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Grain boundary diffusion (GBD) is an effective process to enhance coercivity for Nd–Fe–B magnets with relatively low consumption of expensive heavy rare earths (HREs). For conventional GBD, the surface of the magnet is evenly covered by diffusion source, followed by diffusion heat treatment. In this work, a macroscopically heterogeneous GBD (MHGBD) process is proposed in order to further reduce the use of HRE resource. Based on the micromagnetic simulations, magnetically strengthening the edge area of the magnet is more effective than strengthening the center area in terms of coercivity enhancement for whole magnet. Hence, the HRE-based diffusion source was used for enhancing the edge area and the light rare-earth-based source was used for the center area. In details, Tb70Al20Cu10 and Pr70Al20Cu10 diffusion sources were covered at the edge and center areas of the two c-planes of a sintered Nd–Fe–B magnet, respectively. After the MHGBD by using Tb70Al20Cu10/Pr70Al20Cu10 (1:1, at.%), the magnet exhibits the increased coercivity from 1182 to 1911 kA/m. For comparison, the homogeneous diffusion of HRE-based Tb70Al20Cu10 source only enhances the coercivity to 1798 kA/m. The microstructure characterizations indicated that diffusion source of Tb70Al20Cu10 can form Tb-rich shells with high anisotropy field on the surface of Nd2Fe14B grains, and Pr70Al20Cu10 can provide more liquid grain boundary phase for GBD. The synergistic effect between these two sources improves the infiltration of Tb at the edge area of the magnet. Compared with the homogeneous Tb70Al20Cu10 diffusion, MHGBD process can not only exhibit higher diffusion efficiency, but also enhance the performance/cost ratio of the diffused magnets, evident by the increased coercivity enhancement per unit source from 0.23 to 0.51 kA m−1/($/kg). [ABSTRACT FROM AUTHOR]

Grain boundary diffusion (GBD) is an effective approach for improving the coercivity of Nd-Fe-B magnets with less heavy rare earth consumption. However, it generally only works well for thin magnets since the infiltration depth of diffusion source is limited. Here, a GBD approach that mainly diffuses the source from the edge and corner areas of the magnet, named selected area GBD (SAGBD), is proposed for treating thick magnets. After diffusing Pr-Tb-Al-Cu alloy by SAGBD, the coercivity of a 12-mm thick magnet was increased from 1070 to 1675 kA/m. By this approach, the coercivity enhancement with 1 wt. % Tb was 465 kA·m−1, 1.6 times as much as that by diffusion from two easy magnetization planes. For achieving a coercivity enhancement of ∼600 kA/m, the thickness of treated magnet was increased by 4 mm. Although the diffusion from six planes can further increase the coercivity, SAGBD leads to high efficient use of Tb and less reduction of remanence. The microstructure characterizations and micromagnetic simulation demonstrated that the edges and corners are magnetic "weak" areas of the magnet, and SAGBD can effectively hinder the nucleation of reversed domains in these places and the rapid reversal propagation in whole magnet. The present approach is important for the high-efficient use of the diffusion source and the fabrication of large-size Nd-Fe-B products with high stability. [ABSTRACT FROM AUTHOR]

• Anisotropic diffusion of heavy rare earth can be avoided for sintered Nd-Fe-B magnets. • The alloying of diffusion source distinctly enhance diffusion efficiency of Tb along a -axis. • The alloying of diffusion source inhibits the excessive lattice diffusion of Tb. Grain boundary diffusion (GBD) efficiency of heavy rare earths (HREs) for sintered Nd-Fe-B magnets along the easy magnetization direction (c -axis) was reported to be higher than that along the difficult one (a -axis). However, this conclusion is challenged by the present results, which indicate that the anisotropic diffusion does not exist, at least for some low-melting HRE-based diffusion sources. The alloying of Tb by Pr, Al and Cu can distinctly enhance the diffusion efficiency of Tb along the a -axis, resulting in quite similar coercivity enhancement to that diffused along the c -axis. The diffusion kinetic analysis and microstructure characterizations demonstrate that the alloying lowers the melting point of diffusion source and wets the intergranular phase as effective diffusion paths for Tb. This suppresses the excessive lattice diffusion of Tb and the formation of over-thick Tb-rich shells, which is beneficial to enhancing the Tb diffusion efficiency along the a -axis and reducing the total Tb consumption. [ABSTRACT FROM AUTHOR]

As a non-competitive N -methyl d -aspartate receptor antagonist, ketamine exerts rapid-onset and long-lasting antidepressant effects on depression, but some side effects limit its use. To identify a safer compound that may provide similar antidepressant effects, here we investigated whether CP-101,606, a selective NR2B receptor inhibitor, provides similar antidepressant effects and explored its underlying mechanisms. To mimic depressive-like behavior, mice were subjected to chronic unpredictable mild stress (CUMS) for 21 days. Mice were treated with CP-101,606 at 10, 20, and 40 mg/kg doses for 7, 14, and 21 days, respectively, followed by a sucrose preference test (SPT), tail suspension test (TST), and forced swimming test (FST). Western blot analysis was performed on several targets (mTOR, p-mTOR, p70S6K, p-p70S6K, PSD-95, and GluA1), along with immunohistochemistry (GluA1) and immunofluorescence (p-mTOR) assays, using hippocampal tissue. CP-101,606 at 20 and 40 mg/kg doses for 7 and 14 days and fluoxetine 10 mg/kg and CP-101606 20 mg/kg for 21 days ameliorated depression-like behaviors in the SPT, TST, and FST. The effects of CP-101,606 were associated with a reversal of the CUMS-induced decrease in mTOR (Ser2448) and p70S6K (Thr389) phosphorylation and increasing PSD95 and GluA1 synthesis in the hippocampus. Our results demonstrate that CP-101,606 produces antidepressant effects in CUMS mice, which may be mediated by mTOR signaling cascade upregulation. Our findings suggest the possible utility of CP-101,606 as a treatment for depression. • CP-101,606 reversed depression-like behaviors induced by CUMS. • CUMS-induced behavioral changes were correlated with synaptic proteins expression. • The molecular mechanisms of CP-101,606 may be related to mTOR signaling pathways. • Appropriate dose of CP-101,606 can exert its antidepressant effects. [ABSTRACT FROM AUTHOR]

Grain boundary diffusion (GBD) of multiple rare earths has proven effective in enhancing the performance of permanent magnets, whereas the diffusion behaviors are still unclear due to their intricate interactions. In this work, the synergistic effects of three rare earths (Tb, Ce, and La) on the grain boundaries diffusion process are investigated, achieving a high‐performance diffused Nd–Fe–B magnet with the high coercivity of 1822 kA m−1 and thermal stability of −0.447% K−1. This promotion originates from the improved diffusion depth of Tb at specific regions, induced by the coordination effects of Ce and La, as evidenced via electron probe microanalysis and the first‐principles calculations. It thus results in the uniform formation of Tb‐diffused magnetic harden grains, associated with the strongly pinned domain walls, which is further observed directly by in situ Lorentz transmission electron microscopy and reconstructed by micromagnetic simulations. The study provides insight into the role of element GBD mechanism and has promising potential to explore other element systems as diffusion sources for permanent magnets. [ABSTRACT FROM AUTHOR]

Grain boundary diffusion (GBD) of multiple rare earths has proven effective in enhancing the performance of permanent magnets, whereas the diffusion behaviors are still unclear due to their intricate interactions. In this work, the synergistic effects of three rare earths (Tb, Ce, and La) on the grain boundaries diffusion process are investigated, achieving a high‐performance diffused Nd–Fe–B magnet with the high coercivity of 1822 kA m−1 and thermal stability of −0.447% K−1. This promotion originates from the improved diffusion depth of Tb at specific regions, induced by the coordination effects of Ce and La, as evidenced via electron probe microanalysis and the first‐principles calculations. It thus results in the uniform formation of Tb‐diffused magnetic harden grains, associated with the strongly pinned domain walls, which is further observed directly by in situ Lorentz transmission electron microscopy and reconstructed by micromagnetic simulations. The study provides insight into the role of element GBD mechanism and has promising potential to explore other element systems as diffusion sources for permanent magnets. [ABSTRACT FROM AUTHOR]

Background: Impaired endometrial receptivity is a major reason for embryo implantation failure. There's a paucity of information regarding the role of circRNAs on endometrial receptivity. Here, we investigated the function of hsa_circ_001946 on endometrial receptivity and its mechanisms. Methods: A total of 50 women composing 25 with recurrent implantation failure and 25 who conceived after their implantation were recruited in this study. Expression of hsa_circ_001946, miR-135b, and HOXA10 was evaluated by quantitative RT-PCR (qRT-PCR) in biopsied endometrial tissue samples. The levels of HOXA10, and cell cycle markers (CCNB1, CDK1, and CCND1) were determined by IHC and western blotting assays. Binding relationship among miR-135b, hsa_circ_001946 and HOXA10 were confirmed by dual luciferase reporter assays and western blotting. MTT assays and cell cycle assays by FACS were employed to evaluate the proliferation and cell cycle of cells. T-HESCs were cultured with 1 µM medroxyprogesterone acetate (MPA) and 0.5 mM 8-bromoadenosine 3':5'-cyclic monophosphate (8-Br-cAMP) to induce decidualization. The mechanisms and functions of hsa_circ_001946 on decidualization were further assessed by qRT-PCR evaluating the expression of hsa_circ_001946, miR-135b, HOXA10 and decidual markers (PRL and IGFBP1) in T-HESCs. Results: Endometrial tissues from patients with recurrent implantation failure had lower hsa_circ_001946 expression, higher miR-135b expression, and lower HOXA10 expression. Hsa_circ_001946 promoted HOXA10 expression by sponging miR-135b in T-HESCs. Overexpression of hsa_circ_001946 restored cell proliferation and cell cycle that were disrupted by miR-135b overexpression in T-HESCs. Decidualized T-HESCs had higher hsa_circ_001946 expression, lower miR-135b expression, and higher HOXA10 expression. Overexpression of hsa_circ_001946 reversed the expression of decidual markers (PRL and IGFBP1) that were suppressed by miR-135b overexpression in T-HESCs. Conclusions: In conclusion, our findings suggest that hsa_circ_001946 promotes cell proliferation and cell cycle process and increases expression of decidualization markers to enhance endometrial receptivity progression via sponging miR-135b and elevating HOXA10. [ABSTRACT FROM AUTHOR]

Grain boundary diffusion (GBD) is an effective process to enhance the thermal stability and coercivity of sintered Nd-Fe-B magnets, but the low diffusion efficiency and high consumption of heavy rare earth (HRE) elements prevent further performance improvement and cost reduction of the magnets. Here, a Ni-containing dual-alloy Pr-Ni-Al/Dy-Ni-Al diffusion source is used to enhance both the diffusion efficiency of the Dy element and the anti-corrosion properties of Nd-Fe-B magnets. Pr-Ni-Al and Dy-Ni-Al alloys with different melting points exhibit different diffusion behaviors. The diffused low-melting Pr-Ni-Al alloy can construct continuous grain boundary, acting as an effective diffusion channel for the GBD of Dy-Ni-Al. As a result, the coercivity was enhanced from 1057 to 1662 kA/m by dual-alloy diffusion. For comparison, the coercivity increased only to 1548 kA/m by the diffusion of Pr-Dy-Ni-Al single-alloy with the same element contents. It was confirmed by composition and microstructure characterizations that Pr-Ni-Al/Dy-Ni-Al diffusion leads to a deeper diffusion of Dy. The constitution of continuous grain boundary phase and core-shell structure attributed to the enhancement of coercivity. Different from many HRE-based diffusion sources, the present Ni-containing sources can also greatly enhance the anti-corrosion properties of Nd-Fe-B magnets after GBD. The dual-alloy diffusion with low consumption and high diffusion efficiency of HREs, thus, shows good prospect for practical applications. • A Pr-Ni-Al/Dy-Ni-Al dual-alloy is proposed as grain boundary diffusion source. • Low-melting Pr-Ni-Al alloy provides diffusion channels for deep diffusion of Dy. • Deep diffusion and core-shell structure lead to enhanced coercivity. • Increased electric potential of GB phase results in improved corrosion resistance. [ABSTRACT FROM AUTHOR]

Grain boundary diffusion of heavy rare earth-based alloys can effectively enhance the coercivity of Nd-Fe-B magnets. Although the light rare earth elements can further improve the diffusion efficiency of Dy and Tb, they generally lead to reduced anti-corrosion properties of the magnets. Here, we successfully enhanced the coercivity and corrosion resistance of Nd-Fe-B magnets by GBD of Ni alloyed Pr-Tb-Cu diffusion source. The ternary Pr 35 Tb 35 Cu 30 alloy diffusion increased the coercivity of Nd-Fe-B magnet from 1330 to 1923 kA/m, but the coercivity was enhanced to 1990 kA/m by Pr 35 Tb 35 Ni 15 Cu 15 alloy diffusion. The formation of high-anisotropy (Nd,Tb) 2 Fe 14 B phase is the main reason for the coercivity improvement. Partially substitution of Cu by Ni can reduce the melting point of Pr 35 Tb 35 Cu 30 alloy, which is effective in promoting the infiltration of Tb. Cu is also a necessary element for improving the diffusion process, and the diffusion of Pr 35 Tb 35 Ni 30 alloy only increased the coercivity to 1747 kA/m. More interestingly, the diffusion of Pr 35 Tb 35 Ni 15 Cu 15 also enhanced the chemical stability of the magnet in NaCl solution. Scanning Kelvin probe force microscopy characterized that the modified GB phase in Pr 35 Tb 35 Ni 15 Cu 15 treated magnet exhibits a higher Volta potential than the 2:14:1 main phase, which is the main reason for the improved corrosion resistance. The present results suggest that the non-rare earth elements in the alloy diffusion sources play important roles in enhancing both coercivity and corrosion resistance of Nd-Fe-B magnets. • Both coercivity and corrosion resistance of Nd-Fe-B magnet are distinctly enhanced. • Ni alloying lowers melting point of Pr-Tb-Cu and deepens the infiltration of Tb. • Ni alloying results in higher potential of grain boundary than that of 2:14:1 phase. • Scanning Kelvin probe force microscopy was used to measure local potential. [ABSTRACT FROM AUTHOR]

• Compared to TI120, MI120 and MI150 significantly increased grain yield and WUE. • MI90 ensured grain yield by significantly improving thousand grain weight. • Except for MI60, MI treatments significantly delayed the senescence of flag leaf during grain filling. • MI treatments ensured the water supply in the mainly root distribution zone of wheat. • MI with reducing irrigation promoted water consumption of the deep soil profile. It's very important to guarantee the wheat production and improve water productivity in the North China Plain (NCP). In order to reduce irrigation and ensure the crop production in the NCP, a two-year field experiment of winter wheat was conducted in 2016–2018 using micro-sprinkling irrigation including different irrigation amount treatments (60 mm, MI60; 90 mm, MI90; 120 mm, MI120; and 150 mm, MI150), and the local traditional water-saving and productive flooding irrigation method (TI120) was as a control. The grain yield (GY), dry matter accumulation (DM), root system distribution and water utilization were investigated. The results showed that, the GY of MI60 decreased by 5.1–13.4% compared with TI120; GY of MI90 was comparable with TI120, while that of MI120 and MI150 increased significantly. The higher GY in micro-sprinkling treatments was mainly due to the significant increase of 1,000-grain weight (TGW), which was the result of the significant delay of the senescence in flag leaves during grain filling and then the increase in the post-anthesis DM. In addition, the roots mainly distributed in the 0−60 cm soil profile, and micro-sprinkling ensured the soil water supply in this areas at the critical growth stages; what's more, micro-sprinkling with reducing irrigation treatments significantly promoted the growth of root system to the deep soil layer, which improved the absorption and utilization of moisture stored in soil. Compared with TI120, the same irrigation amount treatment under micro-sprinkling (MI120) significantly increased water use efficiency (WUE) due to higher GY and lower seasonal evapotranspiration (ET); the 125% irrigation amount treatment (MI150) increased WUE due to higher GY and comparable ET; the 75% irrigation amount treatment (MI90) obtained the similar WUE to TI120; the 50% irrigation amount treatment (MI60) got similar or lower WUE to TI120. Overall, suitable reduction of irrigation amount under micro-sprinkling (MI90) can ensure the grain yield of winter wheat and efficient utilization of irrigation water in the NCP. [ABSTRACT FROM AUTHOR]