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混合高细胞-筛状桑葚亚型（TCV-CMV）是甲状腺乳头状癌（PTC）罕见亚型。仔细的细胞学、组织学观察及特异的免疫组织化学染色有助于作出正确诊断。高细胞亚型PTC（TCV-PTC）是侵袭性亚型之一，术前及术中准确诊断有助于手术方案的合理选择及预后判断。筛状桑葚亚型PTC（CMV-PTC）有独特的病理、免疫组织化学及分子特征，也是遗传性甲状腺癌的典型亚型，可提示临床医师进行结肠镜检查、遗传咨询和家庭成员筛选。CMV-PTC多数预后较好，当出现不良预后指征时，警惕其复发及转移可能。.

Effects of root treatment with 5-aminolevulinic acid (ALA) on leaf photosynthesis in strawberry (Fragaria ananassa Duch.) plants were investigated by rapid chlorophyll fluorescence and modulated 820 nm reflection using 3-(3,4-dichlorophenyl)-1,1-dimethyl urea (DCMU) and methyl viologen (MV). Our results showed that ALA treatments increased the net photosynthetic rate and decreased the intercelluar CO2 concentration in strawberry leaves. Under DCMU treatment, trapping energy for QA reduction per PSII reaction center increased greatly, indicating DCMU inhibited electron transfer from QA −. The maximum photochemical efficiency of PSII (Fv/Fm) decreased under the DCMU treatment, while a higher Fv/Fm remained in the ALA-pretreated plants. Not only the parameters related to a photochemical phase, but also that one related to a heat phase remained lower after the ALA pretreatment, compared to the sole DCMU treatment. The MV treatment decreased PSI photochemical capacity. The results of modulated 820 nm reflection analysis showed that DCMU and MV treatments had low re-reduction of P700 and plastocyanin (PSI). However, the strawberry leaf discs pretreated with ALA exhibited high re-reduction of PSI under DCMU and MV treatments. The results of this study suggest that the improvement of photosynthesis by ALA in strawberry was not only related to PSII, but also to PSI and electron transfer chain.

Conventional silicon-based devices are approaching the scaling limits toward super miniaturization, where the quantum size effect naturally emerges with increasing importance. Exploring the quantum size effect may provide additional functionality and alternative architectures for information processing and computation. Scanning tunneling microscopy/spectroscopy is an ideal tool to explore such an opportunity as it can construct the devices in an atom-by-atom fashion and investigate their morphologies and properties down to the atomic level. Utilizing nanocorrals as examples, the quantum size effect is demonstrated to possess the great capability in guiding the adatom diffusion and the self-assembly, controlling the statistical fluctuation, tuning the Kondo temperature, etc. Besides these fundamentals, it also shows strong potential in logic operations as the basic logic gates are constructed.

We address the long-term controversy on the fundamental question of the role of the surface state on the Kondo effect with Co adatoms on a Ag(111) surface. The width of the Kondo resonance oscillates with the same period of half Fermi wavelength of the surface state. But the amplitude increases for a Co adatom placed next to another Co adatom, at the vicinity of a step edge, and quantum confined within nanocorrals. A greater than three times enhancement of the resonance width can be achieved when quantum confinement is introduced. The experimental results are described quantitatively utilizing an analytical model where the contributions of the bulk and surface states are weighted by their exchange values with the magnetic impurity. These findings clarify the role of the surface state on the Kondo effect and pave a pathway to tailor the Kondo effect via quantum confinement of the surface state.

We report a method to switch both the circulation and polarity of magnetic vortices in a controlled manner within a nanosecond utilizing micromagnetic simulations. The controllable switching is achieved with the combination of two different types of magnetic field pulses on submicron permalloy disks with heptagonal shape. When a magnetic field pulse of ~100 mT is applied along one of the edge directions of the heptagon, the circulation of the vortex can be manipulated according to the pulse direction. When a pair of pulses with a few tens of mT in magnitude and relative delay of about 100 ps is applied in orthogonal directions, the polarity can be further controlled without influencing the circulation. The different magnitude of switching fields allows for the combination of both types of pulses in the control of both the circulation and polarity of magnetic vortices. The switching mechanism and the controlling parameters for disks with diameters of 500 and 700 nm are discussed.

Utilizing a novel method with the resonance frequency of a LC circuit, we measured the superconducting anisotropy of single crystals of an Fe-based superconductor FeSe with applied magnetic field up to 16 T. We found that the temperature dependence of the upper critical field H c2 (T) of FeSe coincides with the Werthamer-Helfand-Hohenberg (WHH) model when taking the Maki parameter α into consideration, suggesting an important role played by spin-paramagnetic effect in suppressing the superconductivity. When temperature T → 0, the values of H c2,≈c (0) and H c2,≈ab (0) derived from the WHH fitting are close to and fall within the range of the Pauli limit, for field H 0 applied parallel to the c-axis and to the ab-plane, respectively. As compared with other typical iron-based high-T c superconductors, lower values of H c2 (0) and higher superconducting anisotropy Γ(0) were observed in FeSe. © 2019 Author(s). The work at Yangzhou Univ. was supported by Natural Science Foundation of China (NSFC) grant # 61474096 and by NSF of Jiangsu grant # BK20180889, and at Chinese Academy of Sciences by NSFC grants # 51477167 and 41527802. D.A.C. thanks supports by the program 211 of the Russian Federation Government (RFG), agreement 02.A03.21.0006 and by the Russian Government Program of Competitive Growth of Kazan Federal Univ. A.N.V. thanks supports by Russian Foundation for Basic Research Grant No. 17-29-10007, by the Ministry of Education and Science of the Russian Federation in the framework of Increase Competitiveness Program of NUST MISiS (Grant No. K2-2017-084), and by Act 211 of RFG, agreements 02.A03.21.0004, 02.A03.21.0006, and 02.A03.21.0011.

Carbohydrates have drawn considerable interest from researchers recently due to their affinity for CO2. However, most of the research in this field has focused on peracetylated derivatives. Compared with acetylated carbohydrates, which have already been studied in depth, methyl D-glucopyranoside derivatives are more stable and could have additional applications. Thus, in the present work, ab initio calculations were performed to elucidate the characteristics of the interactions of methylglucoside derivatives with CO2, and to investigate how the binding energy (ΔE) is affected by isomerization or the introduction of various acyl groups. Four methyl D-glucopyranosides (each with two anomers) bearing acetyl, propionyl, butyryl, and isobutyryl moieties, respectively, were designed as substrates, and the 1:1 complexes of a CO2 molecule with each of these sugar substrates were modeled. The results indicate that ΔE is mainly influenced by interaction distance and the number of negatively charged donors or interacting pairs in the complex; the structure of the acyl group present in the substrate is a secondary influence. Except in the case of methyl 2-O-acetyl-D-glucopyranose, the ΔE values of the α- and β-anomers of each methylglucoside were found to be almost the same. Therefore, we would expect the CO2 affinities of the four derivatives studied here to be as strong as or even stronger than that of peracetylated D-glucopyranose. Graphical Abstract The binding energy between methyl D-glucopyranoside derivatives with various substituted acyl groups and CO2 are evaluated by ab initio calculations. The strong interaction between these methyl dglucopyranoside derivatives and CO2 showed the potential of their application for CO2 capture.

Low dimensional nanostructures have attracted attention due to their rich physical properties and potential applications. The essential factor for their functionality is their electronic properties, which can be modified by quantum confinement. Here the electronic states of Gd atom trapped in open Fe corrals on Ag(111) were studied via scanning tunneling spectroscopy. A single spectroscopic peak above the Fermi level is observed after Gd adatoms are trapped inside Fe corrals, while two peaks appear in empty corrals. The single peak position is close to the higher energy peak of the empty corrals. These findings, attributed to quantum confinement of the corrals and Gd structures trapped inside, are supported by tight-binding calculations. This demonstrates and provides insights into atom trapping in open corrals of various diameters, giving an alternative approach to modify the properties of nano-objects.

Utilizing open Fe nanocorrals built by atom manipulation, we demonstrate self-regulated Gd atom trapping in open quantum corrals. The number of Gd atoms trapped is exactly determined by the diameter of the corral. The quantization can be understood as a self-regulating process, arising from the long-range interaction between Gd atoms and the open corral. We illustrate with arrays of open corrals that such atom trapping can suppress unwanted statistical fluctuations. Our approach opens a potential pathway for nanomaterial design and fabrication with atomic-level precision.

We present the study of the quantum tunneling through a vertical two-barrier structure sandwiching a graphene nanoribbon quantum object. Scanning tunneling microscopy measurements of the graphene nanoribbon show staircase I-U characteristics and oscillating dI/dU spectra. To identify the physical origin of the observed effect, we varied the tunneling resistance of the tip-ribbon junction and found a tip-to-ribbon distance dependent oscillating period change. Together with the numerical analysis, we confirm that the resonances in the spectroscopy arise from the Coulomb blockade effect. The study of the Coulomb blockade effect in graphene nanoribbons may be of potential usages for the fabrication of superthin quantum dot devices.

Gd atom diffusion in 30-nm-diameter Fe quantum corrals is studied utilizing scanning tunneling microscopy and kinetic Monte Carlo (KMC) simulations. The Gd adatom probability distribution inside the corral forms several trajectories and is closely related to oscillations of the local density of states at the Fermi level, as revealed by spectroscopy measurements. With increasing coverage, the Gd adatoms form a ringlike structure within the vicinity of the quantum corrals. The results are explained with KMC calculations utilizing experimentally determined long-range interactions and quantum confinement. The findings demonstrate that the diffusion of Gd adatoms is significantly influenced by the quantum corrals and that novel quantum ring structures can be created via control of the coverage.

A Skyrmion crystal typically arises from helical spin structures induced by the Dzyaloshinskii-Moriya interaction. Experimentally its physical exploration has been impeded because it is a rarity and is found only within a narrow temperature and magnetic field range. We present a method for the assembly of a two-dimensional Skyrmion crystal based upon a combination of a perpendicularly magnetized film and nanopatterned arrays of magnetic vortices that are geometrically confined within nanodisks. The practical feasibility of the method is validated by micromagnetic simulations and computed Skyrmion number per unit cell. We also quantify a wide range in temperature and field strength over which the Skyrmion crystal can be stabilized without the need for any intrinsic Dzyaloshinskii-Moriya interactions, which otherwise is needed to underpin the arrangement as is the case in the very few known Skyrmion crystal cases. Thus, our suggested scheme involves a qualitative breakthrough that comes with a substantial quantitative advance.

Utilizing scanning tunneling microscopy, we investigate the coverage- and temperature-dependent morphology evolution of submonolayer Fe on Ru(0001) near the surface alloying temperature. Submonolayer Fe deposited on Ru(0001) at room temperature grows in the three-dimensional island format. The morphology is investigated after annealing at various temperatures. With annealing around 900 K, large compact islands are divided into small pieces by triangular vacancy islands and labyrinthine antistripes. The width of the antistripes increases with increasing temperature, in sharp contrast with other systems where the opposite behavior was commonly found. The observed anomaly can be attributed to simultaneous surface alloying and amorphization during the annealing process.

Available sensorless speed control strategies of doubly fed induction generator (DFIG) usually fail around the synchronous speed or limited by the operation mode (motor or generator). A novel control strategy is proposed in this paper. It uses the stator flux magnetizing current to estimate the rotor position and speed. This strategy works properly in the whole speed range. The principle of the speed and position estimation is explained and the corresponding speed regulation system is built. The proposed control strategy is examined in Simulink. The simulation results demonstrate the feasibility of the stator flux magnetizing current based rotor position and speed estimation as well as the control behaviors of the speed regulation system.

We present a micromagnetic study on the eigen excitations of an artificial skyrmion crystal, which has been experimentally confirmed to be stable at room temperature without the need of any Dzyaloshinsky-Moriya interaction (DMI). Three in-plane rotational modes and one breathing-type mode are identified. We find the intrinsic origin of the dynamics of skyrmion crystal is the nontrivial magnetic texture instead of DMI. And the rotational direction of a skyrmion is solely determined by the sign of the skyrmion number, irrespective of its circulation sense, evidencing the topological nature of the magnetic skyrmion.

Step-edge guided Gd one-dimensional atomic strings on Ag(111) surface are studied by scanning tunneling microscopy and spectroscopy at low temperature. Spectroscopy measurements show a characteristic peak, 65 meV above Fermi level in sharp contrast with tight-binding calculations of a string on a flat terrace. Good agreement can be obtained when the step edges are included in the calculations, revealing their roles on the electronic spectra of the self-assembled strings guided by step edges. The results are further confirmed by the spectroscopy study of Fe strings on a flat terrace and near step edges constructed by atomic manipulation.

We present the width dependent study of edge distribution of graphene nanoribbons unzipped from multi-wall nanotubes. The partial unzipping of the carbon nanotubes yields a mixture of carbon nanotubes and nanoribbons. Comparing atomic resolution images of scanning tunneling microscopy with the lattice of graphene, the edge structures of nanoribbons are identified. Below 10 nm, the edges are closer to armchair type. Above 20 nm, the ribbons prefer to have edges close to zigzag type. In between, a more random distribution of the edges is found. The findings are of potential usages for the edge control in graphene nanoribbon based applications.