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The emergence and development of multimodal imaging techniques, such as optical coherence tomography, fundus autofluorescence and adaptive optics, make it much easier to differentiate reticular pseudodrusen (RPD) from other fundus lesions. It is of great significance to understand the imaging characteristics of RPD observed with multimodal imaging techniques. This article reviews the formation mechanism and multimodal imaging characteristics of RPD, so as to provide help for better identification of RPD and assessment of the development and prognosis of the disease.随着眼底相干光层析成像术、自发荧光、自适应光学等影像技术的出现和发展，网状假性玻璃膜疣（RPD）的组织形态和分布特点也更明晰。熟知多模式影像中RPD的表现特征对于疾病的鉴别诊断具有重要意义。本文对RPD的形成机制及多模式影像表现的相关研究进行综述，以期为准确地识别RPD和评估疾病的进展预后提供帮助。.

为全面提升高血压患者规范化筛查及诊断与治疗水平，实现高血压临床实践标准化，提高中国高血压防控水平，国家心血管病中心、中国医师协会、中国医师协会高血压专业委员会、中华医学会心血管病学分会、海峡两岸医药卫生交流协会高血压专业委员会联合发起制定《中国高血压临床实践指南》，中国医学科学院循证评价与指南研究创新单元、兰州大学健康数据科学研究院、中华医学会杂志社指南与标准研究中心、GRADE兰州大学中心提供了方法学支持。.

The proband was an 8-year-old boy, complaining of progressively decreased vision in both eyes for 3 years. The electroretinogram was characterized by supernormal rod response. While the responses of the rod and cone system were reduced, the amplitudes of dark-adapted electroretinogram responses at a high intensity were supernormal. A homozygous non-frameshift deletion variant c.1002-1004del (p. L335del) in KCNV2 was found by the Next Generation Sequencing using a custom designed panel. His father was a heterozygous carrier of this variant. In silico analysis indicated the variant was harmful. The proband was diagnosed as cone dystrophy type 3B which also known as cone dystrophy with supernormal rod response.先证者为8岁男性患儿，双眼视力进行性下降3年，视网膜电图表现为独特的闪光视网膜电图波形，视杆和视锥系统反应下降；但暗适应状态高刺激强度时，视锥和视杆系统混合反应振幅“超正常”。基于靶向捕获（panel）的二代测序检测显示患儿KCNV2基因发生纯合非移码缺失变异c.1002-1004del（p.L335del），患儿父亲携带该杂合变异。经生物信息分析，该变异具有致病性，诊断为视锥细胞营养不良3B型，即视锥细胞营养不良伴超正常视杆系统反应。.

A nanolaminated surface layer was produced on interstitial-free steel by surface mechanical rolling treatment. While the microstructure showed relatively high thermal stability during annealing at 500°C, significant grain boundary (GB) migration occurred in the nanolaminated surface layer during chromizing at the same temperature. GB diffusion of Cr was observed under the Harrison B-type regime in the chromized surface layer. The accelerated GB migration was discussed to be influenced by enhanced GB energy and mobility due to the GB diffusion and enrichment of Cr in nanolaminated structures. Meanwhile, the high stresses introduced during sample preparations also enhance the coarsening kinetics. Different from enhanced thermal stability by regular GB segregation, GB enrichment of Cr due to fast GB diffusion from a Cr-coating can accelerate the GB migration in nanolaminated IF steel.

Root-lesion nematodes (Pratylenchusspp.) are a group of economically important pathogens that have caused serious economic losses in many crops. In 2019, root-lesion nematodes were recovered from tomato (Solanum lycopersicum) root samples collected from Sichuan Province, People's Republic of China (PRC). Extracted nematodes were disinfected, and one individual female was cultured on a carrot disc for propagation at 25 °C by parthenogenesis and designated the SC isolate. Afterwards, the isolate was identified on the basis of morphometric and molecular markers. Both morphometric characters and molecular analysis of the internal transcribed spacer region gene (ITS) of ribosomal DNA, the D2-D3 expansion region of the 28S rDNA gene and the mitochondrial cytochrome oxidase I (mtDNA-COI) gene revealed that the species of root-lesion nematode wasPratylenchus scribneri. The Bayesian tree inferred from the ITS rDNA, 28S rDNA and mtDNA-COI gene sequences also showed that this isolate formed a highly supported clade with otherP. scribneriisolates. The pathogenicity of the root-lesion nematode SC isolate on tomato was assessed, showing that tomato was a suitable host forP. scribneri. To the best of our knowledge, this is the first report ofP. scribnerion tomato in Sichuan Province, PRC. These are also the first molecular data obtained fromP. scribnerion tomato in the PRC, and the pathogenicity ofP. scribnerito tomato was studied for the first time. This study provides scientific data for the detection, identification and control of tomato root-lesion nematode disease.

阻塞性睡眠呼吸暂停（OSA）引发全身多系统多器官损害，影响全球超10亿人健康，而未经诊断和治疗者高达90%。深度学习作为一项颇受关注的人工智能技术，在耳鼻咽喉头颈外科领域的应用愈来愈广泛，其与多导睡眠信号结合成为睡眠呼吸事件自动检测和OSA辅助诊断研究的热点。本文就近年来相关文献作一综述，以供后续研究参考。.

Electronic properties of FeSe can be tuned by various routes. Here, we present a comprehensive study on the evolution of the superconductivity and nematicity in FeSe with thickness from bulk single crystal down to bilayer ($\sim$ 1.1 nm) through exfoliation. With decreasing flake thickness, both the structural transition temperature $T_{\rm s}$ and the superconducting transition temperature $T_{\rm c}^{\rm zero}$ are greatly suppressed. The magnetic field ($B$) dependence of Hall resistance $R_{xy}$ at 15 K changes from $B$-nonlinear to $B$-linear behavior up to 9 T, as the thickness ($d$) is reduced to 13 nm. $T_{\rm c}$ is linearly dependent on the inverse of flake thickness (1/$d$) when $d\le$ 13 nm, and a clear drop of $T_{\rm c}$ appears with thickness smaller than 27 nm. The $I$-$V$ characteristic curves in ultrathin flakes reveal the signature of Berezinskii-Kosterlitz-Thouless (BKT) transition, indicating the presence of two-dimensional superconductivity. Anisotropic magnetoresistance measurements further support 2D superconductivity in few-layer FeSe. Increase of disorder scattering, anisotropic strains and dimensionality effect with reducing the thickness of FeSe flakes, might be taken into account for understanding these behaviors. Our study provides systematic insights into the evolution of the superconducting properties, structural transition and Hall resistance of a superconductor FeSe with flakes thickness and provides an effective way to find two-dimensional superconductivity as well as other 2D novel phenomena., 8 pages, 6 figures

In order to determine the long-term performance of curved composite girder bridges, a finite element model of a three-span curved continuous composite bridge with a radius of curvature of 75m was established. The stress and deflection of the bridge due to uniform temperature, temperature gradient, shrinkage and creep were obtained with finite element method. The influence of the radius of curvature was further analyzed. Results show that the shrinkage has the greatest influence on the stress and deflection of the bridge. The deflection of side span and the cross-section torsion angle increases by 30% and 38% respectively compared to dead load, and the tensile force of the studs in the negative moment zone increase by 63% under shrinkage. As the radius of curvature increases, the principal tension stress in concrete and torsion angle of the concrete slab decrease by 13% and 45% respectively.

Superconductivity beyond electron-phonon mechanism is always twisted with magnetism. Based on a new field-effect transistor with solid ion conductor as the gate dielectric (SIC-FET), we successfully achieve an electric-field-controlled phase transition between superconductor and ferromagnetic insulator in (Li,Fe)OHFeSe. A dome-shaped superconducting phase with optimal Tc of 43 K is continuously tuned into a ferromagnetic insulating phase, which exhibits an electric-field-controlled quantum critical behavior. The origin of the ferromagnetism is ascribed to the order of the interstitial Fe ions expelled from the (Li,Fe)OH layers by gating-controlled Li injection. These surprising findings offer a unique platform to study the relationship between superconductivity and ferromagnetism in Fe-based superconductors. This work also demonstrates the superior performance of the SIC-FET in regulating physical properties of layered unconventional superconductors.

In order to improve the machining efficiency of engine closed integral impeller, the electrochemical machining (ECM) and electrical discharge machining (EDM) combined technology was proposed. ECM was used to remove the large machining allowance with high efficiency, and then the precision processing was accomplished by EDM. Because the two ends of the vortex channel are large and the middle is narrow, so the special-shaped vortex channel was divided into internal and external flow channels. First of all, based on the problem of flow field diverge and non-uniform in ECM S-03 special stainless steel material, the method of reverse flow ECM external flow channel was proposed. The ECM fixture design of internal and external flow channels was carried out, and the composite electrolyte composition of 5%NaCl+16%NaNO3+4%NaClO3 was obtained. Secondly, the EDM rough and precision machining electrodes were designed and the EDM experiment has done. Finally, the combined ECM and EDM experiment was finished. The experiment result showed that the combined method is feasible for machining closed integral impeller; the machining efficiency is 30% higher than that of EDM alone.

The purpose of this research was to explore whether the expression of carbonic anhydrase 12 (CA12) and the prognosis had a significant relationship in breast cancer patients. A total of 262 breast cancer specimens and 75 normal breast tissue specimens were recruited in this study. The expression of CA12 was detected by immunohistochemistry (IHC), and its correlation with the clinicopathological characteristics of breast cancer patients and their prognosis were further analyzed through standard statistical algorithms. The result of immunohistochemical staining showed that CA12 was detected in both normal breast tissue and breast cancer tissue. Compared to normal breast tissue, CA12 was significant higher expressing in cancer tissues (P=0.009). Statistical analysis showed that the high expression of CA12 in breast cancer tissue was related to estrogen receptor expression level (P

In order to solve the problems of flow field divergence, short circuit, and poor forming precision in electrochemical machining (ECM) large-diameter special-shaped inner spiral tube with pull reverse flow-cathode structure, a pull downstream cathode structure is proposed which has the function of changing working teeth and converging electrolyte flow field. The gap flow field simulation model was established, and then comparing and analyzing the gap flow field between pull downstream cathode model and the pull reverse flow cathode model. The simulation results show that pull downstream cathode structure is better than pull reverse flow-cathode structure in the gap electrolyte velocity, pressure, and streamline under the condition of 15 m/s electrolyte inlet velocity and electrolyte outlet pressure with atmospheric pressure. We also analyzed the stress and displacement of these two different cathode structures. The simulation results show that the maximum stress is 0.350 MPa and the maximum displacement is 4.275 × 10−5 mm with pull downstream cathode. However, the maximum stress of traditional pull reverse flow cathode is 0.428 MPa and the maximum displacement is 5.6355 × 10−5 mm. Finally, under the conditions of 12 V, 20 mm/min cathode feed speed, 15 wt% NaCl electrolyte with temperature 30 °C, and inlet pressure 1.5 MPa, the 2000 mm qualified sample was machined stably and reliably by pull downstream cathode. It indicates that it is feasible to machining large-diameter special-shaped inner spiral tube with the new pull downstream cathode structure.

As one of the most fundamental physical phenomena, the anomalous Hall effect (AHE) typically occurs in ferromagnetic materials but is not expected in the conventional superconductors. Here, we have observed a giant AHE in kagome superconductor CsV3Sb5 with transition temperature (Tc) of 2.7 K. The anomalous Hall conductivity reaches up to 2.1*10^4 {\Omega}-1 cm-1 which is larger than those observed in most of the ferromagnetic metals. Strikingly, the emergence of AHE exactly follows the higher-temperature charge-density-wave (CDW) transition with TCDW ~ 94 K, indicating a strong correlation between the CDW state and AHE. Furthermore, AHE disappears when the CDW transition is completely suppressed at high pressure. The origin for AHE is attributed to enhanced skew scattering in CDW state and large Berry curvature arose from the kagome lattice. These discoveries make CsV3Sb5 as an ideal platform to study the interplay among nontrivial band topology, CDW and unconventional superconductivity.

${\mathrm{MnBi}}_{2}{\mathrm{Te}}_{4}$ has attracted tremendous interest as the first discovered intrinsic magnetic topological insulator. Due to its heavily $n$-doped nature, hole doping is required to isolate the effects of the topological states from the bulk, which is necessary for further electronic applications. Here, we systematically measure the resistivity, Seebeck coefficient, and thermal conductivity of $\mathrm{Mn}{({\mathrm{Bi}}_{1\ensuremath{-}x}{\mathrm{Sb}}_{x})}_{2}{\mathrm{Te}}_{4}\phantom{\rule{0.16em}{0ex}}(0\phantom{\rule{0.16em}{0ex}}\ensuremath{\le}x\ensuremath{\le}0.51)$ single crystals. We find that the carrier concentrations at room temperature can be continuously tuned from $\ensuremath{-}9.47\ifmmode\times\else\texttimes\fi{}{10}^{19}$ to $5.21\ifmmode\times\else\texttimes\fi{}{10}^{19}\phantom{\rule{4pt}{0ex}}{\mathrm{cm}}^{\ensuremath{-}3}$ while varying $x$ from 0 to 0.51. In the crystals with the Fermi level located close to the charge neutral point in the bulk band gap, drastic changes in the resistivity, Seebeck coefficient, and thermal conductivity are observed around a certain temperature ${T}^{*}$. Our results suggest that the bipolar effect possibly plays an important role in determining the transport properties in narrow bulk band topological insulators when the Fermi level is located near the charge neutral point inside the bulk gap.

Understanding the competition between superconductivity and other ordered states (such as antiferromagnetic or charge-density-wave (CDW) state) is a central issue in condensed matter physics. The recently discovered layered kagome metal AV3Sb5 (A = K, Rb, and Cs) provides us a new playground to study the interplay of superconductivity and CDW state by involving nontrivial topology of band structures. Here, we conduct high-pressure electrical transport and magnetic susceptibility measurements to study CsV3Sb5 with the highest Tc of 2.7 K in AV3Sb5 family. While the CDW transition is monotonically suppressed by pressure, superconductivity is enhanced with increasing pressure up to P1 ≈ 0.7 GPa, then an unexpected suppression on superconductivity happens until pressure around 1.1 GPa, after that, Tc is enhanced with increasing pressure again. The CDW is completely suppressed at a critical pressure P2 ≈ 2 GPa together with a maximum Tc of about 8 K. In contrast to a common dome-like behavior, the pressure-dependent Tc shows an unexpected double-peak behavior. The unusual suppression of Tc at P1 is concomitant with the rapidly damping of quantum oscillations, sudden enhancement of the residual resistivity and rapid decrease of magnetoresistance. Our discoveries indicate an unusual competition between superconductivity and CDW state in pressurized kagome lattice., The recently discovered kagome metal AV3Sb5 is a new playground to study the interplay between superconductivity and charge-density-wave (CDW) state. Here, the authors report pressure-dependent evolution of CDW and superconductivity in CsV3Sb5, suggesting an unusual competition between the two phases.

Aiming at the different threat levels under phased array radar multi-target tracking, the Bayesian Cramer-Rao Lower Bound (BCRLB) of the target position estimation is used as the allocation criterion, this paper establishes a multi-target tracking time resource allocation optimization model based on threat degree. The model based on threat degree to track the target can be divided into two categories, different types with different time resource allocation method. Due to the time-consuming operation of this model and optimization algorithm, this paper also proposes a multi-target tracking time resource fitting method based on BP neural network. Computer simulation shows that the model and method can keep the target tracking in the best state, and the BP neural network will reduce the time consumption by thousands of times.

In this work, two organic-ion-intercalated $\mathrm{Sn}{\mathrm{Se}}_{2}$ superconductors, ${(\mathrm{TBA})}_{x}\mathrm{Sn}{\mathrm{Se}}_{2}$ $({T}_{c}\ensuremath{\sim}6.4\phantom{\rule{0.16em}{0ex}}\mathrm{K})$ and ${(\mathrm{CTA})}_{x}\mathrm{Sn}{\mathrm{Se}}_{2}$ $({T}_{c}\ensuremath{\sim}7.1\phantom{\rule{0.16em}{0ex}}\mathrm{K})$, are synthesized by an electrochemical intercalation method. Via the intercalation of organic ions, the interlayer distance is dramatically enlarged from 6.12 \AA{} of pristine $\mathrm{Sn}{\mathrm{Se}}_{2}$ to 18.62 and 14.74 \AA{} for ${(\mathrm{TBA})}_{x}\mathrm{Sn}{\mathrm{Se}}_{2}$ and ${(\mathrm{CTA})}_{x}\mathrm{Sn}{\mathrm{Se}}_{2}$, respectively. Bulk magnetic susceptibility measurements suggest that both superconductors exhibit a strong anisotropic superconducting shielding effect below ${T}_{c}$. Further measurements of resistivity, I-V characteristic curves, and magnetoresistance reveal a quasi-two-dimensional (2D) superconductivity in ${(\mathrm{CTA})}_{x}\mathrm{Sn}{\mathrm{Se}}_{2}$. The present work suggests that the organic-ion-intercalation method can induce quasi-2D superconductivity in $\mathrm{Sn}{\mathrm{Se}}_{2}$ layers and provides a simple and practical strategy to explore 2D superconductivity as well as other 2D phenomena in layered materials.

We present a study of the Nernst effect in an iron-based superconductor with a nontrivial band topology ${\mathrm{Fe}}_{1+y}{\mathrm{Te}}_{1\ensuremath{-}x}{\mathrm{Se}}_{x}$. A nonzero Nernst signal is observed in a narrow temperature region around the superconducting transition temperature ${T}_{c}$ at a zero field. This anomalous Nernst signal shows symmetric dependence on the external magnetic field and indicates an unconventional vortex contribution in an $s$-wave superconductor with a strong spin-orbit coupling, which is originated from the local magnetic moments of the interstitial Fe atoms. Our experiments also provide the first evidence of a locally broken time-reversal symmetry in bulk ${\mathrm{Fe}}_{1+y}{\mathrm{Te}}_{1\ensuremath{-}x}{\mathrm{Se}}_{x}$ single crystals.

本文报道了1例喉IgG4相关性疾病的患者。患者因"声音嘶哑"发现"喉肿物"，多次病理活检均提示为良性病变，然这与患者喉部影像提示"喉肿物侵犯突破甲状软骨板"的恶性征象明显不符。经手术完整切除喉肿物后病理最终诊断"喉IgG4相关性疾病"。明确诊断后于风湿免疫科行激素和环磷酰胺规律治疗，治疗随访未见喉IgG4相关性疾病复发，患者声嘶较术前改善，对治疗效果满意，随访8个月无不适。.

The point-contact-spectroscopy measurement is a powerful method to detect the superconducting gap and the spin polarization of materials. However, it is difficult to get a stable and clean point contact by conventional techniques. In this work, we fabricate multiple point contacts by depositing Au nanoparticle arrays on the surface of a superconductor through an anodic aluminum oxide patterned shadow mask. We obtained the superconducting gaps of niobium nitride thin film (NbN, = 16 K) and iron superconductors CaFe0.88Co0.12AsF single crystals (Ca-1111, T-c= 21.3 K) by fitting the point-contact spectroscopy with the Blonder-Tinkham-Klapwijk theory. We found that NbN's gap (Delta) exhibits the BCS-like temperature dependence with Delta approximate to 2.88 meV at 0 K and 2 Delta/k(B)T(C) approximate to 4.22 in agreement with previous reports. By contrast, Ca-1111 has a multigap structure with Delta(l) approximate to 1.99 meV and Delta(2) approximate to 5.01 meV at 0 K, and the ratio between the superconducting gap and Tc is 2 Delta(1)/KBTc = 2.2 and 2 Delta(2)/KBTc = 5.5, suggesting an unconventional paring mechanism of Ca-1111 also in agreement with previous reports on other Fe-based superconductors. Our multiple point-contacts method thus provides an alternative way to perform measurements of the superconducting gap.

Transforming growth factor beta 1 (TGF-β1) can promote myocyte hypertrophy, thus playing an important role in ventricular remodeling after myocardial infarction (MI).In this study, the model of MI was established in rats through ligating the left anterior descending coronary artery. Subsequently, the messenger ribonucleic acid (mRNA) and protein expression levels of TGF-β1 in myocardial cells in both model group and sham operation group were determined. The effects of TGF-β1 treatment on myocardial cell apoptosis in MI rats were explored. Moreover, the changes of mitogen-activated protein kinase (MAPK) signaling pathway in rats with acute MI were verified. In addition, the protein expressions of phosphorylated-MAPK kinases 3/6 (p-MKK3/6) and MKK3/6 in myocardial cells of the two groups were analyzed.The mRNA and protein expression levels of TGF-β1 in myocardial cells of acute MI rats were significantly higher than those in the sham operation group (p0.01). After treatment with TGF-β1, the expression level of B-cell lymphoma 2 (Bcl-2) associated X protein (Bax) was obviously down-regulated. The Bax/Bcl-2 ratio was notably lower than that in control group (p0.01). Meanwhile, the proportion of apoptotic cells decreased remarkably (p0.01). In the model group, no evident change was observed in the protein expression level of MKK3/6, whereas the levels of p-MKK3/6 were prominently up-regulated (p0.01).TGF-β1 can activate MKK3/6 in the MAPK signaling pathway to resist the apoptosis of myocardial cells in acute MI rats.

To investigate whether Teriparatide (TP) contributed to the osteogenic differentiation of human marrow mesenchymal cells (hMSCs) through the regulation of miR-375, thereby alleviating osteoporosis (OP).The expression levels of miR-375 in the serum and hMSCs of patients with OP were determined by quantitative real time-polymerase chain reaction (qRT-PCR). hMSCs were extracted from bone marrows of OP patients and underwent osteogenic differentiation for 1 day, 3 days, 7 days and 10 days, respectively. The mRNA levels of alkaline phosphatase (ALP), osteocalcin (OCN) and runt-related transcription factor 2 (RUNX2) in TP-treated hMSCs transfected with miR-375 mimics or negative control were detected by qRT-PCR. Western blot was conducted to determine the protein expression of RUNX2 in TP-treated hMSCs transfected with miR-375 mimics or negative control. Besides, the osteogenic capacity and mineralization capacity of hMSCs were evaluated by the detection of ALP activity, ALP staining and Alizarin red staining, respectively. Dual-Luciferase reporter gene assay was performed to verify the binding between RUNX2 and miR-375. Subsequently, RUNX2 expression was detected in hMSCs transfected with miR-375 mimics or inhibitor. Rescue experiments were finally performed to determine whether miR-375 was involved in TP-induced osteogenic differentiation by targeting RUNX2.MiR-375 remained at a high level in serum of OP patients, while gradually decreased with the prolongation of osteogenic differentiation in isolated hMSCs. TP induction increased the osteogenic and mineralization capacities of hMSCs, which were inhibited after miR-375 overexpression. Through Dual-Luciferase reporter gene assay, we confirmed the binding relationship between miR-375 and RUNX2. Besides, both mRNA and protein levels of RUNX2 were negatively regulated by miR-375. Finally, we verified that co-overexpression of miR-375 and RUNX2 in TP-induced hMSCs significantly enhanced the mineralization capacity compared to overexpression of miR-375 alone.Teriparatide promoted the osteogenic differentiation of hMSCs through miR-375/RUNX2 axis.

Manipulating collectively ordered electronic and magnetic states in a correlated system is at the core of condensed matter physics. Besides tuning the carrier density of a crystal, the latest developed field-effect transistor (FET) with a solid ion conductor (SIC) can also drive ions into the crystal and lead to structural transformations that are difficult to access with conventional methods including conventional field-effect transistors. Here, we exploit the SIC-FET gating technique to realize a metastable phase in (Li,Fe)OHFeS thin flakes, and achieve a rich phase diagram involving superconductivity, soft ferromagnetism, and hard ferromagnetism. With the injection of Li ions into the thin flake, the superconductivity is gradually suppressed and a soft ferromagnetic phase with new crystal structure sets in, evidenced by the anomalous Hall effect and magnetoresistance measurements. Further injecting Li ion drives the soft ferromagnetic state into a hard ferromagnetic state, where different types of magnetic interactions dominate due to the simultaneous tuning of carrier density and magnetic Fe ion concentration in the Li ion injection process. Our paper paves a way to control structural phase transformations as well as physical properties by the electric field. These findings demonstrate the superior performance of the SIC-FET in regulating the physical properties of layered crystals and its potential applications for multifunctional devices.

The FeSe-based superconductors exhibit a wide range of critical temperature Tc under a variety of material and physical conditions, but extensive studies to date have yet to produce a consensus view on the underlying mechanism. Here we report on a systematic Raman scattering work on intercalated FeSe superconductors Lix(NH3)yFe2Se2 and (Li,Fe)OHFeSe compared to pristine FeSe. All three crystals show an anomalous power-law temperature dependence of phonon linewidths, deviating from the standard anharmonic behavior. This intriguing phenomenon is attributed to electron-phonon coupling effects enhanced by electron correlation, as evidenced by the evolution of the A1g Raman mode. Meanwhile, an analysis of the B1g mode, which probes the out-of-plane vibration of Fe, reveals a lack of influence by previously suggested structural parameters, and instead indicates a crucial role of the joint density of states in determining Tc. These findings identify carrier doping as the direct factor driving and modulating superconductivity in FeSe-based compounds., 6 pages, 4 figures

Nano B2 FeCu ordered clusters and multiphase microstructure consisting of intercritical ferrite, tempered martensite and nano-γ phase (reverted austenite) were obtained by two-step heat treatment involving intercritical annealing and intercritical tempering. The experimental steel with nano Cu precipitates and nano-γ phase exhibited high strength and high ductility combination. The yield strength and total elongation of the experimental steel increased from 758 MPa and 16.8% to 984 MPa and 29.5% after the second step intercritical tempering for 5 min. High resolution transmission electron microscopy (HRTEM) and three-dimensional atom probe (3DAP) studies provided evidence to support that high density of nano B2 FeCu ordered clusters contributed to high strength. First principle calculations suggested that the feasibility of B2 FeCu nano-ordered clusters, and the stability of B2 structure is related to the coherent stress field at the interface between clusters and the BCC-Fe matrix. The average size of B2 FeCu nano-ordered clusters was 4 nm with a lattice constant of 0.2893 nm and an orientation relationship of (1 1 0)B2//(1 1 0)α and [0 0 1]B2//[0 0 1]α. 9R Cu without twinned structure was discovered at different tempering times. The proportion of Cu in Cu precipitates varied from 24.4 at% to 61.2 at% with change in crystal structure and increase in the size of precipitates. The significant increase in yield strength is discussed in terms of ordered domain strengthening, modulus strengthening and lattice misfit strengthening mechanisms. Bright field TEM image and selected area electron diffraction (SAED) pattern discovered and proved that spindle nano-γ phase was present at phase boundary between tempered martensite and intercritical ferrite. The size of them were among 242–375 nm in length and 52–80 nm in width. The two needle tip ends of nano-γ phase were just at phase boundaries, indicating the preferred growth direction. (1 −1 1)γ plane of nano-γ phase was parallel to (1 −1 0)α plane of the adjacent tempered martensite. The effect of nano-γ phase on enhancing the plasticity was revealed by instantaneous work hardening index curve.

The observation of quantized anomalous Hall conductance in the forced ferromagnetic state of $\mathrm{MnB}{\mathrm{i}}_{2}\mathrm{T}{\mathrm{e}}_{4}$ thin flakes has attracted much attention. However, a strong magnetic field is needed to fully polarize the magnetic moments due to the large antiferromagnetic interlayer exchange coupling. Here, we reported the magnetic and electrical transport properties of the magnetic van der Waals $\mathrm{MnB}{\mathrm{i}}_{2}\mathrm{T}{\mathrm{e}}_{4}{(\mathrm{B}{\mathrm{i}}_{2}\mathrm{T}{\mathrm{e}}_{3})}_{n}$ ($n=1,2$) single crystals, in which the interlayer antiferromagnetic exchange coupling is greatly suppressed with the increase of the separation layers $\mathrm{B}{\mathrm{i}}_{2}\mathrm{T}{\mathrm{e}}_{3}$. $\mathrm{MnB}{\mathrm{i}}_{4}\mathrm{T}{\mathrm{e}}_{7}$ and $\mathrm{MnB}{\mathrm{i}}_{6}\mathrm{T}{\mathrm{e}}_{10}$ show weak antiferromagnetic transition at 12.3 and 10.5 K, respectively. The ferromagnetic hysteresis was observed at low temperature for both of the crystals, which is quite crucial for realizing the quantum anomalous Hall effect without external magnetic field. Our work indicates that $\mathrm{MnB}{\mathrm{i}}_{2}\mathrm{T}{\mathrm{e}}_{4}{(\mathrm{B}{\mathrm{i}}_{2}\mathrm{T}{\mathrm{e}}_{3})}_{n}$ ($n=1,2$) provides an ideal platform to investigate the rich topological phases with their two-dimensional limits.