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Since data transfer between memories and CPUs or MPUs becomes a bottle-neck for AI applications, in-memory computing becomes one of the hot topics. While, SOT-MRAM and VoCSM were reported to have both low energy consumption and nonvolatility [1] . VoCSM was also reported to work as logic-gates as well as nonvolatile working memories [2] . In this paper, SOT-MRAM and VoCSM and their application to Binary Neural Networks (B.N.N) are reviewed.

We report the existence of a spin-orbit torque generated from charge to spin conversion in perpendicularly magnetized ferromagnetic material through spin-torque ferromagnetic resonance (ST-FMR) measurement. We fabricated a trilayer structure consisting of a Cu spacer layer sandwiched between an in-plane magnetized FeB layer and perpendicularly magnetized Co/Ni multilayers. From the ferromagnetic resonance under DC bias current application, we observed a significant linewidth modulation in the FeB layer attributed to the charge to spin conversion generated from Co/Ni multilayers. In-plane angular dependence and the magnetization polarity dependence of the linewidth modulation reveal that two types of charge to spin conversion with different symmetry coexist in the single Co/Ni multilayers.

The use of bare Reduced Activation Ferritic Martensitic (RAFM) steels has been proposed for the first wall in a fusion reactor. Thus, it is necessary to understand the erosion and surface morphology changes under direct and simultaneous hydrogen and helium implantation of RAFM steels under fusion-relevant condition. Experiments were performed at ion energies of ∼1 keV over the temperature range of 500–900 K, consistent with the anticipated operating conditions of the blanket region. The irradiation fluence was 1 × 10 24 m −2 and the He% in the ion beam was 0.5%. Mass loss was measured before and after irradiation to determine erosion. Surface morphology changes were observed by SEM/FIB. RBS was used to quantify the near surface W concentration. From SEM images, surface roughening was observed at T > 750 K and complex surface structures formed with peak-to-peak variation in the ∼μm range. Mass loss increased with increasing surface roughening but the loss for simultaneous hydrogen-helium case was systematically higher compared to hydrogen-only case. A corresponding lower surface W concentration was measured for the simultaneous case, indicating Helium has an important role in W surface enrichment process.

More and more attention is turned to using particular physical systems for innovative computational schemes. For example, an array of synchronized oscillators can be used to solve unconventional, computationally hard problems. Here the authors demonstrate synchronization of spin-transfer-torque nano-oscillators via long-range Oersted magnetic field coupling. This coupling scheme presents the advantage of engineering asymmetric coupling between any two oscillators, which would mimic different biological neural networks. Also, the phase as well as the strength of the coupling can be varied, allowing access to the nonlinear dynamical regime.

International audience; With their very rich static and dynamical properties, magnetic vortex dynamics excited by a spin polarized current represent not only a model system to study the physical mechanisms of spin transfer phenomena but could also give birth to a new generation of multi-functional microwave spintronic devices [1]. The key property of spin-torque nano-oscillators (STNOs) is their high nonlinearity [2] which gives rise to manifold phenomena such as injection locking to an external rf signal [3], [4] or synchronization of multiple STNOs [5]-[7]. On the other hand, their large nonlinearity causes the oscillator's very poor spectral coherence and leads to a coupling between amplitude and phase noise [8]. While the noise distribution for offset frequencies far from the carrier frequency is reasonably well understood [8] and described by the general nonlinear autooscillator theory [2], low frequency noise remains under investigation as it limits the frequency stability of the oscillator. Extensively studied in GMR and TMR sensors [9]-[12], this work addresses the low frequency noise of a TMR-based spin-torque vortex oscillator in the regime of large amplitude steady oscillations. In detail, we present a precise experimental study of the TMR-based spin-torque vortex oscillator's low frequency noise, which remains poorly investigated for STNOs in the regime of large amplitude steady oscillations, as we propose here. The measured STNO's magnetic tunnel junction layer stack of PtMn/CoFe/Ru/ CoFeB/CoFe/MgO/FeB/MgO/Ta/Ru was realized by sputter deposition and nanopillar devices of 100-600nm were nanofabricated. The devices have a free running frequency from 100 MHz to 1 GHz depending on the diameter and the applied field value, with an integrated power of up to a few μW and a linewidth of typically ~100 kHz. In complement to the experimental measurements, we have also developed a phenomenological theory aiming to investigate the low frequency flicker noise in these vortex-STNOs. Starting from the corresponding nonlinear Langevin equations and a colored noise distribution, we find additional noise contributions to the white noise power spectral densities. This also gives an additional coupling term between amplitude and phase noise. Noteworthy, we find that this prediction agrees well to our experimental results of the gyrotropic mode's low frequency noise (Fig. (a)). Furthermore, we analyze the noise dependence on the control parameter (the operating dc current) and the oscillator's active magnetic volume, reflected by the Hooge-formula for TMR sensors [12] and the oscillator's nonlinearity itself (Fig. (b)). S.W. acknowledges financial support from Labex FIRST-TF. EU FP7 grant (MOSAIC No. ICT-FP7-8.317950) is also acknowledged for support.

The concept of spin-torque-driven high-frequency magnetization dynamics, allows the potential construction of complex networks of non-linear dynamical nanoscale systems, combining the field of spintronics and the study of non-linear systems. In the few previous demonstrations of synchronization of several spin-torque oscillators, the short-range nature of the magnetic coupling that was used has largely hampered a complete control of the synchronization process. Here we demonstrate the successful mutual synchronization of two spin-torque oscillators with a large separation distance through their long range self-emitted microwave currents. This leads to a strong improvement of both the emitted power and the linewidth. The full control of the synchronized state is achieved at the nanoscale through two active spin transfer torques, but also externally through an electrical delay line. These additional levels of control of the synchronization capability provide a new approach to develop spin-torque oscillator-based nanoscale microwave-devices going from microwave-sources to bio-inspired networks., The spintronics based complex network is promising for next generation computing systems but hampered by short-range spin-wave coupling. The authors make progress by achieving long range and tunable mutual synchronization of two spin-torque oscillators with improved emission power and signal linewidth.

Y. Aratake, K. Marutsuka, K. Kiyoyama, T. Kuribayashi, T. Miyamoto, K. Yakushiji, S. Ohno, Y. Miyake, T. Sakaguchi, T. K. Kobayashi, A. Okayama, K. Tamura and E. Ohno EMMPRIN (CD147) expression and differentiation of papillary thyroid carcinoma: implications for immunocytochemistry in FNA cytology Objective: Extracellular matrix metalloproteinase inducer (EMMPRIN) and its induced matrix metalloproteinases (MMPs) play a crucial role in tumour progression, invasion and metastasis. EMMPRIN expression has been demonstrated in several tumours, but its expression profile in thyroid cancer remains unclear. Methods: We evaluated the expression profile of EMMPRIN at various stages of differentiation of thyroid carcinoma, including 20 cases of well-differentiated papillary carcinoma (WDPC), 15 cases of papillary carcinoma with a poorly differentiated carcinoma component (PC/PDC) and four cases with an undifferentiated carcinoma (UDC) component, using paraffin-embedded sections for immunohistochemical stains. Also, we used 32 fine needle aspiration cytology and imprint smears from the same cases for immunocytochemical stains. The staining results were evaluated with a scoring system. Results: Immunohistochemical staining showed that EMMPRIN expression was absent or weak in almost all WDPC specimens, whereas it was moderate or strong in PDC and UDC components. In tumours that showed a gradual morphological transformation from WDPC to PDC components, the expression of EMMPRIN was progressively stronger from the areas of WDPC to those of PDC. WDPC, PC/PDC and UDC had expression scores of 4.9, 45.0 and 245.7, respectively. Results of immunocytochemical staining showed almost the same staining profile as those of immunohistochemical staining. The cytological atypia of EMMPRIN-positive cells was greater than that of negative cells. Conclusion: These results indicated that EMMPRIN expression correlates significantly with the degree of dedifferentiation of thyroid carcinoma. This study demonstrates the feasibility of expression of EMMPRIN using fine needle aspiration samples. Therefore, immunocytochemical analysis of EMMPRIN may be a novel aid to evaluate the differentiation of thyroid carcinoma.

An Fe-based perpendicular alloy with small damping constant was applied to an MTJ storage layer and small switching current of 9 μA was obtained for a write current width of 5 ms. The efficiency of spin transfer torque writing was proved to be higher than those for in-plane MTJs. The estimated Ic for the MTJ with 50 nsec pulse width is lower than 20 μA and smaller than the drive currents of CMOS transistor at Gbits density.

Thermal stability of magnetization in a nano-magnet is an important issue for the retention of stored data in a magnetic random access memory based on spin-torque switching. Within the thermal activation model, the distribution of the switching current of spin-torque switching (Ic) at finite temperature is roughly proportional to the inverse of the thermal stability parameter (Δ). In this paper, we present a new method for evaluating Δ from the distribution of Ic. This method can give us correct Δ at any given pulse width.

The perpendicular magnetic anisotropy of sputtered CoFeB thin films covered by MgO was investigated by vibrating sample magnetometry. Three different CoxFe80-xB20 alloys were studied. Under out-of plane magnetic field, the saturation field was found to increase with increasing the Co content. The magnetization and interface anisotropy energy were obtained for all samples. Both showed a marked dependence on the MgO overlayer thickness. In addition, their variations were found to be non-monotonous as a function of the Co concentration.

Spin-RAM technologies for operation speed faster than 30 ns, memory capacity larger than 1 Gbits and practically infinite read/write endurance have been developed by using magnetic tunnel junctions with perpendicular magnetization layers. Combination of Spin-RAM and power-gating technology will enable ultra low power computer called Normally-Off Computer.

A growing number of studies indicate the importance of the lysyl oxidase family in the promotion of epithelial neoplasms towards their more aggressive forms. However, the role of individual family members in carcinoma progression has yet to be ascertained. In this study, we analyzed LOXL2 expression in malignantly transformed MCF-7 and normal MCF-10A mammary epithelial cell line clones stably transduced with LOXL2 in vitro, and in normal and cancerous breast tissue samples in vivo. We found LOXL2 to be catalytically active in both MCF-7 and MCF-10 clones. LOXL2 overexpression promoted a more mesenchymal morphology in both cell types, but LOXL2-induced increase in migratory ability could only be established in MCF-7 clones. We demonstrated altered localization of the LOXL2 protein in breast cancer tissue compared to normal mammary tissue, and altered localization and processing of LOXL2 protein in breast cancer cell lines compared to normal cell lines, which may allow LOXL2 to interact with different intra and extracellular components during tumor progression. Results support the role of LOXL2 in selectively promoting a metastatic phenotype in breast tumor cells. Additional data suggest epigenetic molecular mechanisms in tumor specific regulation of LOXL2 expression that could be explored as a molecular target in the prevention of breast cancer progression.

AIM: To evaluate a new approach to the differentiation of the right and left ribs, the vertical displacement sign, and to compare its efficacy with the big rib sign. MATERIALS AND METHODS: One hundred and nine lateral chest radiographs that clearly showed both the gastric air bubble sign and the cardiac silhouette sign were retrospectively reviewed by two radiologists. Each study was evaluated by consensus. Each radiograph was assessed for suitability of reading with each technique. Suitable radiographs were then reviewed using both the big rib sign and vertical displacement sign independently. RESULTS: Applicability of the vertical displacement sign [107 of 109 (98%)] was greater than that of the big rib sign [95 of 109 (87%)] ( P = 0.0017). The accuracy of the vertical displacement sign [105 of 107 (98%)] was higher than that of the big rib sign [74 of 95 (78%)] ( P CONCLUSION: The vertical displacement sign seems to be a reliable technique for the differentiation of right and left ribs on the lateral chest radiograph and can be used as a complementary technique when the big rib sign is not applicable.Kurihara, Y. (1999) Clinical Radiology 54 , 367–369.

The purpose of this study was to assess radiographic and computed tomography (CT) findings of the vertical fissure.We assessed whether the vertical fissures appeared as a fine linear shadow or as a linear edge with lateral opacity and medial lucency on chest radiographs. The CT scans were evaluated for the presence of volume loss in the lower lobes and for the presence of a portion of the fissure that is orientated tangential to the X-ray beam.We observed vertical fissures in six patients. CT studies revealed volume loss in the lower lobes in all patients and showed the presence of a portion of the fissure that is orientated tangential to the X-ray beam in only two patients whose vertical fissures were not associated with lateral opacity and medial lucency on chest radiographs.We believe that the vertical fissure is closely related to volume loss in the lower lobe and represents the edge of the anterobasal segment of a major fissure or a portion of the fissure that is orientated tangential to the X-ray beam, with or without lateral opacity and medial lucency.

Deuterium and helium retention in Japanese reduced activation ferritic martensitic (RAFM) steel (F82H) under simultaneous D–He irradiation at 500, 625, 750, and 818 K was studied. This study aims to clarify tritium retention behavior in RAFM steels to assess their use as plasma facing materials. The irradiation fluence was kept constant at 1 × 1024 D m−2. Four He desorption peaks were observed with He retention greatest at 625 K. At T > 625 K a monotonic decrease in He retention was observed. At all temperatures a systematic reduction in D retention was observed for the simultaneous D–He case in comparison to D-only case. This suggests that He implanted at the near surface in RAFM steels may reduce the inward penetration of tritium in RAFM steels that would result in lower tritium inventory for a given fluence.

The (111) facet faces on the seed cone of the [100] silicon single crystals grown by MCZ and CZ methods were characterized on an atomic scale by using X-ray CTR scattering. The natural (111) facet face of the MCZ single crystal was found to have a roughness of about three layers. This roughness is only very slightly inferior in comparison with that of the mechano-chemically polished (111) surface of a silicon wafer which has a roughness of two layers and is the flattest surface we have ever investigated. However, the (111) facet face of the usual CZ single crystal was so poor that the flatness could not be estimated. The effect of magnetic field on the crystal growth is discussed on the basis of these facts.

The ribs are essential structures of the osseous thorax and provide information that aids in the interpretation of radiologic images. Techniques for making precise identification of the ribs are useful in detection of rib lesions and localization of lung lesions. The big rib sign and the vertical displacement sign can be used to differentiate the right and left ribs on lateral chest radiographs. The clavicle, the xiphoid process, and the sternal angle may be used as anatomic landmarks for rib counting on computed tomographic scans. For rib counting on lateral chest radiographs, the sternal angle or the 12th rib may be used. Anatomic rib variants include developmental deformities, cervical rib, and short rib and may mimic true rib diseases. Detection of thoracic deformities such as funnel chest (pectus excavatum) and barrel-shaped thorax requires an awareness of the strong correlation between the transverse appearance of the thorax and costal shape. Shadows around the rib cage (eg, rib companion shadows, sharp lines along the lower margin of the ribs, rib overlying shadows) may mimic pleural and extrapleural disease on frontal chest radiographs. It is imperative that the radiologist be familiar with normal rib anatomy, normal rib variants, and the radiologic appearance of the ribs to prevent misdiagnosis.

The separation measurements of a bulk lifetime υo, front and back surface recombination velocities S0, Sw have been investigated for both 620 μm and 1.08 mm thick Si wafers with various surface treatments. The separation was made by applying bisurface photocoductivity decay method to the photoconductivity decay curves measured by 500 MHz microwave reflection under the bias light illumination. The bulk lifetime and the surface recombination velocities have been determined, respectively, to be 624–659 μs and 18.4–66.1 cm/s for the oxidized sliced-surface and 6285 cm/s for the sliced surface. And they have been also determined, respectively, to be 412–422 μs and

The experiment on the effects of green manure application on the yield and growth of Satsuma orange trees has been conducted since 1946 at Ehime Fruit Tree Experiment Station, Five experi-mental plots have been set up in the terraced orchard on diluvial soil. The total amount of each element (nitrogen, phosphorous and potassium) applied was same in all plots. In the “100% green manure” plot, green manure alone was applied every year, lupin or broad bean being applied in April and soybean in September. The “0% green manure” plot was applied with chemical fertilizers alone with no green manure. In the 75, 50 and 25% green manure plots, the amounts of green manure applied were the designated percents as much as that applied to the “100% green manure” plot, and the rests were supplemented with the chemical fertilizers. The Satsuma orange trees on trifoliate orange were 25 years old in 1946 when the experiment was started. Each plot was con-sisted of six trees. 1. The yield in the 0% green manure plot was larger than that in the 100% green manure plot for the first three years (1946 to 48), nearly equal to the latter for the following three years (1949 to 51), and then exceeded by the latter since 1952. The 25%, 50%, and 75% plots situated between the 0% and 100% plots in their yields. Since 1953, the yield of 25% plot approached to that of the 0% plot, and the 75% plot to 100% plots. The trees. in the 0% plot have gradually lost their vigor, and since 1957 they have been so exhausted that they could hardly be used in the experiment. The yield of the 50% plot has been intermediate between those of the 100% and 0% plots. 2. Measurements of size and shape of fruits for 7 years, 1950 to 56, showed that the more the green manure was applied, the larger the fruit size and the flatter the fruit shape. Fruit growth during July to November was better in the 100% plot than. in the 0% plot. 3. The experiments on fruit storage conducted in 1948 to 53 revealed that the percentage of storage loss due to molds was less in the plots receiving larger amounts of green manure. 4. Tree volume and trunk circumference in 1960 were larger in the plots receiving larger amount of green manure, showing the same tendency as, the results on the yields for 1956 to 59.

In cases of gestational choriocarcinoma, the period from antecedent pregnancy to the onset of the disease (latent period) is watched as a risk factor. When this period was calculated in about 106 cases collected, a period of more than 2 years was found in 8 cases. Therefore, concerning these 8 cases, investigation was made into the chief complaint, the kind of antecedent pregnancy, clinical stage classification, hCG value on diagnosis, histological classification and prognosis. As to the kind of antecedent pregnancy, 7 cases out of 8 were hydatidiform moles (87.5%). However, in 98 cases with a latent period within 2 years, the number of cases of mole antecedent was 54 (55.1%). With the lengthening of the latent period the incidence of antecedent hydatidiform mole tended to increase. Moreover, in the histological classification, particularly in our CPV classification, 7 cases were seen to be P type or V type. In the long-term cases over 2 years a high degree of histological malignancy was observed compared with those of latent periods of less than 2 years.

As a method to elucidate the histogenesis of this tumor, it is necessary to make a comparative study of the morphological relation between the histopathology of the tumor and the mother tissue which is considered to be the origin of the tumor. Therefore, as already reported, since we induced the yolk sac tumor by treating the fetal membrane of pregnant rats with carcinogenic agents, we have comparatively studied the tumor tissue and the fetal membrane, which is considered the mother tissue, to elucidate the histogenesis by seeking the similarity between them and the common features and obtained the following conclusions. First, the presence of PAS positive non-glycogenic granules was noted in both cytoplasms, and then the localization of AFP was confirmed in both cytoplasms also in the study with a fluorescence antibody method using anti-rat AFP antibody. Further, in the observation at the level of electron microscopy, as findings common to both, we noted the presence of round homogeneous non-structural substance and characteristically developed r-ER, and, on the other hand, immature nuclei containing thread-like nucleolonema, considered characteristic to germ cell tumor. From the above results, this induced tumor was considered to have developed from the rat fetal membrane as mother tissue.

The ability of isolated skin and kidney cells to activate allogeneic lymphocytes in vitro was studied in the MHC-identical and incompatible rat strains. The preparation of these cells and optimal culture conditions were summarized. 3H-thymidine uptake was strongest with skin epidermal cells and weakest with kidney cells. The results obtained from fractionated cells indicated that both Langerhans (Ia positive) and other cells (Ia negative) of the skin epidermis stimulated lymphocytes equally well and that only glomerulus and whole kidney cells stimulated, whereas cells fom the medulla and cultured epithelium failed to do so. It was suggested that skin epidermal cells possess lymphocyte-activating antigens other than Ia antigens that may be responsible for MHC-identical graft rejection. The weaker reaction by kidney cells and the limited localization of lymphocyte-activating determinants suggest that kidney cells may not express specific alloantigens detectable by the procedure employed; these cells obviously carry only a limited amount of Ia antigens.

We experimentally demonstrate that large amplitude magnetic vortex gyrations can be parametrically excited by the injection of radio-frequency (rf) current at twice the natural frequency of the gyrotropic vortex-core motion. The mechanism of excitation is based on the parallel pumping of vortex motion by the rf orthoradial field generated by the injected current. Theoretical analysis shows that experimental results can be interpreted as the manifestation of parametric amplification when the rf current is small, and of parametric instability when the rf current is above a certain threshold. By taking into account the energy nonlinearities, we succeed to describe the amplitude saturation of vortex oscillations as well as the coexistence of stable regimes.