarcted artery was nondominant right coronary artery with branches supplying only right ventricular wall. Restoration of coronary blood flow was obtained by primary stenting and resulted in prompt ST segment normalization in all leads. Despite extensive right ventricular wall motion abnormality, subsequent right ventricular dysfunction was not observed.