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1.
Phys Rev Lett ; 128(24): 247203, 2022 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-35776483

RESUMEN

A chiral spin soliton lattice (CSL), one of the representative systems of a magnetic superstructure, exhibits reconfigurability in periodicity over a macroscopic length scale. Such coherent and tunable characteristics of the CSL lead to an emergence of elementary excitation of the CSL as phononlike modes due to translational symmetry breaking and bring a controllability of the dispersion relation of the CSL phonon. Using a broadband microwave spectroscopy technique, we directly found that higher-order magnetic resonance modes appear in the CSL phase of a chiral helimagnet CrNb_{3}S_{6}, which is ascribed to the CSL phonon response. The resonance frequency of the CSL phonon can be tuned between 16 and 40 GHz in the vicinity of the critical field, where the CSL period alters rapidly. The frequency range of the CSL phonon is expected to extend over 100 GHz as extrapolated on the basis of the theoretical model. The present results indicate that chiral helimagnets could work as materials useful for broadband signal processing in the millimeter-wave band.

2.
Phys Rev Lett ; 122(1): 017204, 2019 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-31012683

RESUMEN

Using Lorentz transmission electron microscopy and small-angle electron scattering techniques, we investigate the temperature-dependent evolution of a magnetic stripe pattern period in thin-film lamellae of the prototype monoaxial chiral helimagnet CrNb_{3}S_{6}. The sinusoidal stripe pattern appears due to formation of a chiral helimagnetic order (CHM) in this material. We found that as the temperature increases, the CHM period is initially independent of temperature and then starts to shrink above the temperature of about 90 K, which is far below the magnetic phase transition temperature for the bulk material T_{c} (123 K). The stripe order disappears at around 140 K, far above T_{c}. We argue that this cascade of transitions reflects a three-stage hierarchical behavior of melting in two dimensions.

3.
Phys Rev Lett ; 120(13): 132505, 2018 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-29694189

RESUMEN

We report on the first observation of γ rays emitted from an sd-shell hypernucleus, _{Λ}^{19}F. The energy spacing between the ground state doublet, 1/2^{+} and 3/2^{+} states, of _{Λ}^{19}F is determined to be 315.5±0.4(stat)_{-0.5}^{+0.6}(syst) keV by measuring the γ-ray energy of the M1(3/2^{+}→1/2^{+}) transition. In addition, three γ-ray peaks are observed and assigned as E2(5/2^{+}→1/2^{+}), E1(1/2^{-}→1/2^{+}), and E1(1/2^{-}→3/2^{+}) transitions. The excitation energies of the 5/2^{+} and 1/2^{-} states are determined to be 895.2±0.3(stat)±0.5(syst) and 1265.6±1.2(stat)_{-0.5}^{+0.7}(syst) keV, respectively. It is found that the ground state doublet spacing is well described by theoretical models based on existing s- and p-shell hypernuclear data.

4.
Phys Rev Lett ; 120(11): 117201, 2018 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-29601740

RESUMEN

We demonstrate that light-induced heat pulses of different duration and energy can write Skyrmions in a broad range of temperatures and magnetic field in FeGe. Using a combination of camera-rate and pump-probe cryo-Lorentz transmission electron microscopy, we directly resolve the spatiotemporal evolution of the magnetization ensuing optical excitation. The Skyrmion lattice was found to maintain its structural properties during the laser-induced demagnetization, and its recovery to the initial state happened in the sub-µs to µs range, depending on the cooling rate of the system.

5.
Clin Exp Dermatol ; 43(2): 175-179, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29271496

RESUMEN

Pseudoxanthoma elasticum (PXE) is a disease characterized by aberrant mineralization of soft tissue and fragmentation of elastic fibres. It is often difficult to distinguish PXE clinically from pseudoxanthoma elasticum-like papillary dermal elastolysis (PXE-like PDE). However, we have identified that the dermoscopic findings in PXE include coalescing and reticulated yellow-white clods on a light purple-red background, whereas the dermoscopic findings in PXE-like PDE lack such a coloured background. To our knowledge, this is the first detailed description of dermoscopic differences between PXE and PXE-like PDE.


Asunto(s)
Dermis/patología , Tejido Elástico/patología , Seudoxantoma Elástico/diagnóstico , Anciano , Dermoscopía , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Seudoxantoma Elástico/patología , Piel/patología
6.
Sci Rep ; 7(1): 11064, 2017 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-28894134

RESUMEN

A technique is presented whereby the performance of a microwave device is evaluated by mapping local field distributions using Lorentz transmission electron microscopy (L-TEM). We demonstrate the method by measuring the polarisation state of the electromagnetic fields produced by a microstrip waveguide as a function of its gigahertz operating frequency. The forward and backward propagating electromagnetic fields produced by the waveguide, in a specimen-free experiment, exert Lorentz forces on the propagating electron beam. Importantly, in addition to the mapping of dynamic fields, this novel method allows detection of effects of microwave fields on specimens, such as observing ferromagnetic materials at resonance.

7.
Phys Rev Lett ; 117(8): 087202, 2016 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-27588877

RESUMEN

Theoretical analysis and Lorentz transmission electron microscopy (LTEM) investigations in an FeGe wedge demonstrate that chiral twists arising near the surfaces of noncentrosymmetric ferromagnets [Meynell et al., Phys. Rev. B 90, 014406 (2014)] provide a stabilization mechanism for magnetic Skyrmion lattices and helicoids in cubic helimagnet nanolayers. The magnetic phase diagram obtained for freestanding cubic helimagnet nanolayers shows that magnetization processes differ fundamentally from those in bulk cubic helimagnets and are characterized by the first-order transitions between modulated phases. LTEM investigations exhibit a series of hysteretic transformation processes among the modulated phases, which results in the formation of the multidomain patterns.

8.
Hernia ; 18(3): 407-11, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23644742

RESUMEN

BACKGROUND: Patients with incarcerated obturator hernia are usually elderly, frail, and physically inactive women with serious comorbidities. Although a laparotomy is standard surgical intervention for emergency incarcerated or strangulated obturator hernia, it is invasive particularly for these high-risk patients. The aim of this study is to show the feasibility of minimum open inguinal approach to reduce surgical risk for preoperatively diagnosed incarcerated obturator hernia. METHODS: Between April 2008 and July 2012, 3 consecutive incarcerated obturator hernia patients at Kamitsuga General Hospital who were diagnosed preoperatively by computed tomography underwent the following procedure. First a 4 cm inguinal hernia incision and preperitoneal dissection through the opening of the deep inguinal ring are made. The obturator hernia can be easily found 2 cm dorsally from the Cooper's ligament extraperitoneally. A small incision is made at medial sharp edge of the hernia defect. The hernia sac and its content can then be reduced. If the incarcerated bowel is viable, a prosthetic mesh is placed as a patch. If the bowel is necrotic, the damaged bowel loop is withdrawn through the wound and easily reconstructed extra-abdominally. RESULTS: All operations were successfully completed with this procedure. All patients recovered without incident. CONCLUSIONS: Minimal incision transinguinal repair for diagnosed incarcerated obturator hernia is feasible and provides an improved option to more invasive procedures.


Asunto(s)
Hernia Obturadora/cirugía , Herniorrafia/métodos , Anciano , Anciano de 80 o más Años , Femenino , Hernia Obturadora/complicaciones , Humanos , Obstrucción Intestinal/etiología , Obstrucción Intestinal/patología , Obstrucción Intestinal/cirugía , Intestinos/irrigación sanguínea , Procedimientos Quirúrgicos Mínimamente Invasivos , Mallas Quirúrgicas
9.
Phys Rev Lett ; 111(19): 197204, 2013 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-24266487

RESUMEN

We investigate the interlayer magnetoresistance (MR) along the chiral crystallographic axis in the hexagonal chiral magnet CrNb3S6. In a region below the incommensurate-commensurate phase transition between the chiral soliton lattice and the forced ferromagnetic state, a negative MR is obtained in a wide range of temperature, while a small positive MR is found very close to the Curie temperature. Normalized data of the negative MR almost falls into a single curve and is well fitted by a theoretical equation of the soliton density, meaning that the origin of the MR is ascribed to the magnetic scattering of conduction electrons by a nonlinear, periodic, and countable array of magnetic soliton kinks.

10.
Case Rep Dermatol Med ; 2012: 401362, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23259081

RESUMEN

We report the first case of 68-year-old Japanese woman with metastatic HER2-positive extramammary Paget's disease that showed the validity of trastuzumab monotherapy. We administered trastuzumab at a loading dose of 8 mg/kg i.v., followed by a 6 mg/kg maintenance dose every three weeks according to a protocol for HER2-positive metastatic breast cancers and a near-complete response was achieved after the tenth infusion. The patient experienced a moderate headache and flushing during the first infusion, but had no advanced effects during subsequent infusions with ibuprofen and d-chlorpheniramine maleate. Given the dramatic response, the patient has had 17 infusions of trastuzumab with no disease progression. Thus, trastuzumab has few side effects and is well tolerated for elderly patients. It may become a new choice of the adjubant therapy of this disease.

11.
Phys Rev Lett ; 108(10): 107202, 2012 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-22463448

RESUMEN

Using Lorenz microscopy and small-angle electron diffraction, we directly present that the chiral magnetic soliton lattice (CSL) continuously evolves from a chiral helimagnetic structure in small magnetic fields in Cr(1/3)NbS2. An incommensurate CSL undergoes a phase transition to a commensurate ferromagnetic state at the critical field strength. The period of a CSL, which exerts an effective potential for itinerant spins, is tuned by simply changing the field strength. Chiral magnetic orders observed do not exhibit any structural dislocation, indicating their high stability and robustness in Cr(1/3)NbS2.


Asunto(s)
Campos Magnéticos , Imanes/química , Compuestos de Cromo/química , Cristalización , Modelos Moleculares , Niobio/química , Dispersión del Ángulo Pequeño , Estereoisomerismo , Sulfuros/química , Difracción de Rayos X
12.
Int J Dermatol ; 49(12): 1362-7, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21155082

RESUMEN

BACKGROUND: Malignant melanomas clinically and/or histologically associated with melanocytic nevi have been reported worldwide. Approximately 20% of malignant melanomas in Caucasians, most of which are found on the trunk and proximal extremities, develop in association with pre-existing melanocytic nevi. In Japan, however, over half of all melanomas are acral lentiginous melanomas (ALMs) on the hands and feet; melanomas on sun-exposed areas are seen less frequently in Japanese people than in Caucasians. As ALMs are not usually accompanied by melanocytic nevi and there have been no reviews of the literature or statistical data regarding Japanese cases of melanomas with melanocytic nevi, dermatologists in Japan have few opportunities to see melanomas associated with pre-existing melanocytic nevi. METHODS: Here we report a case of a superficial spreading melanoma that was formed on a melanocytic nevus on the trunk, and we review for the first time the case reports from the Japanese literature. RESULTS AND CONCLUSIONS: With regard to the reported cases, melanomas associated with melanocytic nevi were mainly superficial spreading melanomas and nodular melanomas on the trunk or extremities; ALMs were rarely associated with nevi, indicating a trend similar to that observed in Caucasians. These findings suggest that the low frequency of associations between melanomas and melanocytic nevi in Japan reflects racial differences in the frequencies of each type of melanoma.


Asunto(s)
Melanoma/complicaciones , Melanoma/patología , Nevo Pigmentado/complicaciones , Neoplasias Cutáneas/complicaciones , Neoplasias Cutáneas/patología , Adulto , Anciano de 80 o más Años , Femenino , Humanos , Japón , Masculino , Melanoma/cirugía , Persona de Mediana Edad , Neoplasias Cutáneas/cirugía
14.
Clin Exp Dermatol ; 29(1): 71-3, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14723727

RESUMEN

A patient had triple extramammary Paget's disease of both axillary and genital regions. Right inguinal lymphadenopathy was found 1 year after excision of all the skin lesions. Excisional biopsy of the lymph node demonstrated a mixture of Paget cells and atypical squamoid cells with horn pearls suggestive of keratinization. The squamoid cells were positive for cytokeratin 10, a marker of suprabasal epidermis, and also positive for laminin gamma2 which is often expressed in invasive squamous cell carcinoma. The coexistence of these different cells within the same tumour island suggested that the squamoid cells derived from metaplasia of Paget cells.


Asunto(s)
Neoplasias de los Genitales Masculinos/patología , Enfermedad de Paget Extramamaria/patología , Escroto/patología , Anciano , Axila , Carcinoma de Células Escamosas/patología , Diagnóstico Diferencial , Humanos , Metástasis Linfática/patología , Masculino , Metaplasia/patología
16.
Genome Res ; 10(11): 1757-71, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11076861

RESUMEN

The RIKEN high-throughput 384-format sequencing pipeline (RISA system) including a 384-multicapillary sequencer (the so-called RISA sequencer) was developed for the RIKEN mouse encyclopedia project. The RISA system consists of colony picking, template preparation, sequencing reaction, and the sequencing process. A novel high-throughput 384-format capillary sequencer system (RISA sequencer system) was developed for the sequencing process. This system consists of a 384-multicapillary auto sequencer (RISA sequencer), a 384-multicapillary array assembler (CAS), and a 384-multicapillary casting device. The RISA sequencer can simultaneously analyze 384 independent sequencing products. The optical system is a scanning system chosen after careful comparison with an image detection system for the simultaneous detection of the 384-capillary array. This scanning system can be used with any fluorescent-labeled sequencing reaction (chain termination reaction), including transcriptional sequencing based on RNA polymerase, which was originally developed by us, and cycle sequencing based on thermostable DNA polymerase. For long-read sequencing, 380 out of 384 sequences (99.2%) were successfully analyzed and the average read length, with more than 99% accuracy, was 654.4 bp. A single RISA sequencer can analyze 216 kb with >99% accuracy in 2.7 h (90 kb/h). For short-read sequencing to cluster the 3' end and 5' end sequencing by reading 350 bp, 384 samples can be analyzed in 1.5 h. We have also developed a RISA inoculator, RISA filtrator and densitometer, RISA plasmid preparator which can handle throughput of 40,000 samples in 17.5 h, and a high-throughput RISA thermal cycler which has four 384-well sites. The combination of these technologies allowed us to construct the RISA system consisting of 16 RISA sequencers, which can process 50,000 DNA samples per day. One haploid genome shotgun sequence of a higher organism, such as human, mouse, rat, domestic animals, and plants, can be revealed by seven RISA systems within one month.


Asunto(s)
Electroforesis Capilar/instrumentación , Electroforesis Capilar/métodos , Genoma , Análisis de Secuencia de ADN/instrumentación , Análisis de Secuencia de ADN/métodos , Animales , Secuencia de Bases , ADN/análisis , Electroforesis Capilar/economía , Electroforesis Capilar/normas , Electroforesis en Gel de Poliacrilamida/economía , Electroforesis en Gel de Poliacrilamida/instrumentación , Electroforesis en Gel de Poliacrilamida/métodos , Electroforesis en Gel de Poliacrilamida/normas , Citometría de Imagen/economía , Citometría de Imagen/instrumentación , Citometría de Imagen/métodos , Citometría de Imagen/normas , Ratones , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa/economía , Reacción en Cadena de la Polimerasa/instrumentación , Reacción en Cadena de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa/normas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Análisis de Secuencia de ADN/economía , Análisis de Secuencia de ADN/normas , Moldes Genéticos
17.
Phys Rev Lett ; 85(17): 3716-9, 2000 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-11030989

RESUMEN

We studied the conduction noise spectrum in the vortex state of a high-temperature superconductor, Bi(2)Sr(2)CaCu(2)O(y), subject to a uniform driving force. Two characteristic features, a broad-band noise (BBN) and a narrow-band noise (NBN), were observed in the vortex-solid phase. The origin of the large BBN was determined to be plastic motion of the vortices, whereas the NBN was found to originate from the washboard modulation of the translational velocity of the driven vortices. We believe this to be the first observation of washboard noise of dc driven vortices in any superconductor.

18.
Bone Miner ; 27(3): 173-82, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7696885

RESUMEN

A modified and improved radiographic absorptiometry of the distal radius which enables on-site analysis, called computer assisted X-ray densitometry (CXD), was evaluated from the viewpoint of quality assessment. Its precision and the correlation with dual energy X-ray absorptiometry (DXA) was evaluated in 12 volunteers (mean age 44.7 years). The profile of CXD-measured radial bone mineral density (RBMD) from 142 subjects (75 premenopausal and 67 postmenopausal women, mean ages 44.9 and 50.6 years, respectively) were compared with previous data by other methodologies of bone mineral analysis. The intra-assay coefficient of variation (CV) was 0.617%, the inter-assay CV was 2.064%, and the inter-observer CV was 0.673%. The correlation between CXD-measured RBMD and DXA-measured RBMD was of statistical significance (r2 = 0.733, P < 0.01). The correlation of CXD-measured RBMD with age, height or weight corresponded well with previous reports. CXD-measured RBMD and DXA-measured vertebral bone mineral density (VBMD) also had a significant positive correlation, but their correlation was not so close (r2 = 0.149, P < 0.01). The discriminative ability of osteoporosis by CXD was of acceptable level (odd's ratio = 5.72, P < 0.05), when assessed by comparison with bone dystrophy score (BDS) on the plain vertebral radiogram. Although some problems remain in technical standardization, CXD could be an easy, inexpensive, and widely applicable alternative of non-weight bearing cancellous bone densitometry.


Asunto(s)
Absorciometría de Fotón/métodos , Densidad Ósea , Radio (Anatomía)/diagnóstico por imagen , Absorciometría de Fotón/estadística & datos numéricos , Adulto , Envejecimiento , Estatura , Peso Corporal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis Posmenopáusica/diagnóstico por imagen , Posmenopausia , Premenopausia , Sensibilidad y Especificidad
19.
J Clin Ultrasound ; 21(1): 9-17, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8386730

RESUMEN

The purpose of this article was to investigate the detection rate of gastroduodenal artery blood flow (GDABF), and to measure its velocity and volume flow rate using Doppler color imaging. The GDABF was detected in 40 of 41 (98%) normal subjects with longitudinal scanning and in 36 (88%) with transverse scanning. The velocity of the GDABF was 21 +/- 8 cm/sec (m +/- SD) and the volume flow rate was 67 +/- 20 mL/min. Without color Doppler, the vascular lumina of the GDA was demonstrated in 27 (66%) subjects by longitudinal scanning and in 26 (63%) by transverse scanning. The hemodynamics of the GDA were revealed noninvasively using Doppler ultrasonography in a patient with a malignant islet cell tumor of the pancreas and one with a ductal cell carcinoma of the pancreas.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Adenoma de Células de los Islotes Pancreáticos/diagnóstico por imagen , Duodeno/irrigación sanguínea , Duodeno/diagnóstico por imagen , Neoplasias Pancreáticas/diagnóstico por imagen , Estómago/irrigación sanguínea , Estómago/diagnóstico por imagen , Adenocarcinoma/fisiopatología , Adenoma de Células de los Islotes Pancreáticos/fisiopatología , Adolescente , Adulto , Anciano , Arterias/diagnóstico por imagen , Arterias/fisiología , Velocidad del Flujo Sanguíneo , Color , Duodeno/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/fisiopatología , Flujo Sanguíneo Regional , Estómago/fisiología , Ultrasonografía/métodos
20.
J Microencapsul ; 9(3): 329-33, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1403483

RESUMEN

Permeation of electrolyte ions through poly(L-lysine-alt-terephthalic acid) microcapsule membranes was studied as a function of the pH of the medium at different ionic strengths. When the pH of the medium was varied, the permeation rate for 5-sulphosalicylate anions, as well as phenyltrimethylammonium cations, was slow at pH values lower than 4, showed a sudden and large increase in the pH range between 4 and 6, and thereafter remained unchanged. This remarkable change in the permeation rate was found to be produced by an abrupt increase in the microcapsule size observed in the same pH range. Increase in the ionic strength of the medium at pH values higher than 6 increased the rate of anion permeation but decreased the rate of cation permeation due to increase in the screening effect of salt ions on the negative charges in the microcapsule membranes.


Asunto(s)
Cápsulas , Ácidos Ftálicos , Polilisina/análogos & derivados , Electrólitos , Concentración de Iones de Hidrógeno , Concentración Osmolar , Permeabilidad
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