Electric field-dependent phonon spectrum and heat conduction in ferroelectrics.

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.

[Testicular Preservation in a Patient with a Testicular Epidermoid Cyst Achieved by Preoperative Diagnosis : A Case Report].

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.

Thermoelectric Polarization Transport in Ferroelectric Ballistic Point Contacts.

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.

Theory of Transport in Ferroelectric Capacitors.

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.

Seebeck-driven transverse thermoelectric generation.

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.

A Superinfection of Salmonella typhi and Hepatitis E Virus Causes Biphasic Acute Hepatitis.

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.

[A Case of Small Cell Carcinoma of the Bladder].

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.

Observation of the Magneto-Thomson Effect.

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."

Thermoelectric microscopy of magnetic skyrmions.

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.

Strain-induced switching of heat current direction generated by magneto-thermoelectric effects.

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.

Combinatorial investigation of spin-orbit materials using spin Peltier effect.

Conversion between spin and charge currents is essential in spintronics, since it enables spin-orbit-torque magnetization switching, spin-current-driven thermoelectric generation, and nano-scale thermal energy control. To realize efficient spin-charge conversion, a variety of mechanisms, including spin Hall effects, Rashba-Edelstein effects, and spin-momentum locking in topological insulators, have been investigated and more comprehensive material exploration is necessary. Here we demonstrate high-throughput screening of spin-charge conversion materials by means of the spin Peltier effect (SPE). This is enabled by combining recently-developed SPE-imaging techniques with combinatorial materials science; using a composition-spread alloy film formed on a magnetic insulator, we observe the SPE-induced temperature change due to the spin Hall effect and obtain a continuous mapping of its composition dependence from the single sample. The distribution of the SPE signals reflects local spin-charge conversion capability in the alloy owing to unique heat-generation nature of the SPE. This combinatorial approach will accelerate materials research towards high-performance spintronic devices.

Publisher Correction: Observation of anisotropic magneto-Peltier effect in nickel.

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.

Observation of anisotropic magneto-Peltier effect in nickel.

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.

[An Increase in Cases of Bladder Tamponade Due to Cystitis Among Elderly Women and Clinical Background Factors].

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.

Generation of megahertz-band spin currents using nonlinear spin pumping.

Spin pumping enables the generation of d.c. and gigahertz-band (GHz-band) voltages from an applied microwave via magnetization dynamics when combined with inverse spin Hall effects. However, generating such voltages in the in-between frequency region, or the megahertz (MHz) band, has been difficult since ferromagnetic resonance usually occurs in the GHz band. Here we show that in spite of GHz-band microwaves applied, MHz-band voltages can be generated by spin pumping with use of nonlinear magnetization dynamics in Y3Fe5O12. The mechanism is ascribed to the MHz-band oscillation of the amplitude of the magnetization precession, which is projected onto a rectified voltage component via spin pumping. The present finding could be useful for frequency down-conversion thanks to the simple and durable structure, continuous-wave operation, and the tunability of an output frequency with low magnetic fields.

All-optical observation and reconstruction of spin wave dispersion.

To know the properties of a particle or a wave, one should measure how its energy changes with its momentum. The relation between them is called the dispersion relation, which encodes essential information of the kinetics. In a magnet, the wave motion of atomic spins serves as an elementary excitation, called a spin wave, and behaves like a fictitious particle. Although the dispersion relation of spin waves governs many of the magnetic properties, observation of their entire dispersion is one of the challenges today. Spin waves whose dispersion is dominated by magnetostatic interaction are called pure-magnetostatic waves, which are still missing despite of their practical importance. Here, we report observation of the band dispersion relation of pure-magnetostatic waves by developing a table-top all-optical spectroscopy named spin-wave tomography. The result unmasks characteristics of pure-magnetostatic waves. We also demonstrate time-resolved measurements, which reveal coherent energy transfer between spin waves and lattice vibrations.

Thermal imaging of spin Peltier effect.

The Peltier effect modulates the temperature of a junction comprising two different conductors in response to charge currents across the junction, which is used in solid-state heat pumps and temperature controllers in electronics. Recently, in spintronics, a spin counterpart of the Peltier effect was observed. The 'spin Peltier effect' modulates the temperature of a magnetic junction in response to spin currents. Here we report thermal imaging of the spin Peltier effect; using active thermography technique, we visualize the temperature modulation induced by spin currents injected into a magnetic insulator from an adjacent metal. The thermal images reveal characteristic distribution of spin-current-induced heat sources, resulting in the temperature change confined only in the vicinity of the metal/insulator interface. This finding allows us to estimate the actual magnitude of the temperature modulation induced by the spin Peltier effect, which is more than one order of magnitude greater than previously believed.

A Prospective Randomized Trial Comparing a Combined Regimen of Amikacin and Levofloxacin to Levofloxacin Alone as Prophylaxis in Transrectal Prostate Needle Biopsy.

PURPOSE: We investigated whether addition of amikacin to levofloxacin-based antimicrobial prophylaxis reduces febrile urinary tract infections after transrectal ultrasound-guided prostate needle biopsy (TRUSB). MATERIALS AND METHODS: A total of 447 patients undergoing TRUSB were prospectively randomized into two groups. The 230 patients in Group A were given one oral dose of levofloxacin 400 mg prior to TRUSB; the 217 patients in Group B each received the same dose of levofloxacin and one 200 mg intravenous dose of amikacin. Patients' characteristics were assessed prior to TRUSB and their symptoms were checked after the TRUSB. RESULTS: Both regimens were well tolerated with no side effects. No statistically significant difference in patients' characteristics, or in incidence of inflammation- or infection-related symptoms was seen between the two groups; nor any significant difference among those who developed fever and those who did not. Two Group A patients and one Group B patient developed febrile urinary tract infections. Accountable pathogens determined by urine and blood cultures were fluoroquinolone-resistant E.coli and extended-spectrum ß-lactamase-producing E.coli. All pathogens isolated were levofloxacin-resistant, amikacin-susceptible species. CONCLUSION: Although the present study was under-powered by unexpectedly low overall incidence of febrile urinary tract infections, addition of one intravenous administration of amikacin to one oral administration of levofloxacin showed no advantage compared with levofloxacin alone as antimicrobial prophylaxis in TRUSB. Strikingly, all pathogens isolated from febrile patients were sensitive to amikacin in vitro. Therefore, further understanding of amikacin's drug kinetics in the prostate is necessary to develop a more efficient drug delivery system for amikacin.

[Cholesterol crystal embolization following urinary diversion: a case report].

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.