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1.
Phys Rev Lett ; 125(2): 027201, 2020 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-32701305

RESUMEN

We measure the mode-resolved direction of the precessional motion of the magnetic order, i.e., magnon polarization, via the chiral term of inelastic polarized neutron scattering spectra. The magnon polarization is a unique and unambiguous signature of magnets and is important in spintronics, affecting thermodynamic properties such as the magnitude and sign of the spin Seebeck effect. However, it has never been directly measured in any material until this work. The observation of both signs of magnon polarization in Y_{3}Fe_{5}O_{12} also gives direct proof of its ferrimagnetic nature. The experiments agree very well with atomistic simulations of the scattering cross section.

2.
Clin Exp Allergy ; 48(5): 577-585, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29368358

RESUMEN

BACKGROUND: Environmental factors seem to be related to the incidence of allergic disease. Children with a later birth order are often exposed to environments, where pathogens and endotoxins can be found, and thus have a higher risk of developing infectious diseases. Therefore, birth order is regarded as an indicator that reflects post-natal environment. However, longitudinal studies are limited on this subject. This study sought to elucidate the relationships between birth order and allergic disease. METHODS: From a nationwide longitudinal study that followed children born in 2001 (n = 47 015), we selected doctors' visits for 3 types of allergic disease-bronchial asthma, food allergy and atopic dermatitis-from infancy to 12 years of age and conducted binomial log-linear regression analysis to evaluate the associations between birth order and these diseases. We adjusted for the child and parental factors and estimated risk ratio (RR) and 95% confidence interval (CI) for each outcome. RESULTS: The associations between birth order and bronchial asthma were diverse; later birth order increased the risk in early childhood, but decreased the risks during school age. For example, the adjusted RR comparing third-born or higher and first-born children was 1.19 (95% CI, 1.05-1.35) between 30 and 42 months of age, but was 0.76 (95% CI, 0.65-0.89) between 10 and 11 years. Later birth order was generally protective for food allergy but increased the risk of atopic dermatitis. CONCLUSION: The influence of birth order depended on the type of allergic disease and the childhood period. Childhood is unique in terms of physical and immunological development, and the immune response to the post-natal environment in childhood appears to be heterogeneous.


Asunto(s)
Orden de Nacimiento , Hipersensibilidad/epidemiología , Niño , Preescolar , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Japón/epidemiología , Estudios Longitudinales , Masculino , Encuestas y Cuestionarios
3.
Phys Rev Lett ; 110(6): 067207, 2013 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-23432302

RESUMEN

This Letter provides evidence for intrinsic longitudinal spin Seebeck effects (LSSEs) that are free from the anomalous Nernst effect (ANE) caused by an extrinsic proximity effect. We report the observation of LSSEs in Au/Y(3)Fe(5)O(12) (YIG) and Pt/Cu/YIG systems, showing that the LSSE appears even when the mechanism of the proximity ANE is clearly removed. In the conventional Pt/YIG structure, furthermore, we separate the LSSE from the ANE by comparing the voltages in different magnetization and temperature-gradient configurations; the ANE contamination was found to be negligibly small even in the Pt/YIG structure.

4.
Nat Commun ; 14(1): 1818, 2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-37002246

RESUMEN

Antiferromagnetic materials have been proposed as new types of narrowband THz spintronic devices owing to their ultrafast spin dynamics. Manipulating coherently their spin dynamics, however, remains a key challenge that is envisioned to be accomplished by spin-orbit torques or direct optical excitations. Here, we demonstrate the combined generation of broadband THz (incoherent) magnons and narrowband (coherent) magnons at 1 THz in low damping thin films of NiO/Pt. We evidence, experimentally and through modeling, two excitation processes of spin dynamics in NiO: an off-resonant instantaneous optical spin torque in (111) oriented films and a strain-wave-induced THz torque induced by ultrafast Pt excitation in (001) oriented films. Both phenomena lead to the emission of a THz signal through the inverse spin Hall effect in the adjacent heavy metal layer. We unravel the characteristic timescales of the two excitation processes found to be < 50 fs and > 300 fs, respectively, and thus open new routes towards the development of fast opto-spintronic devices based on antiferromagnetic materials.

5.
Eur Surg Res ; 47(1): 32-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21576972

RESUMEN

BACKGROUND: Glucose control is essential to avoid hypoglycemia in postoperative patients. AIM: To conduct a preliminary examination to evaluate the feasibility of the use of an artificial pancreas for glucose control as well as the accuracy of assessment by the artificial pancreas of the insulin dose required. SUBJECTS AND METHODS: Glucose control using an artificial pancreas was undertaken in 8 postoperative sepsis patients. The blood glucose level was set at 80-150 mg/dl. Blood glucose levels over time, insulin dose requirements, and occurrence of hypoglycemia (≤40 mg/dl) were recorded for each patient. The patients were divided into 2 groups based on the total insulin dose they received over the 7 days (HG, n = 4: consisting of patients who required a higher insulin dose; LG, n = 4: patients who required a lower insulin dose). The data of the 2 groups were analyzed retrospectively. RESULTS: The blood glucose level before glucose control was 203.3 ± 9.9 mg/dl and could be controlled in all patients to within the target range. No hypoglycemia events were recorded for any of the patients. The insulin dose in the HG and LG groups was 21,824.8 ± 6,030.4 and 6,254.5 ± 3,402.3 mU/kg (p < 0.05). CONCLUSIONS: Accurate glucose control could be achieved with the artificial pancreas.


Asunto(s)
Glucemia/metabolismo , Hipoglucemia/prevención & control , Páncreas Artificial , Complicaciones Posoperatorias/prevención & control , Sepsis/sangre , Sepsis/cirugía , Anciano , Femenino , Glucosa/administración & dosificación , Humanos , Insulina/administración & dosificación , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Estudios Retrospectivos
6.
Eur Surg Res ; 47(3): 135-40, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21921634

RESUMEN

BACKGROUND: Endotoxin (Et) adsorption therapy with a column of polymyxin B-immobilized fibers (PMX) is effective in improving the partial pressure of arterial oxygen/fraction of inspired oxygen ratio (PaO(2)/FiO(2) ratio) and increasing mean arterial blood pressure (MAP) in sepsis. S100A12 and soluble receptor for advanced glycation end product (sRAGE) are useful as early markers of acute lung injury. PURPOSE: To investigate the effect of improving the PaO(2)/FiO(2) ratio by PMX-direct hemoperfusion (PMX-DHP) on production of S100A12 and sRAGE. SUBJECTS AND METHODS: Sepsis patients after surgery for perforation of the lower gastrointestinal tract were adopted as the subjects. We retrospectively reviewed the cases of 20 patients on mechanical ventilation and continuous administration of norepinephrine. We recorded PaO(2)/FiO(2) ratio, MAP, and norepinephrine doses. S100A12, sRAGE, and Et levels were measured before and after PMX-DHP. RESULTS: The PaO(2)/FiO(2) ratio and MAP improved significantly after PMX-DHP (p < 0.05). S100A12 and Et decreased significantly after PMX-DHP (p < 0.05). No differences were observed in sRAGE. CONCLUSION: S100A12 is useful as a marker that reflected improvement in the PaO(2)/FiO(2) ratio after PMX-DHP. We consider PMX-DHP to be useful as adjunctive therapy for sepsis that reduces the Et and corrects the pathology in the early stage.


Asunto(s)
Hemoperfusión/métodos , Complicaciones Posoperatorias/terapia , Receptores Inmunológicos/sangre , Proteínas S100/sangre , Choque Séptico/terapia , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Endotoxinas/sangre , Endotoxinas/aislamiento & purificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oxígeno/sangre , Polimixina B , Complicaciones Posoperatorias/sangre , Receptor para Productos Finales de Glicación Avanzada , Estudios Retrospectivos , Proteína S100A12 , Choque Séptico/sangre
7.
Kyobu Geka ; 64(4): 275-9, 2011 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-21491720

RESUMEN

BACKGROUND: Pneumothorax in middle-aged and elderly patients has various different features from young patients. We set out to investigate the outcome and usefulness of video-assisted thoracic surgery (VATS) in this group. PATIENTS AND METHODS: From January 1993 to August 2010, 168 patients underwent a total of 178 thoracoscopic surgeries. There were 160 men and 8 women with mean age of 67 (range, 50 to 85). The average duration of thoracic drainage before surgery was 7.4 days. We excised only responsible lesions as minimum degree of dissection as possible. When patients have intractable air leakage and chest computed tomography (CT) indicates severe pleural adhesions, pleurography should be performed to locate the site of air leakage and determine surgical approaches. One hundred and seventy patients were treated with the lateral approach, while 8 patients were successfully treated with the anterior approach. One hundred and fifty-one patients were treated with VATS alone, and 27 patients were treated with the combination of VATS and small thoracotomy. The duration of chest tube drainage, hospital stay, post-operative complication, outcome and recurrence were assessed. RESULTS: The air leakages stopped and all patients except for 2 patents were discharged without drainage tubes. Postoperative drainage time was 4.5 +/- 3.4 days. Postoperative hospital stay was 9.9 +/- 13.9 days. One patient died caused by perioperative myocardial infarction. Seventeen patients died of other diseases. Seven patients needed local hospital treatments and the recurrence rate was 3.9%. CONCLUSION: VATS for pneumothorax in patients over 50 years old is very useful by appropriate perioperative managements.


Asunto(s)
Neumotórax/cirugía , Cirugía Torácica Asistida por Video , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cirugía Torácica Asistida por Video/métodos , Toracotomía , Resultado del Tratamiento
8.
Nat Commun ; 12(1): 4356, 2021 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-34272371

RESUMEN

Thermoelectric effects have been applied to power generators and temperature sensors that convert waste heat into electricity. The effects, however, have been limited to electrons to occur, and inevitably disappear at low temperatures due to electronic entropy quenching. Here, we report thermoelectric generation caused by nuclear spins in a solid: nuclear-spin Seebeck effect. The sample is a magnetically ordered material MnCO3 having a large nuclear spin (I = 5/2) of 55Mn nuclei and strong hyperfine coupling, with a Pt contact. In the system, we observe low-temperature thermoelectric signals down to 100 mK due to nuclear-spin excitation. Our theoretical calculation in which interfacial Korringa process is taken into consideration quantitatively reproduces the results. The nuclear thermoelectric effect demonstrated here offers a way for exploring thermoelectric science and technologies at ultralow temperatures.

9.
Nat Commun ; 10(1): 5162, 2019 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-31727884

RESUMEN

Resonant enhancement of spin Seebeck effect (SSE) due to phonons was recently discovered in Y[Formula: see text]Fe[Formula: see text]O[Formula: see text] (YIG). This effect is explained by hybridization between the magnon and phonon dispersions. However, this effect was observed at low temperatures and high magnetic fields, limiting the scope for applications. Here we report observation of phonon-resonant enhancement of SSE at room temperature and low magnetic field. We observe in Lu[Formula: see text]BiFe[Formula: see text]GaO[Formula: see text] an enhancement 700% greater than that in a YIG film and at very low magnetic fields around 10[Formula: see text] T, almost one order of magnitude lower than that of YIG. The result can be explained by the change in the magnon dispersion induced by magnetic compensation due to the presence of non-magnetic ion substitutions. Our study provides a way to tune the magnon response in a crystal by chemical doping, with potential applications for spintronic devices.

10.
Kyobu Geka ; 61(10): 877-80, 2008 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-18788379

RESUMEN

We report a rare case of Bochdalek hernia, congenital posterolateral diaphragmatic hernia with volvulus of the stomach, in an adult A 74-year-old man was admitted to our hospital complaining of sudden abdominal pain and vomiting. Roentgenologic examination of the chest showed air above the left diaphragm, and the mediastinum was displaced to the right. Upper gastrointestinal series revealed volvulus of the stomach in which the pylorus was displaced to the left. The surgical repair was done through left thoracotomy with combining laparoscopy and thoracoscopy without surgical complications, 1 year later the patient is asymptomatic.


Asunto(s)
Hernia Diafragmática/complicaciones , Hernia Diafragmática/cirugía , Vólvulo Gástrico/complicaciones , Vólvulo Gástrico/cirugía , Anciano , Diafragma/cirugía , Hernia Diafragmática/diagnóstico , Humanos , Laparoscopía , Masculino , Estómago/cirugía , Vólvulo Gástrico/diagnóstico , Toracoscopía , Toracotomía , Resultado del Tratamiento
11.
J Int Med Res ; 34(4): 406-12, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16989497

RESUMEN

This study evaluated the efficacy and safety of barnidipine for the treatment of mild-to-moderate essential hypertension in Chinese patients. A total of 131 patients were randomized to receive either barnidipine (10 -15 mg) or felodipine (5 - 10 mg) once daily for 4 weeks. Both drugs reduced blood pressure significantly, with > or = 87% of patients obtaining a marked or moderate effect. The mean +/- SD reductions in systolic and diastolic blood pressure were 19.2 +/- 13.6 and 14.4 +/- 7.0 mmHg, respectively, for barnidipine treatment, and 20.3 +/- 11.3 and 14.7 +/- 7.7 mmHg, respectively, for felodipine treatment. There were no significant differences between the two drugs in terms of anti-hypertensive effect, heart rate, laboratory test results or incidence of adverse events. More patients taking felodipine experienced palpitations, but this difference was not statistically significant. Barnidipine is as efficacious and safe as felodipine in the treatment of essential hypertension in Chinese patients.


Asunto(s)
Antihipertensivos/uso terapéutico , Bloqueadores de los Canales de Calcio/uso terapéutico , Felodipino/uso terapéutico , Hipertensión/tratamiento farmacológico , Nifedipino/análogos & derivados , Adulto , Anciano , Pueblo Asiatico , Presión Sanguínea/efectos de los fármacos , China/etnología , Femenino , Humanos , Hipertensión/etnología , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Nifedipino/uso terapéutico
12.
J Int Med Res ; 34(2): 121-8, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16749407

RESUMEN

This study compared barnidipine, a calcium-channel blocker, and benazepril, an angiotensin-converting enzyme inhibitor, in 85 Chinese patients with renal parenchymal hypertension (diastolic blood pressure range 95 - 110 mmHg). Patients were randomly assigned to receive either 10 mg barnidipine or 10 mg benazepril orally daily for 4 weeks. In patients with diastolic blood pressure > 90 mmHg after 2 weeks of treatment, the dose of barnidipine or benazepril was increased by 5 or 10 mg, respectively. Both the barnidipine-treated group (n = 43) and the benazepril-treated group (n = 42) showed significant mean reductions from baseline in sitting systolic and diastolic blood pressures. The decrease in diastolic blood pressure with benazepril was significantly greater than with barnidipine treatment. Sitting heart rate was not changed by either drug. There was no significant difference in adverse events between the two groups. Barnidipine is similar to benazepril for the treatment of renal parenchymal hypertension.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Benzazepinas/uso terapéutico , Bloqueadores de los Canales de Calcio/uso terapéutico , Hipertensión Renal/tratamiento farmacológico , Nifedipino/análogos & derivados , Adolescente , Adulto , Anciano , Inhibidores de la Enzima Convertidora de Angiotensina/efectos adversos , Benzazepinas/efectos adversos , Presión Sanguínea/efectos de los fármacos , Bloqueadores de los Canales de Calcio/efectos adversos , China , Femenino , Humanos , Hipertensión Renal/fisiopatología , Masculino , Persona de Mediana Edad , Nifedipino/efectos adversos , Nifedipino/uso terapéutico
13.
Annu Int Conf IEEE Eng Med Biol Soc ; 2015: 4387-90, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26737267

RESUMEN

Measurements of dielectric constants and conductivities of invasive ductal carcinoma (IDC) tissues such as scirrhous carcinoma, solidtubular carcinoma and papillotubular carcinoma were made by use of microwave dielectric spectroscopy. Dielectric constants of inhomogeneous breast tumor tissues were analyzed by use of Bruggeman's effective medium approximation theory. It is found that the dielectric constants of scirrhous carcinoma, solidtubular carcinoma and papillotubular carcinoma of IDC tissues have correlation to the volume fractions of the cancer cells in the stroma tissues.


Asunto(s)
Neoplasias de la Mama , Humanos
14.
Atherosclerosis ; 48(2): 157-66, 1983 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6615580

RESUMEN

A marked reduction of serum cholesterol was obtained by treatment with probucol in heterozygous as well as in homozygous cases of familial hypercholesterolemia. A strict dietary regimen (low-fat, low-calories) intensified the hypocholesterolemic effect of the drug. The drug was also useful in diminishing the rebound of serum cholesterol after plasma exchange. Probucol reduced serum triglycerides in heterozygous cases of familial hypercholesterolemia, but there was a slight increase in triglycerides in homozygous cases. Treatment with probucol resulted in the regression of cutaneous and tendon xanthomas. Although it caused a decrease in HDL, it seems to be very effective in the treatment of familial hypercholesterolemia.


Asunto(s)
Hiperlipoproteinemia Tipo II/tratamiento farmacológico , Lovastatina/análogos & derivados , Fenoles/uso terapéutico , Probucol/uso terapéutico , Adolescente , Adulto , Anticolesterolemiantes/uso terapéutico , Colesterol/sangre , Ingestión de Energía , Femenino , Homocigoto , Humanos , Hiperlipoproteinemia Tipo II/terapia , Masculino , Persona de Mediana Edad , Naftalenos/uso terapéutico , Intercambio Plasmático , Enfermedades de la Piel/tratamiento farmacológico , Tendones , Triglicéridos/sangre , Xantomatosis/tratamiento farmacológico
15.
Kyobu Geka ; 57(9): 867-70, 2004 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-15366572

RESUMEN

A 70-year-old woman was referred to our department because of a solitary nodular shadow, 2 cm in diameter, in the right mid zone on a chest X-ray. Chest computed tomography revealed a pulmonary arteriovenous fistula (PAVF) in S4 of the right lung. Although the patient did not present with PAVF-related symptoms or hypoxemia, in view of the threat of serious complications, a therapeutic decision was made for coil embolization of the pulmonary artery feeding the PAVF. During the endovascular embolization procedure, the coil migrated into the mitral valve chordae tendinae. Urgent thoracotomy was therefore performed and the coil was safely retrieved from the site. Via the same thoracotomy incision, the PAVF with its surrounding tissue was also resected from the right lobe of the lung. The inadvertent coil migration in this patient may be explained by the fact that the fistula was not large enough to allow the coil to stay in place for the prevention of blood flow from the feeding vessel. These findings indicate that surgical resection of PAVF should be selected when the size of the fistula is too small for coil embolization. Otherwise, if transcatheter embolization is preferred, the detachable balloon approach may be appropriate.


Asunto(s)
Fístula Arteriovenosa/cirugía , Embolización Terapéutica/instrumentación , Migración de Cuerpo Extraño/cirugía , Arteria Pulmonar , Venas Pulmonares , Toracotomía , Anciano , Remoción de Dispositivos , Falla de Equipo , Femenino , Humanos
16.
Kyobu Geka ; 57(5): 347-50; discussion 350-2, 2004 May.
Artículo en Japonés | MEDLINE | ID: mdl-15151030

RESUMEN

From August 1997 to December 2002, 14 consecutive patients with superior vena cava syndrome with the self-expanding endovascular prosthesis. Diagnoses were adenocarcinoma in 6, small cell carcinoma in 4, squamous cell carcinoma in 1, metastatic lung cancer in 2, and invasive thymoma in 1. Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) were measured on their admission and perioperative period. Expecting only 1 patient complete symptomatically relieved within 3 days of stent implantation. Superior vena cava pressure or radial pressure of the stent was sufficient to relieve obstruction. Preoperative ANP level were normal, BNP level were increased. Postoperatively both ANP level and BNP level were slightly increased under intravenous dopamine hydrochloride. Implantation of the self-expanding stent endovascular prosthesis for superior vena cava syndrome provides rapid symptomatic relief and improves the patient's quality of life.


Asunto(s)
Factor Natriurético Atrial/sangre , Péptido Natriurético Encefálico/sangre , Stents , Síndrome de la Vena Cava Superior/fisiopatología , Síndrome de la Vena Cava Superior/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Neoplasias Pulmonares/complicaciones , Masculino , Persona de Mediana Edad , Pronóstico , Prótesis e Implantes , Calidad de Vida
17.
J Phys Condens Matter ; 26(34): 343202, 2014 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-25105889

RESUMEN

The spin Seebeck effect refers to the generation of spin voltage as a result of a temperature gradient in ferromagnetic or ferrimagnetic materials. When a conductor is attached to a magnet under a temperature gradient, the thermally generated spin voltage in the magnet injects a spin current into the conductor, which in turn produces electric voltage owing to the spin-orbit interaction. The spin Seebeck effect is of increasing importance in spintronics, since it enables direct generation of a spin current from heat and appears in a variety of magnets ranging from metals and semiconductors to insulators. Recent studies on the spin Seebeck effect have been conducted mainly in paramagnetic metal/ferrimagnetic insulator junction systems in the longitudinal configuration in which a spin current flowing parallel to the temperature gradient is measured. This 'longitudinal spin Seebeck effect' (LSSE) has been observed in various sample systems and exclusively established by separating the spin-current contribution from extrinsic artefacts, such as conventional thermoelectric and magnetic proximity effects. The LSSE in insulators also provides a novel and versatile pathway to thermoelectric generation in combination of the inverse spin-Hall effects. In this paper, we review basic experiments on the LSSE and discuss its potential thermoelectric applications with several demonstrations.

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