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Ferromagnets are known to support spin-polarized currents that control various spin-dependent transport phenomena useful for spintronics. On the contrary, fully compensated antiferromagnets are expected to support only globally spin-neutral currents. Here, we demonstrate that these globally spin-neutral currents can represent the N\'eel spin currents, i.e. staggered spin currents flowing through different magnetic sublattices. The N\'eel spin currents emerge in antiferromagnets with strong intra-sublattice coupling (hopping) and drive the spin-dependent transport phenomena such as tunneling magnetoresistance (TMR) and spin-transfer torque (STT) in antiferromagnetic tunnel junctions (AFMTJs). Using RuO$_{2}$ and Fe$_{4}$GeTe$_{2}$ as representative antiferromagnets, we predict that the N\'eel spin currents with a strong staggered spin-polarization produce a sizable field-like STT capable of the deterministic switching of the N\'eel vector in the associated AFMTJs. Our work uncovers the previously unexplored potential of fully compensated antiferromagnets and paves a new route to realize the efficient writing and reading of information for antiferromagnetic spintronics.

The evolution of subgrains, dislocations and mechanical properties in a 2524Al alloy during high-strain rolling is investigated in this work. The results show that there are numerous coarse second phases of Al2Cu and Al2CuMg along the dendritic grain boundaries in the cast 2524Al alloy. The second phases are mostly dissolved into the matrix after homogenization. After hot rolling, solution treatment and aging, and cold rolling, the grains are elongated in the rolling direction, a large number of fine and disperse precipitates are present in the grains and along the grain boundaries, and the deformation process generates a mass of subgrains and a high density of dislocations. After cold rolling, the mechanical properties of the 2524 alloy sheet are improved, i.e., ultimate tensile strength of 684 MPa, yield strength of 581 MPa and elongation of 3%. The high strength may be due to the high dislocation density, the mass of fine and dispersed distribution precipitates and the many subgrains.

Tail-biting convolutional codes (TBCCs) have become a research hotspot in the short-block-length regime due to the growing interest in strong short packet com-munications with low latency and ultra-reliability. TBCCs can maintain the decoding performance without rate loss caused by the tailed bits in the traditional convolutional encoder, which also have good rate compatibility with bet¬ter decoding performance than those of the iterative scheme for short block length codes. In this paper, a search algorithm is proposed to construct a set of rate-compatible TBCCs (RC-TBCCs) with consistent good frame error rate (FER) performance for fixed information length at various code rates. The algorithm considers the minimum distance profile of TBCCs. A set of RC-TBCCs is constructed for code rates from 1/3 to 1/8. The simulation results show that the proposed RC-TBCCs are superior to the LTE standard RC-TBCCs at different code rates.

Cisplatin is a standard chemotherapeutic agent for advanced bladder cancer, but its efficacy is limited due to drug resistance. Vitamin D3 may reverse cancer multidrug resistance, but the potential molecular mechanisms are still only partially known. The purpose of this study was to explore the mechanism by which vitamin D3 reverses cisplatin resistance in bladder cancer to improve therapeutic efficacy and ameliorate the prognosis of cisplatin-resistant bladder cancer.The levels of vitamin D3 and sirtuin 1 protein were detected in cisplatin-resistant bladder cancer patients and cisplatin-sensitive patients. The cisplatin-resistant bladder cancer cell lines T24/DDP and UMUC3R were used as cell experimental models, and the migration, apoptosis, mitochondrial reactive oxygen species accumulation and autophagy of cells were assessed in the present study.Vitamin D3 levels were decreased, and sirtuin 1 protein levels were increased in cisplatin-resistant bladder cancer patients compared with cisplatin-sensitive bladder cancer patients. Vitamin D3 treatment markedly repressed sirtuin 1 expression, and overexpression of the sirtuin 1 gene led to mitochondrial reactive oxygen species generation, promoted the initiation of autophagosome formation and enhanced autophagic flux. Cisplatin treatment in the presence of vitamin D3 inhibited cell invasion and migration and induced apoptosis and enhancing the sirtuin 1 gene abolished the effect of vitamin D3 by regulating mitochondrial reactive oxygen species accumulation and autophagosome formation.These data support a mechanism wherein the sirtuin 1 gene plays a crucial role in vitamin D3 reversing cisplatin resistance in bladder cancer and may provide useful preventive and therapeutic applications in the future.

Chiral materials have attracted significant research interests as they exhibit intriguing physical properties, such as chiral optical response, spin-momentum locking, and chiral induced spin selectivity. Recently, layered transition metal dichalcogenide 1T-TaS_{2} has been found to host a chiral charge density wave (CDW) order. Nevertheless, the physical consequences of the chiral order, for example, in electronic structures and the optical properties, are yet to be explored. Here, we report the spectroscopic visualization of an emergent chiral electronic band structure in the CDW phase, characterized by windmill-shaped Fermi surfaces. We uncover a remarkable chirality-dependent circularly polarized Raman response due to the salient in-plane chiral symmetry of CDW, although the ordinary circular dichroism vanishes. Chiral Fermi surfaces and anomalous Raman responses coincide with the CDW transition, proving their lattice origin. Our Letter paves a path to manipulate the chiral electronic and optical properties in two-dimensional materials and explore applications in polarization optics and spintronics.

Anomalous Hall effect (AHE) is a fundamental spin-dependent transport property that is widely used in spintronics. It is generally expected that currents carrying net spin polarization are required to drive the AHE. Here we demonstrate that, in contrast to this common expectation, a spin-neutral tunneling AHE (TAHE), i.e. a TAHE driven by spin-neutral currents, can be realized in an antiferromagnetic (AFM) tunnel junction where an AFM electrode with a non-spin-degenerate Fermi surface and a normal metal electrode are separated by a non-magnetic barrier with strong spin-orbit coupling (SOC). The symmetry mismatch between the AFM electrode and the SOC barrier results in an asymmetric spin-dependent momentum filtering of the spin-neutral longitudinal current generating the transverse Hall current in each electrode. We predict a sizable spin-neutral TAHE in an AFM tunnel junction with a RuO$_{2}$-type AFM electrode and a SnTe-type SOC barrier and show that the Hall currents are reversible by the N\'eel vector switching. With the Hall angle being comparable to that in conventional AHE bulk materials, the predicted spin-neutral TAHE can be used for the N\'eel vector detection in antiferromagnetic spintronics.

Lead-free Na0.5Bi0.5TiO3 (NBT) exhibiting large polarization and a high Curie temperature can be considered as a promising candidate for dielectric capacitors. The large polarization switching hysteresis and low breakdown field, however, restrict the performance optimization. Herein, epitaxial NBT-based high-entropy Na0.5Bi0.5Ti0.7Hf0.1Zr0.1Sn0.1O3 (NBTHZS) films are designed and prepared by solution-based processing. Compared with the NBT film, the polarization switching hysteresis is depressed and the breakdown field is significantly improved for the NBTHZS film due to the high-entropy effects. Therefore, the NBTHZS film achieves a ∼16 times enhancement of energy density (from 5.1 J/cm3 of the NBT film to 81 J/cm3 of the NBTHZS film) and a high efficiency of 74.1% as well as an excellent performance reliability. The results shed light on enhancing dielectric energy storage properties of NBT-based films by forming high-entropy structures.

This study collected nasopharyngeal swab specimens from severe respiratory infection cases in First People's Hospital of Yuhang District during 2016-2019. Real-time PCR was used to detect respiratory syncytial virus (RSV). Rate of RSV positive detection were analysised in different age groups and different months. A total of 973 nasopharyngeal swab specimens of severe respiratory infection cases were collected, and the total positive rate of nucleic acid test of RSV was 6.47%; The detection rate of nucleic acid in male is higher than that in female, with no statistical differences (收集2016年1月至2019年12月杭州市余杭区第一人民医院的严重急性呼吸道感染病例鼻咽分泌物标本，采用荧光定量PCR方法进行RSV病毒核酸检测；检测后分析不同年龄组、不同月份RSV阳性检出情况。结果显示，共收集并检测973份鼻咽拭子标本中，63份标本RSV核酸检测阳性，阳性检出率为6.47%；核酸检出率男性大于女性，但两者差异无统计学意义（

Design and realization of high-efficiency p-type thermoelectric materials with excellent performance are the demand for integrated thermoelectric components. Compared with single crystal bulk materials, thermoelectric thin films are more suitable for the miniaturization of thermoelectric devices. Here, c-axis oriented CuRh1− xMg xO2 (x = 0, 0.05, and 0.1) thin films were prepared and the thermoelectric properties are reported. The power factor of a p-type 10% Mg-doped CuRhO2 thin film shows a large value of 535.7 μW K–2 m-1 at 300 K. The results suggest that the hole-doped CuRhO2 thin films can be regarded as potential p-type thermoelectric oxide and will pave an avenue to develop Rh-based thermoelectric thin films.

CaBi2Nb2O9 ceramics were fabricated via the solid-state reaction method by the addition of B2O3 as a sintering aid at lower sintering temperatures than that prepared without B2O3. Ferroelectricity, piezoelectricity, and resistivity can be still greatly enhanced when the sintering temperature is decreased from 1075 °C for CaBi2Nb2O9 to 975 °C for CaBi2Nb2O9–0.25 wt. % B2O3. The high resistivity and weak c-axis texture ensure that the ceramics can be fully polarized in a high enough electric field. The increased spontaneous ferroelectric and remanent polarization result in a significant enhancement in the piezoelectric properties of CaBi2Nb2O9–0.25 wt. % B2O3. The sample sintered at 975 °C possesses a high piezoelectric coefficient d33 of ∼15.0 pC/N and resistivity of 1.4 × 106 Ω cm (at 600 °C) along with a high ferroelectric Curie temperature TC of ∼954 °C. This work is beneficial for the preparation of high-temperature piezoelectric ceramics with excellent electrical properties at a low sintering temperature.

The traditional strategy for transparent conducting oxides (TCOs) follows the path of chemical design by increasing carrier concentrations in insulators through deliberate doping to coordinate the exclusive properties of electrical conductivity with optical transparency. Despite the success of n-type TCOs, the developed p-type TCOs based on chemical design exhibit much lower performance than the n-type counterparts primarily constrained by the hole doping trouble. Recently, the correlated metal of a V2O3 thin film has been reported as high-performance p-type TCOs with high hole concentration (>1022 cm−3). In this paper, we propose an alternative approach of compressive strain in V2O3 thin films toward further increasing the carrier concentration and, consequently, enhancing the performance of p-type TCOs. The compressive strain of the V2O3 thin film is realized by the lattice mismatch between V2O3 and Al2O3. Interestingly, carrier concentrations in strained V2O3 thin films can be increased by several times exceeding 1023 cm−3, which directly correlates with the increase (decrease) in [Formula: see text] ([Formula: see text]) orbital occupation as verified by the Raman spectrum. Meanwhile, the screened plasma energy of a strained V2O3 thin film shifts to ∼1.6 eV, which is less than 1.75 eV to assure the opening of the transparency window in the visible region. As a result, strained V2O3 thin films exhibit enhanced performance as p-type TCOs with relatively high figure of merit. These results indicate that the structural modification can open up an effective approach for increasing the carrier concentration and enhancing the performance of p-type TCOs.

We report a cluster spin glass behavior, multiferroicity and magnetoelectric (ME) effects in the single crystals of 0.46[Formula: see text]-0.54[Formula: see text]. The crystals are found to possess a pseudo-cubic structure with a weak tetragonal distortion and show ferroelectricity at room temperature with a ferroelectric curie temperature of [Formula: see text] K. The cluster spin glass state in the crystal is evidenced by detailed dc and ac magnetic experiments, including thermo-remnant magnetization, aging effect, memory effect, etc. Magnetodielectric effects, poling enhanced magnetism, and electric field induced acceleration of magnetization relaxation in the spin glass state are observed and ascribed mainly to spin-lattice coupling. These results might suggest an effective route to improve ferromagnetism and ME effects by constructing a spin glass state in [Formula: see text]-based antiferromagnetic multiferroics.

Topological semimetals (TSMs) present intriguing quantum states and have attracted much attention in recent years because of exhibiting various anomalous magneto-transport phenomena. Theoretical prediction shows that some novel phenomena, such as negative magnetoresistance (MR) and the planar Hall effect (PHE), originate from the chiral anomaly in TSMs. In this work, high-field (33 T) Shubnikov-de Haas (SdH) oscillations are obtained to reveal the topology of PtSn

The novel coronavirus 2019 (COVID-19) infected patients by binding human ACE2, leading to severe pneumonia and highly mortality rate in patients. At present, there is no definite and effective treatment for COVID-19. ACE2 plays an important role in the RAS, and the imbalance between ACE/Ang II/AT1R pathway and ACE2/Ang (1-7)/Mas receptor pathway in the RAS system will lead to multi-system inflammation. Increased ACE and Ang II are poor prognostic factors for severe pneumonia. Animal studies have shown that RAS inhibitors could effectively relieve symptoms of acute severe pneumonia and respiratory failure. The binding of COVID-19 and ACE2 resulted in the exhaustion of ACE2, and then ACE2/Ang (1-7)/Mas receptor pathway was inhibited. The balance of the RAS system was broken, and this would lead to the exacerbation of acute severe pneumonia. Therefore, we speculate that ACEI and AT1R inhibitors could be used in patients with COVID-19 pneumonia under the condition of controlling blood pressure, and might reduce the pulmonary inflammatory response and mortality.新型冠状病毒通过与人体血管紧张素转化酶2（ACE2）结合感染产生重症肺炎，传染性强，病死率高，目前无确切有效的治疗方式。ACE2是肾素-血管紧张素系统（RAS）的重要组成部分，RAS系统中ACE/Ang II/AT1R通路与ACE2/Ang (1-7)/Mas受体通路失衡将导致多系统炎症。ACE和Ang II升高是重症肺炎的不良预后因素。动物实验结果显示，应用RAS抑制剂可以有效缓解急性重症肺炎症状，缓解呼吸衰竭。新型冠状病毒与ACE2的结合导致ACE2耗竭，ACE2/Ang (1-7)/Mas受体通路受到抑制，RAS系统失衡，使新型冠状病毒肺炎患者病死率升高。因此，在控制血压的情况下，对新型冠状病毒肺炎患者应用ACEI及AT1R抑制剂，有可能减轻患者肺部炎症反应，降低患者病死率。.

The structural, magnetic, electronic, and thermal transport properties of Sr3Fe2O6.6 single crystal were investigated by the room-temperature X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electrical resistivity ρ ( T ) , specific heat C p ( T ) , and electron spin resonance (ESR) measurement. The single crystal has been grown by the floating zone method. The as-grown crystal can be indexed by a tetragonal lattice with the space group I 4 / m m m . The oxygen content determined by the XPS measurement is approximately 6.6, which was verified in the magnetic susceptibility measurement. The incommensurate antiferromagnetic-transition temperature is about T N = 62 K , and the magnetic susceptibility of the sample were anisotropic. The electrical resistivity ρ ( T ) shows a semiconducting behavior with an energy gap E α = 0.134 eV and non-magnetoresistance behavior. The C p ( T ) data exhibits that the Debye temperature Θ D is larger than the theoretical value. The reciprocal of magnetic susceptibility to CW law is verified by the ESR results. The resonance field and the g-factor exhibit anisotropy.

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.

The electronic and magnetic properties of ZrS2 nanoribbons (NRs) are investigated based on first principles calculations. It is found that the ZrS2 NRs with armchair edges are all indirect band gap semiconductors without magnetism, and the band gap exhibits odd–even oscillation behavior with the increase of the ribbon width. For the NRs with zigzag edges, those with both edges S-terminated are nonmagnetic direct band gap semiconductors, and the gap decreases monotonically as a function of the ribbon width. However, the NRs with one edge S-terminated and the other edge Zr-terminated are ferromagnetic half-metals, while those with both edges Zr-terminated tend to be ferromagnetic half-metals when the width N ≥ 9. The magnetism of both systems mainly originates from the unsaturated edge Zr atoms. Depending on the different edge configurations and ribbon widths, the ZrS2 NRs exhibit versatile electronic and magnetic properties, making them promising candidates for applications in electronics and spintronics.

Layered $\mathrm{V}{\mathrm{I}}_{3}$ has emerged as a new two-dimensional (2D) van der Waals bonded ferromagnetic semiconductor, which is an important class of materials for spintronics applications. However, the origin of ferromagnetism in $\mathrm{V}{\mathrm{I}}_{3}$ is still missing. In this work, we systematically investigate the anisotropy of magnetic properties and entropy change in a $\mathrm{V}{\mathrm{I}}_{3}$ single crystal. Based on the measurement of the angular-dependent magnetization, there is a weak sixfold in-plane symmetry and fourfold out-of-plane symmetry, indicating $\mathrm{V}{\mathrm{I}}_{3}$ possesses weak in-plane anisotropy and large out-of-plane anisotropy. Meanwhile, anisotropy of magnetic entropy change $\mathrm{\ensuremath{\Delta}}{S}_{M}(T,H)$ is further studied by the isothermal magnetization, showing that the difference of $\ensuremath{-}\mathrm{\ensuremath{\Delta}}{S}_{M}^{\mathrm{max}}$ between the $c$ axis and $ab$ plane reaches a maximum value $\ensuremath{\sim}0.95\phantom{\rule{0.16em}{0ex}}\mathrm{J}\phantom{\rule{0.16em}{0ex}}\mathrm{k}{\mathrm{g}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}{\mathrm{K}}^{\ensuremath{-}1}$ with a magnetic field change of 4.5 T. With the scaling analysis of $\mathrm{\ensuremath{\Delta}}{S}_{M}$, the critical exponents can be obtained and indicate a crossover between 2D-Ising and tricritical mean-field magnetic interactions, and the rescaled $\mathrm{\ensuremath{\Delta}}{S}_{M}(T,H)$ curves fall onto a universal curve, demonstrating a second-order type of magnetic transition.

不孕症是1种低生育力状态，严重危害育龄期女性的生殖健康，指1对配偶未采取避孕措施，有规律性生活至少12个月未能获得临床妊娠。广义的不孕症包括不能妊娠和不能获得活产两个方面，本指南仅包括不能妊娠的相关内容。本指南是由中华医学会妇产科学分会妇科内分泌学组参考WHO、美国生殖医学学会（ASRM）、英国国家卫生和临床医疗优选研究所（NICE）的相关指南，并结合我国临床实践现状，经全国各级医疗机构专家函审最终制定，适用于全国各级各类医疗机构妇产科及男科执业医师对不孕症的诊断。.

The ${\mathrm{CoBr}}_{2}$ monolayer is predicted to be an intrinsically ferromagnetic (FM) semiconductor based on the first-principles calculations. The results of the magnetic anisotropy energy show that the ${\mathrm{CoBr}}_{2}$ monolayer has an easy magnetization plane and belongs to the family of two-dimensional $XY$ magnets. The exchange interactions and thus the magnetic properties can be effectively tuned by external strain and carrier doping. The biaxial tensile strain can induce FM-antiferromagnetic (AFM) phase transition in the ${\mathrm{CoBr}}_{2}$ monolayer, by which the Co-Br-Co bond angle is enlarged deviating far away from ${90}^{\ensuremath{\circ}}$. While the compressive strain stabilizes the FM state by reducing the nearest Co-Co distance and enhancing the $p\text{\ensuremath{-}}d$ hybridization between Co and Br atoms. The ${\mathrm{CoBr}}_{2}$ monolayer remains semiconducting for the whole range of strain investigated. For the carrier doping, however, the ${\mathrm{CoBr}}_{2}$ monolayer tends to be a half-metal for both hole and electron doping. Doping not only introduces itinerant carriers, but also enhances the $p\text{\ensuremath{-}}d$ hybridization between the Co and Br atoms, both of which enhance the FM coupling significantly. The tunability of the electronic and magnetic properties of ${\mathrm{CoBr}}_{2}$ monolayer makes it a promising candidate for future nanospintronic applications.

To investigate the influences of metformin on the proliferation and migration of endometrial cancer (EC) Ishikawa cells and its mechanism.After the EC Ishikawa cells were treated with metformin at a concentration of 10 mM for 24 h, the proliferation of cancer cells was detected via XTT [2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-car-boxanilide] assay and colony formation assay, and the migration and invasion of cancer cells were detected via wound healing assay and transwell assay. In addition, the expressions of epithelial-mesenchymal transition (EMT)-related proteins, E-cadherin and Vimentin, were detected via Western blotting, and immunofluorescence staining was performed for E-cadherin in cancer cells. Finally, the protein expression level of phosphatidylinositol 3-hydroxy kinase/protein kinase B/murine double minute 2 (PI3K/AKT/MDM2) signaling pathway in cancer cells was detected via Western blotting.Metformin inhibited the proliferation of Ishikawa cells in a concentration-dependent manner (0-10 mM) (p0.05). Moreover, metformin (10 mM) also inhibited the proliferation of Ishikawa cells in a time-dependent manner (0-72 h) (p0.05). The results of colony formation assay revealed that metformin (10 mM) could significantly inhibit the colony formation of Ishikawa cells (p0.05). The results of wound healing assay and transwell assay showed that metformin (10 mM) significantly inhibited the migration and invasion of Ishikawa cells (p0.05). According to further studies, metformin (10 mM) inhibited the EMT process in Ishikawa cells. Western blotting results manifested that the activation of PI3K/AKT/MDM2 signaling pathway was inhibited by metformin (p0.05).Metformin can inhibit the proliferation and migration of EC cells by inhibiting the activation of PI3K/AKT/MDM2 signaling pathway. Therefore, metformin is expected to be a new drug for the clinical treatment of EC.

The origin of the structural phase transition of $\mathrm{TaT}{\mathrm{e}}_{2}$ has been investigated through the measurements of the temperature-dependent Raman spectroscopy and first-principles calculations. Based on the experimental and the calculation results, some interpretations are present. Firstly, abnormal redshifts of few Raman peaks are observed around the structural distortion temperature ${T}_{S}\ensuremath{\sim}170\phantom{\rule{0.16em}{0ex}}\mathrm{K}$, which is thought to originate from the clustering of Ta atoms below ${T}_{S}$. Secondly, new modes of Raman spectrum below ${T}_{S}$ are present, which is suggested to be related to the possible transition of charge density wave (CDW) in $\mathrm{TaT}{\mathrm{e}}_{2}$ from the room temperature to the low temperature. The ground state of the $\mathrm{TaT}{\mathrm{e}}_{2}$ is the special charge modulation, which is related to the formation of Ta-Ta dimer structure at low temperature. All explanations have been supported by first-principles calculations. Our results suggest that $\mathrm{TaT}{\mathrm{e}}_{2}$ is an alternative platform to explore the charge-lattice coupling with rich structural and charge configurations in $M{X}_{2}$ systems, where $M$ is the transition metal ion (Nb, Ta, Mo, etc.) and $X$ is the chalcogenide one (S, Se, or Te).