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1.
Nature ; 558(7708): 95-99, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29785052

RESUMEN

The Peltier effect, discovered in 1834, converts a charge current into a heat current in a conductor, and its performance is described by the Peltier coefficient, which is defined as the ratio of the generated heat current to the applied charge current1,2. To exploit the Peltier effect for thermoelectric cooling or heating, junctions of two conductors with different Peltier coefficients have been believed to be indispensable. Here we challenge this conventional wisdom by demonstrating Peltier cooling and heating in a single material without junctions. This is realized through an anisotropic magneto-Peltier effect in which the Peltier coefficient depends on the angle between the directions of a charge current and magnetization in a ferromagnet. By using active thermography techniques3-10, we observe the temperature change induced by this effect in a plain nickel slab. We find that the thermoelectric properties of the ferromagnet can be redesigned simply by changing the configurations of the charge current and magnetization, for instance, by shaping the ferromagnet so that the current must flow around a curve. Our experimental results demonstrate the suitability of nickel for the anisotropic magneto-Peltier effect and the importance of spin-orbit interaction in its mechanism. The anisotropic magneto-Peltier effect observed here is the missing thermoelectric phenomenon in ferromagnetic materials-the Onsager reciprocal of the anisotropic magneto-Seebeck effect previously observed in ferromagnets-and its simplicity might prove useful in developing thermal management technologies for electronic and spintronic devices.

2.
Nature ; 560(7720): E36, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29907793

RESUMEN

In this Letter, owing to an error during the production process, 'θH' was incorrectly written as 'θΗH' six times in the paragraph starting "Up to now,…". These errors have been corrected online.

3.
Nat Mater ; 20(4): 463-467, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33462463

RESUMEN

When a temperature gradient is applied to a closed circuit comprising two different conductors, a charge current is generated via the Seebeck effect1. Here, we utilize the Seebeck-effect-induced charge current to drive 'transverse' thermoelectric generation, which has great potential for energy harvesting and heat sensing applications owing to the orthogonal geometry of the heat-to-charge-current conversion2-9. We found that, in a closed circuit comprising thermoelectric and magnetic materials, artificial hybridization of the Seebeck effect into the anomalous Hall effect10 enables transverse thermoelectric generation with a similar symmetry to the anomalous Nernst effect11-27. Surprisingly, the Seebeck-effect-driven transverse thermopower can be several orders of magnitude larger than the anomalous-Nernst-effect-driven thermopower, which is clearly demonstrated by our experiments using Co2MnGa/Si hybrid materials. The unconventional approach could be a breakthrough in developing applications of transverse thermoelectric generation.

4.
Phys Rev Lett ; 128(4): 047601, 2022 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-35148138

RESUMEN

We formulate a scattering theory of polarization and heat transport through a ballistic ferroelectric point contact. We predict a polarization current under either an electric field or a temperature difference that depends strongly on the direction of the ferroelectric order and can be detected by its magnetic stray field and associated thermovoltage and Peltier effect.

5.
Hinyokika Kiyo ; 68(2): 67-70, 2022 Feb.
Artículo en Japonés | MEDLINE | ID: mdl-35259867

RESUMEN

Testicular epidermoid cysts are relatively rare, accounting for about 1% of all testicular tumors, and are often treated by high orchiectomy. We describe here the case of a testicular epidermoid cyst treated by testicle-sparing surgery due to a preoperative diagnosis. A 23-year-old man complained of a painless mass in the right scrotum. Physical examination revealed a firm little fingertip-sized smooth-surfaced mass in the right testis. Ultrasonography showed a hypoechoic lesion with an echogenic rim in the right testis. A T2-weighted magnetic resonance image showed a well-demarcated mass with a low signal outline. On the basis of a preoperative diagnosis of epidermoid cyst, intraoperative testicular frozen section was performed, and the mass was resected surgically while preserving the testis.


Asunto(s)
Quiste Epidérmico , Enfermedades Testiculares , Adulto , Quiste Epidérmico/diagnóstico por imagen , Quiste Epidérmico/cirugía , Humanos , Masculino , Orquiectomía , Enfermedades Testiculares/diagnóstico por imagen , Enfermedades Testiculares/cirugía , Ultrasonografía , Adulto Joven
6.
Phys Rev Lett ; 126(18): 187603, 2021 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-34018785

RESUMEN

The spontaneous order of electric and magnetic dipoles in ferroelectrics and ferromagnets even at high temperatures is both fascinating and useful. Transport of magnetism in the form of spin currents is vigorously studied in spintronics, but the polarization current of the ferroelectric order has escaped attention. We therefore present a time-dependent diffusion theory for heat and polarization transport in a planar ferroelectric capacitor with parameters derived from a one-dimensional phonon model. We predict steady-state Seebeck and transient Peltier effects that await experimental discovery.

7.
Phys Rev Lett ; 125(10): 106601, 2020 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-32955334

RESUMEN

We report the observation of the higher-order thermoelectric conversion based on a magneto-Thomson effect. By means of thermoelectric imaging techniques, we directly observed the temperature change induced by the Thomson effect in a polycrystalline Bi_{88}Sb_{12} alloy under a magnetic field and found that the magnetically enhanced Thomson coefficient can be comparable to or even larger than the Seebeck coefficient. Our experiments reveal the significant contribution of the higher-order magnetothermoelectric conversion, opening the door to "nonlinear spin caloritronics."

8.
Hinyokika Kiyo ; 66(9): 313-317, 2020 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-32988169

RESUMEN

A 74-year-old man presented with further treatment for muscle invasive small cell carcinoma of the bladder. After three courses of neoadjuvant chemotherapy with cisplatine + etoposide (EP), total cystectomy was performed. The pathological findings revealed small cell carcinoma of the bladder (ypT2N0M0). Eleven months after the operation, thoracoabdominal computed tomography (CT) showed right pelvic lymph node metastasis. He underwent 9 courses of EP chemotherapy, and everolimus, finally, Amrubicin was administered. Amrubicin might be useful for small cell carcinoma of the bladder.


Asunto(s)
Carcinoma de Células Pequeñas/diagnóstico por imagen , Carcinoma de Células Pequeñas/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/cirugía , Anciano , Cistectomía , Etopósido , Humanos , Masculino
9.
Hinyokika Kiyo ; 63(9): 363-369, 2017 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-28992666

RESUMEN

Bladder tamponade is thought to be caused mainly by bladder cancer or radiation cystitis. However, in women, it may often be caused by cystitis in clinical settings. This has not been noted in previous reports of bladder tamponade in Japan. Thus, we retrospectively analyzed the clinical features of 83 male and 41 female patients with bladder tamponade. Seventy-four patients were treated at Nishi-Kobe Medical Center between April 2005 and March 2015, and 50 were treated at Shizuoka City Shizuoka Hospital between November 2008 and March 2015. The patients'median age was 80 years. The cause of bladder tamponade was urological malignancies in 33 of the 83 male patients (40%), benign prostatic hyperplasia in 20 of the 83 male patients (24%), and cystitis in 33 of the 41 female patients (80%). Compared with the men, the women with bladder tamponade were significantly older and the proportion of patients with cerebrovascular disease, diabetes, and dementia was higher. In addition, more women were nursing home residents, with a higher rate of voiding with diapers and antithrombotic use than men. Causative strains of cystitis were diverse, and some were antibiotic resistant. Most of the cases of bladder tamponade in the women occurred in the elderly and were caused by cystitis. In an aging society, increases in the incidences of chronic, complicated cystitis due to impaired independent micturition, dysuria, and systemic diseases such as diabetes, and increased use of antithrombotic drugs may contribute to bladder tamponade in women.


Asunto(s)
Cistitis/complicaciones , Obstrucción Ureteral/etiología , Enfermedades de la Vejiga Urinaria/etiología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estaciones del Año
10.
Hinyokika Kiyo ; 61(3): 99-102, 2015 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-25918267

RESUMEN

Cholesterol crystal embolization (CCE) is a cardiovascular disorder with poor prognosis, causing multiple organ failure. The primary pathological condition of the disease is embolization of cholesterol crystals in peripheral vessels. We report a case of CCE following urinary diversion. The patient is a 82-year-old male with history of hypertention, pneumonectasia, interstitial pneumonia, and heavy smoking. He was afflicted with advanced bladder cancer. He underwent urinary diversion, and had been scheduled for palliative radiotherapy. The next day, he developed thromboembolism of the left lower leg as acomplication of urinary diversion. Thrombectomy by endovascular catheter procedure was performed immediately, and anticoagulant therapy was started. The day after the thrombectomy, his lower legs showed livedo reticularis and toes showed cyanosis (blue toe). Since the laboratory data showed acute deterioration in renal function, hemodialysis was initiated. Three days after the thrombectomy he died of multiple organ failure. At autopsy, diffuse atherosclerosis of the aorta was observed, and cholesterol crystalemboli were found in the skin of the left foot ; and, the diagnosis of CCE was confirmed. This case suggests that tissue examinations for early diagnosis and stopping anticoagulant therapy are preferred when CCE is suspected.


Asunto(s)
Embolia por Colesterol/etiología , Complicaciones Posoperatorias , Neoplasias de la Vejiga Urinaria/cirugía , Derivación Urinaria/efectos adversos , Anciano de 80 o más Años , Embolia por Colesterol/diagnóstico , Resultado Fatal , Humanos , Masculino , Invasividad Neoplásica , Tomografía Computarizada por Rayos X , Neoplasias de la Vejiga Urinaria/patología
11.
Sci Adv ; 9(5): eadd7194, 2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36724270

RESUMEN

This article shows experimentally that an external electric field affects the velocity of the longitudinal acoustic phonons (vLA), thermal conductivity (κ), and diffusivity (D) in a bulk lead zirconium titanate-based ferroelectric. Phonon conduction dominates κ, and the observations are due to changes in the phonon dispersion, not in the phonon scattering. This gives insight into the nature of the thermal fluctuations in ferroelectrics, namely, phonons labeled ferrons that carry heat and polarization. It also opens the way for phonon-based electrically driven all-solid-state heat switches, an enabling technology for solid-state heat engines. A quantitative theoretical model combining piezoelectric strain and phonon anharmonicity explains the field dependence of vLA, κ, and D without any adjustable parameters, thus connecting thermodynamic equilibrium properties with transport properties. The effect is four times larger than previously reported effects, which were ascribed to field-dependent scattering of phonons.

12.
Hinyokika Kiyo ; 58(11): 617-9, 2012 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-23254787

RESUMEN

A 67-year-old man was referred to our hospital for evaluation of large urinary-diversion calculus. He had undergone urinary diversion for invasive bladder cancer with an Indiana pouch, when he was 52 years old. We performed the surgery using a laparoscopic trocar and an entrapment bag, for reducing the risk of bladder damage by the lithoclast and small residual fragments of the calculus. There has been no recurrence of stone formation 18 months after the surgery. This technique of percutaneous cystolithotomy of a large urinary calculus utilizing laparoscopic and endourologic instrumentation, is quick and safe, and can be used for complete stone removal, thereby decreasing the risk of recurrent stone formation.


Asunto(s)
Laparoscopía/instrumentación , Cálculos Urinarios/terapia , Anciano , Humanos , Masculino , Neoplasias de la Vejiga Urinaria/cirugía , Cálculos Urinarios/etiología , Derivación Urinaria/efectos adversos
13.
Hinyokika Kiyo ; 58(9): 515-8, 2012 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-23070394

RESUMEN

A 67-year old man was diagnosed with advanced prostate cancer with multiple pelvic lymph nodes and multiple bone metastases (cT2N1M1b), with an initial prostate specific antigen of 1,300 ng/ml. Prostate biopsy specimens revealed poorly differentiated adenocarcinoma, Gleason's score 5+3. He was treated with maximal androgen blockade (MAB) from 2001, but showed resistance to hormone therapy and docetaxel in 2007. External radiation therapy for bone pain was difficult due to multiple lesions. 89Sr therapy was started in 2009. The therapy could be performed 5 times without any side effects. Good pain control and decreasing PSA was obtained at each dose.


Asunto(s)
Adenocarcinoma/radioterapia , Resistencia a Antineoplásicos , Orquiectomía , Neoplasias de la Próstata/radioterapia , Radioisótopos de Estroncio/uso terapéutico , Adenocarcinoma/terapia , Anciano , Docetaxel , Humanos , Masculino , Neoplasias de la Próstata/terapia , Taxoides/uso terapéutico
14.
Hinyokika Kiyo ; 57(5): 237-41, 2011 May.
Artículo en Japonés | MEDLINE | ID: mdl-21743280

RESUMEN

A 75-year-old man was admitted to our hospital with liver dysfunction and elevated C-reactive protein level. He was diagnosed with renal tumor by ultrasonography. Computed tomography revealed a renal cell carcinoma (cT3aN0M0) with Stauffer syndrome. Laparoscopic radical nephrectomy was performed. Histological findings indicated clear cell carcinoma with a sarcomatoid component. After 1 month, lung metastasis was detected on an X-ray film. Interferon-α was administered, and complete response was achieved 2 months later. He has shown no evidence of recurrence in 27 months.


Asunto(s)
Carcinoma de Células Renales/patología , Carcinoma de Células Renales/cirugía , Interferón-alfa/uso terapéutico , Neoplasias Renales/patología , Neoplasias Renales/cirugía , Hepatopatías/etiología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/secundario , Nefrectomía , Anciano , Carcinoma de Células Renales/complicaciones , Humanos , Neoplasias Renales/complicaciones , Laparoscopía , Masculino , Síndrome
15.
Intern Med ; 60(11): 1717-1722, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33431734

RESUMEN

A 47-year-old Japanese man was referred to our hospital because of a sustained high fever with diarrhea 12 days after a flight from India. Liver enzymes were elevated with rose spots, hepatosplenomegaly, relative bradycardia, and acute cholecystitis. A liver biopsy depicted the dense infiltration of lymphocytes and Kupffer cells in sinusoids and the granulomatous formation in the parenchyma. The liver damage was initially resolved with the administration of ceftriaxone for 16 days but flared up 1 week later. Laboratory tests yielded positive reactions for Salmonella typhi and hepatitis E virus RNA. The pathophysiological presentations of concurrent typhoid and type E hepatitis are discussed.


Asunto(s)
Virus de la Hepatitis E , Hepatitis , Sobreinfección , Antibacterianos/uso terapéutico , Hepatitis/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Salmonella typhi , Sobreinfección/tratamiento farmacológico
16.
Hinyokika Kiyo ; 56(2): 95-8, 2010 Feb.
Artículo en Japonés | MEDLINE | ID: mdl-20185994

RESUMEN

We evaluated the relationship between the type of suture and occurrence of anastomotic stricture after radical retropubic prostatectomy (RRP). From April 2005 to February 2008, 48 RRP were performed. In the former 24 cases, 2-0 absorbable braided sutures were used (group A), and in the latter 24 cases, 3-0 absorbable monofilament sutures were used (group B) in the vesicourethral anastomosis. In group B, operation time was longer, blood loss was less and tumor stage was lower. While five patients in group A developed an anastomotic stricture, but no one in group B developed a stricture. Univariate analysis of the two groups revealed that only the type of suture and age were significant parameters for the anastomotic stricture.


Asunto(s)
Anastomosis Quirúrgica/efectos adversos , Prostatectomía/métodos , Suturas , Factores de Edad , Anciano , Constricción Patológica , Humanos , Masculino , Complicaciones Posoperatorias , Prostatectomía/efectos adversos
17.
Hinyokika Kiyo ; 55(12): 777-81, 2009 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-20048565

RESUMEN

A Leydig cell tumor is a rare disease entity occurring in the testis. Occasionally it is considered to be related to male infertility. We report a case study of a Leydig cell tumor in a single testis presenting as male infertility. A 38-year-old male was referred to our hospital because of a tumor in his right testis. He had undergone left orchiectomy at one year old because of a testicular tumor. During an examination related to the infertility, ultrasound revealed a 1 cm tumor. Tumor markers were all within normal ranges.Hormonal examination showed that luteinizing hormone (LH) 30.3 mIU/ml (1.5-12.4) and follicle stimulating hormone (FSH) 11.9 mIU/ml (1.7-8.6) were higher than normal limits, but total testosterone(total T) and estradiol (E2) were within normal ranges. Tumor enucleation was first performed, and then testicular sperm extraction (TESE) was carried out from a macroscopically normal site of the testis.Histopathological diagnosis was a benign Leydig cell tumor surrounded by Leydig cell hyperplasia. For 12 months after the operation there has been no recurrence. Although high LH and FSH persisted, total T and E2 were within normal ranges.


Asunto(s)
Infertilidad Masculina/etiología , Tumor de Células de Leydig/complicaciones , Neoplasias Testiculares/complicaciones , Adulto , Humanos , Tumor de Células de Leydig/cirugía , Masculino , Neoplasias Testiculares/cirugía
18.
Hinyokika Kiyo ; 55(8): 483-5, 2009 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-19764533

RESUMEN

A 32-year-old man was referred to our hospital for evaluation of bilateral renal tumors 8 cm each in diameter. His cousin also had a renal tumor, and she had been genetically diagnosed as von Hippel-Lindau (VHL) disease. Bilateral nephron-sparing surgery was performed in separate stages under clinical diagnosis of renal cell carcinoma and VHL disease. Histological examination revealed clear cell renal cell carcinoma (pT2). There was no evidence of local recurrence or metastasis 6 months after the second operation. In the treatment of renal cell carcinoma and VHL disease, nephron-sparing surgery is recommended to achieve a disease-free status without renal replacement therapy.


Asunto(s)
Carcinoma de Células Renales/cirugía , Neoplasias Renales/cirugía , Enfermedad de von Hippel-Lindau/complicaciones , Adulto , Carcinoma de Células Renales/etiología , Humanos , Neoplasias Renales/etiología , Masculino , Procedimientos Quirúrgicos Urológicos/métodos
19.
Sci Rep ; 9(1): 18443, 2019 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-31804550

RESUMEN

The magnetic skyrmion is a nanoscale topological object characterized by the winding of magnetic moments, appearing in magnetic materials with broken inversion symmetry. Because of its low current threshold for driving the skyrmion motion, they have been intensely studied toward novel storage applications by using electron-beam, X-ray, and visible light microscopies. Here, we demonstrate another imaging method for skyrmions by using spin-caloritronic phenomena, that is, the spin Seebeck and anomalous Nernst effects, as a probe of magnetic texture. We scanned a focused heating spot on a Hall-cross shaped MgO/CoFeB/Ta/W multilayer film and mapped the magnitude as well as the direction of the resultant thermoelectric current due to the spin-caloritronic phenomena. Our experimental and calculation reveal that the characteristic patterns in the thermoelectric signal distribution reflect the skyrmions' magnetic texture. The thermoelectric microscopy will be a complementary and useful imaging technique for the development of skyrmion devices owing to the unique symmetry of the spin-caloritronic phenomena.

20.
Sci Rep ; 9(1): 13197, 2019 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-31519954

RESUMEN

Since the charge current plays a major role in information processing and Joule heating is inevitable in electronic devices, thermal management, i.e., designing heat flows, is required. Here, we report that strain application can change a direction of a heat current generated by magneto-thermoelectric effects. For demonstration, we used metallic magnets in a thin-film form, wherein the anomalous Ettingshausen effect mainly determines the direction of the heat flow. Strain application can alter the magnetization direction owing to the magnetoelastic effect. As a result, the heat current, which is in the direction of the cross product of the charge current and the magnetization vector, can be switched or rotated simply by applying a tensile strain to the metallic magnets. We demonstrate 180° switching and 90° rotation of the heat currents in an in-plane magnetized Ni sample on a rigid sapphire substrate and a perpendicularly magnetized TbFeCo film on a flexible substrate, respectively. An active thermography technique was used to capture the strain-induced change in the heat current direction. The method presented here provides a novel method for controlling thermal energy in electronic devices.

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