The generation of electric voltage by placing a conductor in a temperature gradient is called the Seebeck effect. Its efficiency is represented by the Seebeck coefficient, S, which is defined as the ratio of the generated electric voltage to the temperature difference, and is determined by the scattering rate and the density of the conduction electrons. The effect can be exploited, for example, in thermal electric-power generators and for temperature sensing, by connecting two conductors with different Seebeck coefficients, a device called a thermocouple. Here we report the observation of the thermal generation of driving power, or voltage, for electron spin: the spin Seebeck effect. Using a recently developed spin-detection technique that involves the spin Hall effect, we measure the spin voltage generated from a temperature gradient in a metallic magnet. This thermally induced spin voltage persists even at distances far from the sample ends, and spins can be extracted from every position on the magnet simply by attaching a metal. The spin Seebeck effect observed here is directly applicable to the production of spin-voltage generators, which are crucial for driving spintronic devices. The spin Seebeck effect allows us to pass a pure spin current, a flow of electron spins without electric currents, over a long distance. These innovative capabilities will invigorate spintronics research.

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Using the spin Hall effect, magnetization relaxation in a Ni_{81}Fe_{19}/Pt film is manipulated electrically. An electric current applied to the Pt layer exerts spin torque on the entire magnetization of the Ni81Fe19 layer via the macroscopic spin transfer induced by the spin Hall effect and modulates the magnetization relaxation in the Ni81Fe19 layer. This method allows us to tune the magnetization dynamics regardless of the film size without applying electric currents directly to the magnetic layer.

Background Lipoinjection is a promising treatment but has some problems, such as unpredictability and a low rate of graft survival due to partial necrosis. Methods To overcome the problems with lipoinjection, the authors developed a novel strategy known as cellassisted lipotransfer (CAL). In CAL, autologous adiposederived stem (stromal) cells (ASCs) are used in combination with lipoinjection. A stromal vascular fraction (SVF) containing ASCs is freshly isolated from half of the aspirated fat and recombined with the other half. This process converts relatively ASC-poor aspirated fat to ASC-rich fat. This report presents the findings for 40 patients who underwent CAL for cosmetic breast augmentation.Results Final breast volume showed augmentation by 100 to 200 ml after a mean fat amount of 270 ml was injected. Postoperative atrophy of injected fat was minimal and did not change substantially after 2 months. Cyst formation or microcalcification was detected in four patients. Almost all the patients were satisfied with the soft and naturalappearing augmentation. Conclusions The preliminary results suggest that CAL is effective and safe for soft tissue augmentation and superior to conventional lipoinjection. Additional study is necessary to evaluate the efficacy of this technique further.

The inverse spin-Hall effect (ISHE) induced by the spin pumping has been investigated systematically in simple ferromagnetic/paramagnetic bilayer systems. The spin pumping driven by ferromagnetic resonance injects a spin current into the paramagnetic layer, which gives rise to an electromotive force transverse to the spin current using the ISHE in the paramagnetic layer. In a Ni81Fe19/Pt film, we found an electromotive force perpendicular to the applied magnetic field at the ferromagnetic resonance condition. The spectral shape of the electromotive force is well reproduced using a simple Lorentz function, indicating that the electromotive force is due to the ISHE induced by the spin pumping; extrinsic magnetogalvanic effects are eliminated in this measurement. The electromotive force varies systematically by changing the microwave power, magnetic-field angle, and film size, being consistent with the prediction based on the Landau–Lifshitz–Gilbert equation combined with the models of the ISHE and spin pumping. The electromotive force was observed also in a Pt/Y3Fe4GaO12 film, in which the metallic Ni81Fe19 layer is replaced by an insulating Y3Fe4GaO12 layer, supporting that the spin-pumping-induced ISHE is responsible for the observed electromotive force.

Our results suggest that CAL is both effective and safe and potentially superior to conventional lipoinjection for facial recontouring. The authors have indicated no significant interest with commercial supporters.

We have transferred 74 free or pedicled anterolateral thigh flaps, including those combined with other flaps, for reconstruction of various types of defects. We report several anatomic variations of the lateral circumflex arterial system and discuss some technical problems with this flap. Septocutaneous perforators were found in 28 of 74 cases (37.8 percent), and no perforators were found in 4 cases (5.4 percent). In the 70 cases with perforators, 171 tiny cutaneous perforators (an average of 2.31 per case) were found. Musculocutaneous perforators (81.9 percent) were much more common than septocutaneous perforators (18.1 percent). Perforators were concentrated near the midpoint of the lateral thigh, and the selection of perforators as nutrient vessels for the anterolateral thigh flap was related to the length of the pedicle and the thickness of the skin flap. Anatomic variations of the branching pattern of perforators were classified into eight types. Flaps with perforators that arise directly from the profunda femoris artery are difficult to combine with other free flaps. Because the perforators are extremely small and tend to thrombose soon after congestion develops, these flaps are difficult to salvage with recirculation surgery. Therefore, several perforators should be included with the flap, if possible. The descending artery of the lateral circumflex femoral artery was always accompanied by two veins with different back-flow strengths. Therefore, veins for microsurgical anastomosis must be chosen carefully. Because it is nourished by several perforators arising from the descending artery, the vastus lateralis muscle can be combined with the anterolateral thigh flap. However, splitting the muscle longitudinally without harvesting its blood supply is complicated because its fibers are oblique. The rectus femoris muscle can also be combined with the anterolateral thigh flap, but its pedicle is short and its origin is very near the site of anastomosis. When the anterolateral thigh flap is combined with the tensor fasciae latae musculocutaneous flap, the large skin area of the lateral part of thigh can be transferred to repair the massive defects. The anterolateral thigh flap has many advantages and can be used to reconstruct many types of defect. However, anatomic variations must be considered if the flap is to be used safely and reliably.

Microvascular free tissue transfer has gained world-wide acceptance as a means of reconstructing post-oncologic surgical defects in the head and neck region. Since 1977, the authors have introduced this reconstructive procedure to head and neck reconstruction after cancer ablation, and a total of 2372 free flaps were transferred in 2301 patients during a period of over 23 years. The most frequently used flap was the rectus abdominis flap (784 flaps: 33.1 percent), followed by the jejunum (644 flaps: 27.2 percent) and the forearm flap (384 flaps: 16.2 percent). In the reported series, total and partial flap necrosis accounted for 4.2 percent and 2.5 percent of cases, respectively. There was a significant statistical difference ( p < 0.05) in complete flap survival rate between immediate and secondary reconstruction cases. The authors believe that the above-mentioned three flaps have been a major part of the armamentarium for head and neck reconstruction because of a lower rate of flap necrosis, compared to other flaps.