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1.
Nanotechnology ; 31(26): 265606, 2020 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-32155610

RESUMEN

We report the elongation of embedded Au nanoparticles (NPs) in three different matrices, i.e. amorphous carbon (a-C), crystalline indium tin oxide (InxSn1-xOz; ITO) and crystalline calcium fluoride (CaF2), under irradiations of 4 MeV C60 + cluster ions and 200 MeV Xe14+ ions. Under 4 MeV C60 cluster irradiation, strong sputtering is induced in CaF2 layer so that the whole the layer was completely lost at a fluence of 5 × 1013 ions cm-2. Au NPs were partly observed in the SiO2, probably due to the recoil implantation. Amorphous carbon (a-C) layer exhibits low sputtering loss even under 4 MeV C60 irradiation. However, the elongation in a-C layer was low. While the ITO layer showed a certain decrease in thickness under 4 MeV C60 irradiation, large elongation of Au NPs was observed under both 4 MeV C60 and 200 MeV Xe irradiation. The ITO layer preserved the crystallinity even after large elongation was induced. This is the first report of the elongation of metal NPs in a crystalline matrix.

2.
Br J Anaesth ; 122(1): 150, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30579394

RESUMEN

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief of British Journal of Anaesthesia. The study is retracted for the following reasons: Statistical analysis suggests that the data may be fabricated. Y Saitoh provided a statement in a personal communication to a member of the editorial board of British Journal of Anaesthesia that the study was not approved by the Institutional Review Board and that no evidence exists to support the study findings. Additionally, the Japanese Society of Anesthesiologists has recommended retraction of this article: http://www.anesth.or.jp/english/pdf/news20170925.pdf.

3.
Br J Anaesth ; 122(1): 151, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30579395

RESUMEN

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief of British Journal of Anaesthesia. The study is retracted for the following reasons: Y Saitoh provided a statement in a personal communication to a member of the editorial board of British Journal of Anaesthesia that the study was not approved by the Institutional Review Board and that no evidence exists to support the study findings.

4.
Br J Anaesth ; 122(1): 154, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30579398

RESUMEN

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief of British Journal of Anaesthesia. The study is retracted for the following reasons: Statistical analysis suggests that the data may be fabricated. Y Saitoh provided a statement in a personal communication to a member of the editorial board of British Journal of Anaesthesia that the study was not approved by the Institutional Review Board and that no evidence exists to support the study findings.

5.
Br J Anaesth ; 122(1): 152, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30579396

RESUMEN

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief of British Journal of Anaesthesia. The study is retracted for the following reasons: Y Saitoh provided a statement in a personal communication to a member of the editorial board of British Journal of Anaesthesia that the study was not approved by the Institutional Review Board and that no evidence exists to support the study findings.

6.
Br J Anaesth ; 122(1): 153, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30579397

RESUMEN

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief of British Journal of Anaesthesia. The study is retracted for the following reasons: Y Saitoh provided a statement in a personal communication to a member of the editorial board of British Journal of Anaesthesia that the study was not approved by the Institutional Review Board and that no evidence exists to support the study findings.

7.
Br J Anaesth ; 122(1): 155, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30579399

RESUMEN

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief of British Journal of Anaesthesia. The study is retracted for the following reasons: Statistical analysis suggests that the data may be fabricated. Y Saitoh provided a statement in a personal communication to a member of the editorial board of British Journal of Anaesthesia that the study was not approved by the Institutional Review Board and that no evidence exists to support the study findings.

8.
Br J Anaesth ; 122(1): 156, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30579400

RESUMEN

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief of British Journal of Anaesthesia. The study is retracted for the following reasons: Statistical analysis suggests that the data may be fabricated. Y Saitoh provided a statement in a personal communication to a member of the editorial board of British Journal of Anaesthesia that the study was not approved by the Institutional Review Board and that no evidence exists to support the study findings. Additionally, the Japanese Society of Anesthesiologists has recommended retraction of this article: http://www.anesth.or.jp/english/pdf/news20170925.pdf.

9.
J Chem Phys ; 145(23): 234311, 2016 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-28010077

RESUMEN

We report probability distributions of the number of secondary ions (SIs) emitted by sub-MeV C60 ion impacts on an organic polymer target and the characterization of their emission processes through the analysis of the distributions. The probability distributions were obtained by analyzing experimental SI counting data obtained by a time-of-flight SI mass spectrometer combined with pulsed primary ion beams, using an analytical model developed to derive the distributions from the experimental data. A series of probability distribution functions was investigated for ion impacts of C60 with sub-MeV energies (0.12-0.54 MeV), which can provide sufficient SIs per impact to determine the functions. Their complicated and undefined SI emission processes were characterized based on the determined functions.

10.
Biochem Biophys Res Commun ; 443(4): 1176-81, 2014 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-24406164

RESUMEN

Human induced pluripotent stem cell (hiPSC)-derived neurons may be effectively used for drug discovery and cell-based therapy. However, the immaturity of cultured human iPSC-derived neurons and the lack of established functional evaluation methods are problematic. We here used a multi-electrode array (MEA) system to investigate the effects of the co-culture of rat astrocytes with hiPSC-derived neurons on the long-term culture, spontaneous firing activity, and drug responsiveness effects. The co-culture facilitated the long-term culture of hiPSC-derived neurons for >3 months and long-term spontaneous firing activity was also observed. After >3 months of culture, we observed synchronous burst firing activity due to synapse transmission within neuronal networks. Compared with rat neurons, hiPSC-derived neurons required longer time to mature functionally. Furthermore, addition of the synapse antagonists bicuculline and 6-cyano-7-nitroquinoxaline-2,3-dione induced significant changes in the firing rate. In conclusion, we used a MEA system to demonstrate that the co-culture of hiPSC-derived neurons with rat astrocytes is an effective method for studying the function of human neuronal cells, which could be used for drug screening.


Asunto(s)
Astrocitos/efectos de los fármacos , Astrocitos/fisiología , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Células Madre Pluripotentes Inducidas/fisiología , Neuronas/efectos de los fármacos , Neuronas/fisiología , 6-Ciano 7-nitroquinoxalina 2,3-diona/farmacología , Potenciales de Acción/efectos de los fármacos , Animales , Astrocitos/citología , Bicuculina/farmacología , Diferenciación Celular , Técnicas de Cocultivo , Evaluación Preclínica de Medicamentos , Fenómenos Electrofisiológicos , Humanos , Células Madre Pluripotentes Inducidas/citología , Red Nerviosa/citología , Red Nerviosa/efectos de los fármacos , Red Nerviosa/fisiología , Neuronas/citología , Neurotransmisores/farmacología , Ratas , Transmisión Sináptica
11.
Nat Commun ; 15(1): 1786, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38413643

RESUMEN

Injecting high-energy heavy ions in the electronic stopping regime into solids can create cylindrical damage zones called latent ion tracks. Although these tracks form in many materials, none have ever been observed in diamond, even when irradiated with high-energy GeV uranium ions. Here we report the first observation of ion track formation in diamond irradiated with 2-9 MeV C60 fullerene ions. Depending on the ion energy, the mean track length (diameter) changed from 17 (3.2) nm to 52 (7.1) nm. High resolution scanning transmission electron microscopy (HR-STEM) indicated the amorphization in the tracks, in which π-bonding signal from graphite was detected by the electron energy loss spectroscopy (EELS). Since the melting transition is not induced in diamond at atmospheric pressure, conventional inelastic thermal spike calculations cannot be applied. Two-temperature molecular dynamics simulations succeeded in the reproduction of both the track formation under MeV C60 irradiations and the no-track formation under GeV monoatomic ion irradiations.

12.
Phys Rev Lett ; 110(24): 247601, 2013 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-25165961

RESUMEN

The interface between LaAlO(3) and SrTiO(3) hosts a two-dimensional electron system of itinerant carriers, although both oxides are band insulators. Interface ferromagnetism coexisting with superconductivity has been found and attributed to local moments. Experimentally, it has been established that Ti 3d electrons are confined to the interface. Using soft x-ray angle-resolved resonant photoelectron spectroscopy we have directly mapped the interface states in k space. Our data demonstrate a charge dichotomy. A mobile fraction contributes to Fermi surface sheets, whereas a localized portion at higher binding energies is tentatively attributed to electrons trapped by O vacancies in the SrTiO(3). While photovoltage effects in the polar LaAlO(3) layers cannot be excluded, the apparent absence of surface-related Fermi surface sheets could also be fully reconciled in a recently proposed electronic reconstruction picture where the built-in potential in the LaAlO(3) is compensated by surface O vacancies serving also as a charge reservoir.

13.
J Synchrotron Radiat ; 19(Pt 2): 223-6, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22338683

RESUMEN

FeRh thin films were irradiated with a 10 MeV iodine ion microbeam to produce micrometre-scale ferromagnetic microstructures by modifying the local magnetic character from antiferromagnetism to ferromagnetism using ion-microbeam irradiation. Two-dimensional magnetic dot arrays of dimensions ∼2 µm × 4 µm as well as 10 µm × 10 µm were successfully produced on the FeRh surface, which was confirmed by magnetic force microscopy (MFM). The results of photoemission electron microscopy (PEEM) combined with X-ray magnetic circular dichroism reveal that the easy axis of the magnetization of the ion-beam-irradiated ferromagnetism in the FeRh thin films lies in the film planes along the <001> direction of the MgO substrates.

14.
Microsc Microanal ; 18(5): 1030-6, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23058452

RESUMEN

Adenosine triphosphate (ATP) is a well-known energy source for muscle contraction. In this study, to visualize localization of ATP, a luciferin-luciferase reaction (LLR) was performed in mouse skeletal muscle with an "in vivo cryotechnique" (IVCT). First, to confirm if ATP molecules could be trapped and detected after glutaraldehyde (GA) treatment, ATP was directly attached to glass slides with GA, and LLR was performed. The LLR was clearly detected as an intentional design of the ATP attachment. The intensity of the light unit by LLR was correlated with the concentration of the GA-treated ATP in vitro. Next, LLR was evaluated in mouse skeletal muscles with IVCT followed by freeze-substitution fixation (FS) in acetone-containing GA. In such tissue sections the histological structure was well maintained, and the intensity of LLR in areas between muscle fibers and connective tissues was different. Moreover, differences in LLR among muscle fibers were also detected. For the IVCT-FS tissue sections, diaminobenzidine (DAB) reactions were clearly detected in type I muscle fibers and erythrocytes in capillaries, which demonstrated flow shape. Thus, it became possible to perform microscopic evaluation of the numbers of ATP molecules in the mouse skeletal muscles with IVCT, which mostly reflect living states.


Asunto(s)
Adenosina Trifosfato/análisis , Luciferina de Luciérnaga/metabolismo , Substitución por Congelación/métodos , Luciferasas/metabolismo , Músculo Esquelético/química , Adenosina Trifosfato/metabolismo , Animales , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Músculo Esquelético/citología , Músculo Esquelético/metabolismo
15.
J Small Anim Pract ; 63(9): 699-706, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35577348

RESUMEN

OBJECTIVES: To describe the diagnostic findings, surgical technique and outcomes in seven pugs with thoracolumbar vertebral instability due to articular process anomalies. MATERIALS AND METHODS: Records (2010 to 2019) of pugs with thoracolumbar vertebral instability associated with articular process anomalies that underwent decompressive laminectomy and vertebral stabilisation were reviewed. Data on preoperative and postoperative neurologic status, diagnostic findings, surgical techniques and outcomes were retrieved. RESULTS: Seven dogs were presented with ambulatory or non-ambulatory paraparesis. Caudal articular process anomalies (three dogs) and concomitant cranial and caudal articular process anomalies (four dogs) were noted. Myelography (six dogs) or magnetic resonance imaging (one dog) showed none to severe spinal cord compression. Dynamic myelography in six dogs demonstrated nine distinct sites of spinal cord dimension reduction positioned in extension and/or flexion (mean reduction: 16.0%, range: 8.5 to 24.0%). These dynamic compressions were located at sites with articular process anomalies (seven sites) and sites with no articular process anomalies (two sites). Vertebral instability was confirmed by intraoperative spinal manipulation in all dogs. All dogs remained ambulatory with improved (five dogs) or static (two dogs) neurological deficits at the last follow-up (median: 16 months; range: 1.5 to 66 months). CLINICAL SIGNIFICANCE: Dynamic myelography and/or intraoperative spinal manipulation demonstrated vertebral instabilities at sites with or without articular process anomalies on imaging. Decompressive laminectomy with vertebral stabilisation resulted in long-term neurological improvement in most dogs.


Asunto(s)
Enfermedades de los Perros , Compresión de la Médula Espinal , Animales , Enfermedades de los Perros/diagnóstico por imagen , Enfermedades de los Perros/cirugía , Perros , Vértebras Lumbares , Imagen por Resonancia Magnética/veterinaria , Compresión de la Médula Espinal/diagnóstico por imagen , Compresión de la Médula Espinal/cirugía , Compresión de la Médula Espinal/veterinaria , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/cirugía
16.
Endoscopy ; 43(10): 862-8, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21732270

RESUMEN

BACKGROUND AND STUDY AIMS: Conventional colonoscopy can result in unnecessary biopsy or endoscopic resection due to its inability to distinguish adenomas from hyperplastic polyps. This study therefore evaluated the efficacy of high-resolution endoscopy (HRE), autofluorescence imaging (AFI), and narrow-band imaging (NBI) in discriminating colon adenoma from hyperplastic polyps. PATIENTS AND METHODS: This was a prospective multicenter study in patients undergoing AFI and NBI examinations. HRE, AFI, and NBI images were classified into two groups based on morphological characteristics, the predominant color intensities, and the visibility of meshed capillary vessels, respectively. Each of the endoscopic photographs were independently evaluated by a single endoscopist. The images were then assessed by three specialists and three residents, the latter having performed < 500 colonoscopies and < 30 NBI and AFI examinations. Diagnostic test statistics were calculated to compare the accuracy in differentiating colon adenoma from hyperplastic polyps for each method. RESULTS: A total of 183 patients were enrolled in the study and 339 adenomas and 85 hyperplastic polyps were identified. AFI and NBI could distinguish adenoma from hyperplastic polyps with an accuracy of 84.9 % and 88.4 %, respectively, whereas HRE exhibited an accuracy of 75.9 %. In the 358 lesions in which the AFI diagnosis was consistent with that of NBI, the accuracy, sensitivity, and specificity were high, at 91.9 %, 92.7 %, and 92.9 %, respectively. During the study comparing specialists and residents, AFI and NBI dramatically improved the diagnostic accuracy of residents from 69.1 % to 86.1 % and 84.7 %, respectively. CONCLUSIONS: Both AFI and NBI are considered to be feasible tools that can discriminate colon adenoma from hyperplastic polyps, and their use may be particularly beneficial for less-experienced endoscopists.


Asunto(s)
Adenoma/diagnóstico , Neoplasias del Colon/diagnóstico , Pólipos del Colon/diagnóstico , Colonoscopía/métodos , Aumento de la Imagen/métodos , Anciano , Diagnóstico Diferencial , Femenino , Fluorescencia , Humanos , Luz , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Sensibilidad y Especificidad , Estadísticas no Paramétricas
17.
Thorac Cardiovasc Surg ; 59(6): 378-80, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21766279

RESUMEN

We report a case of a 54-year-old man with T4N0M0 non-small cell lung cancer directly invading the thoracic wall and aortic arch. He underwent neoadjuvant chemotherapy followed by en bloc resection of the tumor, lung, chest wall and aortic arch. Perfusion was maintained through femoral-femoral cardiopulmonary bypass, with permanent bypass to the arch vessels to avoid separate extracorporeal cerebral circulation. Total reconstructions of the chest wall and aortic arch were completed without the need for cardiac arrest. The final pathological diagnosis was squamous cell carcinoma, T4N0M0. The patient was discharged without major complications and has been free of disease for 20 months postoperatively.


Asunto(s)
Aorta Torácica/cirugía , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Carcinoma de Células Escamosas/cirugía , Circulación Cerebrovascular , Neoplasias Pulmonares/cirugía , Perfusión/métodos , Neumonectomía , Procedimientos Quirúrgicos Vasculares , Aorta Torácica/diagnóstico por imagen , Aorta Torácica/patología , Aorta Torácica/fisiopatología , Aortografía/métodos , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/fisiopatología , Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/fisiopatología , Quimioterapia Adyuvante , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/fisiopatología , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Invasividad Neoplásica , Estadificación de Neoplasias , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
18.
Kyobu Geka ; 64(5): 379-82, 2011 May.
Artículo en Japonés | MEDLINE | ID: mdl-21591438

RESUMEN

Cardiac reoperation via a median re-sternotomy is associated with a high risk of injury to cardiac structures and the great vessels, and may result in massive bleeding. We report a case of aortic valve re-replacement, and severe adhesion was suspected between the sternum and the left brachiocephalic vein by preoperative computed tomography (CT) scans. To avoid injury to the vein, the adhesive tissue was dissected under video-assisted thoracic surgery (VATS). Then median re-sternotomy was performed safely, and the aortic valve was replaced again. The patient's postoperative course was uneventful. Since sternal adhesions are checked and dissected visually, concomitant VATS might be a very useful option after previous cardiac surgery.


Asunto(s)
Válvula Aórtica , Implantación de Prótesis de Válvulas Cardíacas/métodos , Esternotomía/métodos , Cirugía Torácica Asistida por Video , Anciano , Femenino , Humanos , Reoperación
19.
Sci Rep ; 11(1): 185, 2021 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-33420182

RESUMEN

Damaged regions of cylindrical shapes called ion tracks, typically in nano-meters wide and tens micro-meters long, are formed along the ion trajectories in many insulators, when high energy ions in the electronic stopping regime are injected. In most cases, the ion tracks were assumed as consequences of dense electronic energy deposition from the high energy ions, except some cases where the synergy effect with the nuclear energy deposition plays an important role. In crystalline Si (c-Si), no tracks have been observed with any monomer ions up to GeV. Tracks are formed in c-Si under 40 MeV fullerene (C60) cluster ion irradiation, which provides much higher energy deposition than monomer ions. The track diameter decreases with decreasing the ion energy until they disappear at an extrapolated value of ~ 17 MeV. However, here we report the track formation of 10 nm in diameter under C60 ion irradiation of 6 MeV, i.e., much lower than the extrapolated threshold. The diameters of 10 nm were comparable to those under 40 MeV C60 irradiation. Furthermore, the tracks formed by 6 MeV C60 irradiation consisted of damaged crystalline, while those formed by 40 MeV C60 irradiation were amorphous. The track formation was observed down to 1 MeV and probably lower with decreasing the track diameters. The track lengths were much shorter than those expected from the drop of Se below the threshold. These track formations at such low energies cannot be explained by the conventional purely electronic energy deposition mechanism, indicating another origin, e.g., the synergy effect between the electronic and nuclear energy depositions, or dual transitions of transient melting and boiling.

20.
Sci Rep ; 11(1): 18654, 2021 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34545160

RESUMEN

Band-gap engineering is one of the fundamental techniques in semiconductor technology and also applicable in next generation spintronics using the spin degree of freedom. To fully utilize the spintronic materials, it is essential to optimize the spin-dependent electronic structures in the operando conditions by applying magnetic and/or electric fields. Here we present an advanced spectroscopic technique to probe the spin-polarized electronic structures by using magnetic circular dichroism (MCD) in resonant inelastic soft X-ray scattering (RIXS) under an external magnetic field. Thanks to the spin-selective dipole-allowed transitions in RIXS-MCD, we have successfully demonstrated the direct evidence of the perfectly spin-polarized electronic structures for the prototypical halfmetallic Heusller alloy [Formula: see text]. RIXS-MCD is a promising tool to probe the spin-dependent carriers and band-gap induced in the buried magnetic layers in an element specific way under the operando conditions.

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