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Despite being a common therapy for hepatocellular carcinoma (HCC), insufficient thermal ablation can leave behind tumor residues that can cause recurrence. This is believed to augment M2 inflammatory macrophages that usually play a pro-tumorigenic role. To address this problem, we designed d -mannose-chelated iron oxide nanoparticles (man-IONPs) to polarize M2-like macrophages into the antitumor M1 phenotype. In vitro and in vivo experiments demonstrated that man-IONPs specifically targeted M2-like macrophages and accumulated in peri-ablation zones after macrophage infiltration was augmented under insufficient microwave ablation (MWA). The nanoparticles simultaneously induced polarization of pro-tumorigenic M2 macrophages into antitumor M1 phenotypes, enabling the transformation of the immunosuppressive microenvironment into an immunoactivating one. Post-MWA macrophage polarization exerted robust inhibitory effects on HCC progression in a well-established orthotopic liver cancer mouse model. Thus, combining thermal ablation with man-IONPs can salvage residual tumors after insufficient MWA. These results have strong potential for clinical translation. Man-IONPs can target and polarize pro-tumorigenic M2-like macrophages into anti-tumor M1-like ones and mitigate suppressive immune microenvironment to inhibit the tumor recurrence after microwave ablation (MWA). [Display omitted] [ABSTRACT FROM AUTHOR]

• Multiple factors may contribute to dysphagia. • Risk prediction models can used to predict dysphagia risk for individual patients. • The Nomogram achieves both a high-prediction performance and actionability evaluation. Surveys based on western populations have identified many risk factors for dysphagia in older people, but the potential risk factors consistent with the demographic characteristics of older, hospitalized Chinese patients require further study. This single-center prospective study aimed to determine the incidence of dysphagia in western China, and to develop and validate a model to predict the risk of dysphagia among older patients. A total of 343 inpatients (aged ≥ 65 years without dysphagia and cognitive impairment) were included. A score ≥ 2 on the Eating Assessment Tool-10 was defined as dysphagia. After a six-month follow-up, 70 (20.4%) patients were found to have dysphagia. The final model included age, wearing dentures, activities of daily living, cerebral vascular disease, coronary heart disease, and malignancy. The developed model has high predictive accuracy and can be easily implemented in daily practice. [ABSTRACT FROM AUTHOR]

Vat photopolymerization 3D printing of Si 3 N 4 ceramics has attracted great attention recently. To overcome the low curing depth limitation caused by α-Si 3 N 4 , β-Si 3 N 4 with low absorbance and large particle size was selected in this paper. After printing, the effects of pressureless sintering temperatures on mechanical and dielectric properties were systematically investigated. At 1800 °C, the real permittivity of Si 3 N 4 ceramics was 7.37, and the maximum bending strength was 367 ± 75 MPa. Considering the application of Si 3 N 4 ceramics in radomes/windows, the dielectric constant of Si 3 N 4 ceramics should be further reduced. Therefore, the octet-truss lattice structure was introduced to optimize the porosity of ceramics. As the porosity increased from 25% to 36%, the real permittivity decreased from 5.56 to 4.42, and the bending strength ranged from 98 ± 7–62 ± 13 MPa. It shows that vat photopolymerization 3D printing can be a promising technology for the fabrication of wave-transparent Si 3 N 4 ceramics. [ABSTRACT FROM AUTHOR]

Pre-menopausal female patients have a prolonged survival than post-menopausal patients, indicating that estrogen and/or estrogen receptor (ER) may have some biological effects on prognosis. ER expression in cancer tissue has been reported to be a significant prognostic marker in multiple human cancers. However, the prognostic value of estrogen and/or ER on female patients with esophageal squamous cell carcinoma (ESCC) is rarely reported. The present study was undertaken to elucidate the associations of serum estradiol level, tissue estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ) expression with clinical response and reproductive factor changes in 387 female ESCC patients. Radioimmunoassay revealed that serum estradiol level was higher in pre-menopausal than those in peri -menopausal and post-menopausal patients. Furthermore, patients with higher serum estradiol level appeared to have a better survival. Immunostaining results suggested that ERα positive (+) expression was mainly located in cytoplasm of tumor cells with a positive rate of 69.9% and ERβ (+) was mainly located in nucleus of tumor cells with a positive rate of 64.9%. We did not find the relations of ER expression with tumor invasion (P > 0.05), lymph node metastasis (P > 0.05), TNM staging (P > 0.05) and treatment method (P > 0.05). Surprisingly, ERα (+) expression was higher in post-menopausal patients than those in pre-menopausal patients (P < 0.05). Patients with number of pregnancy ≥ 4 have a higher ERβ (+) expression than those patients with ≤ 3 (P < 0.05). Univariate and multivariate survival analysis showed that ERβ (+) expression in addition to ERα (−) expression are favorable prognostic markers in female ESCC patients (P < 0.05). Further related study is needed to in-depth explore the potential mechanisms of ERα and ERβ in survival of female patients with ESCC. [ABSTRACT FROM AUTHOR]

A novel green emitting long afterglow phosphor Li 2 Ca 0.4 Sr 0.6 SiO 4 :Tb 3+ was obtained via a high temperature solid-state reaction in air atmosphere. X-ray diffraction (XRD), photoluminescence spectroscope (PLS), long afterglow spectroscope (LAS) and thermal luminescence spectroscope (TLS) were performed to characterize the physical properties of the phosphors. Typical 5 D 4 - 7 F j transitions of Tb 3+ ions were detected by PL spectra, corresponding to CIE chromaticity coordinates of x =0.3456, y =0.5745. An optimal concentration of Tb 3+ in the substrate was determined as 0.8 at%. The Li 2 Ca 0.4 Sr 0.6 SiO 4 phosphors showed a typical afterglow behavior when the UV source was switched off. A typical triple exponential decay behavior was confirmed after fitting the experimental data. Thermal simulated luminescence study further indicated that the afterglow behavior of Li 2 Ca 0.4 Sr 0.6 SiO 4 :Tb 3+ phosphors was generated by the recombination of electrons with the holes resulted from the doping of rare-earth ions (Tb 3+ ) in Li 2 Ca 0.4 Sr 0.6 SiO 4 host. The long afterglow luminescence mechanism of Li 2 Ca 0.4 Sr 0.6 SiO 4 :Tb 3+ is illustrated and discussed in detail on the basis of experimental results. [ABSTRACT FROM AUTHOR]

Laser powder bed fusion (LPBF) process is a promising additive manufacturing technique to manufacture multi-material integrated parts with complex structures. In this paper, the multi-material structure of Ti6Al4V/AlSi10Mg is fabricated by LPBF, the interfacial characterization, interfacial reaction mechanism and mechanical properties of Ti/Al structure are investigated. Results show that continuous and excellent metallurgical bonding between Ti6Al4V and AlSi10Mg is obtained, and the width of interface zone is about 100 μm. The equiaxed grains of aluminum alloy at the interface show random crystallographic orientation, which is attributed to the thermal dynamics in the melt pool, thermal cycles during LPBF process and lower thermal conductivity of titanium alloy. The interfacial reaction layers are orderly from titanium alloy to the aluminum alloy consisting of Ti 3 Al, TiAl with nanoparticles Ti 5 Si 3 and rod-like TiAl 3. The segregated Si atoms react with the dissolution of Ti atoms in-situ to form Ti 5 Si 3 , meanwhile, a mass of Al atoms also react with Ti atoms to form TiAl. Namely, the TiAl phase forms in thin layer shape embedded with nanoparticles Ti 5 Si 3 through eutectic reaction near the fusion line at the interface. At the wall of eutectic production, the TiAl 3 phase nucleation and grow opposite to the heat dissipation direction and vertical to the fusion line. Outside the fusion line, the supersaturated solid α-Ti transforms to Ti 3 Al through the diffusion of Al atoms in the part of titanium alloy. During the interfacial reaction, in-situ generated nanoparticles Ti 5 Si 3 could improve the joint strength, and the tensile strength of Ti6Al4V/AlSi10Mg specimens reached 264.8 ± 22.4 MPa. The tensile specimens exhibit brittle fracture and two typical fracture morphologies appear on the fracture surface. • Ti/Al samples were fabricated by laser powder bed fusion (LPBF), and the microstructure at the interface was affected by the extremely fast cooling rate and thermal cycles of LPBF • The interfacial phases are formed by different mechanisms and they are orderly from titanium alloy to the aluminum alloy consist of Ti 3 Al, TiAl with nanoparticles Ti 5 Si 3 and rod-like TiAl 3. • The tensile strength of Ti/Al specimens reached 264.8 ± 22.4 MPa due to the in-situ generated nanoparticles Ti 5 Si 3. [ABSTRACT FROM AUTHOR]

Tunable photoluminescence of Tb 3+ -doped LiMgPO 4 (Tb 3+ :LiMgPO 4 ) phosphors with different Tb 3+ concentrations are successfully synthesized by a high temperature solid-state reaction routine. X-ray diffraction (XRD) and photoluminescent spectroscope (PLS) are employed to characterize the phosphors. It is found that a suitable firing temperature is important for the synthesis of the phosphors, and pure phase material can only be obtained around 900 °C. PL spectra reveals typical 5 D 4 to 7 F j energy transition of Tb 3+ ions, and the emission colors varied from red to green with Tb 3+ concentration increasing, which is caused by the concentration quenching of Tb 3+ emission centers in the LiMgPO 4 matrix. The emissions peaking at 591, 619 and 695 nm are quenched at concentration of 1.5%, while the emissions at 489 nm and 543 nm are quenched at concentration of 8%. Further analysis of the data reveals two different energy transfer mechanisms for the five emission bands. The dipole–dipole model is proposed for the energy transfer of the red bands peaking at 694 nm, 619 nm and 591 nm, while the exchange interaction model is suggested for that of the green bands (543 nm and 489 nm), due to the different ion separations caused by different Tb concentrations. [ABSTRACT FROM AUTHOR]

Nowadays, Ni-rich cathodes act as a strong contender for high performance lithium-ion batteries cathodes due to their high capacities. Rapid capacity degradation and poor rate performance at high working voltages hinder their commercialization. This study reports a strategy for Ta5+ doping modification in LiNi 0.90 Co 0.04 Mn 0.03 Al 0.03 O 2 (NCMA) cathode via a solid-state route. This study confirmed that the introduction of strong Ta–O bond is beneficial to degrade H2–H3 phase transition during cycling. Subsequently, the polarization of electrodes and internal resistance have been alleviated since the H2–H3 phase transition of the Ta-doped NCMA cathode is suppressed, which eventually leads to a high cyclability. Moreover, it also confirmed that the diffusion of Li ions has been accelerated since the space of Li layer is enhanced. As a consequence, the Ta-NCMA cathode displays a high initial discharge capacity of 222.6 mA h·g−1 and outperforms the benchmarking cathodes in 100th capacity retention (from 43.7% to 91.8%) between 2.8 and 4.5 V. Besides, compared to pristine NCMA cathodes, the rate capability of Ta5+-doped NCMA cathodes cycling at 5C also increase from 112.2 mA h·g−1 to 167.2 mA h·g−1. Hence, Ta doped Ni-rich cathode should be a potential cathode to realize both high capacity and stability structure. [ABSTRACT FROM AUTHOR]

Abstract: The electronic structures of a LiFePO4 (010) surface adsorbed with C are studied by a first-principles method based on DFT. The results show that the system is more stable when the LiFePO4 (010) surface is cut through Li atoms. PDOS analysis shows that the electronic structure of atoms in the sub-surface is similar to that of atoms in the bulk. The unpaired electrons in Fe-d orbital play a key role in the changes in the microelectronic structure; these changes lower the band gap and generate new bands that favor the transfer of electrons. Atom C reacts with Fe by chemisorptions when C is adsorbed on the outermost layer. Therefore, the materials may have better electrochemical properties by the improvement of diffusion of both electrons and Li ions when limiting the crystal growth with C coating. [Copyright &y& Elsevier]

Abstract: Molecular dynamics technique has been employed to investigate the relationship between the intrinsic structure and transport properties of lithium ions in LiFePO4 cathode materials. The results show that it is more favorable for Li ion diffusion when crystalline LiFePO4 grows along specific [100] directions, which may cause higher lithium diffusivity through a one dimensional [010] migration path. The change of Li ion diffusivity with temperature reveals that higher temperatures result in higher disorder of the atoms (or ions) and makes Li–O bonding relatively weaker, suggesting that Li diffusion is influenced by the microstructure of LiFePO4, particularly the bonding strength between Li and O atoms. [Copyright &y& Elsevier]

Abstract: LiFePO4 has become a highly promising cathode material for use in the next generation of lithium-ion batteries, in which metal-doping is typically employed to improve the electrochemical properties. However, it is always difficult to resolve the issue that how the doping element and its position cause the microstructural changes and eventually influence the material properties. In this work, the X-ray diffraction (XRD) patterns of a series of metal-doped LiFePO4 were simulated by software MS Reflex to investigate those factors since XRD is a typical technique for the study of crystal structures. The effect of simulation conditions, doping position, and types of doping elements were discussed. The results revealed that: (1) the suitable step size should be 0.02° or less, and the simulation position had little influence on the XRD pattern; (2) the peak intensity changed with doping position, and had been affected more evidently at the Li-site compare with the Fe-site; (3) there was a close relationship between the doping elements and peak intensities in XRD patterns, and the variation degree of the peak intensity increased linearly with the atomic number of doping elements. [ABSTRACT FROM AUTHOR]

Herein, redshifted long persistent LiMg x Sr 4- x -2 y (BO 3) 3 : y Eu2+, Dy3+(Nd3+) phosphors are successfully prepared in a reducing atmosphere using a high-temperature solid-state process. The emission of phosphors displays redshift characteristics between 633 and 660 nm with an increase in the concentration of Mg2+ substitution, primarily attributed to enhanced energy level splitting of Eu2+ after Mg2+ replacement. The afterglow performance of LiMg 0.6 Sr 3.4-2 y (BO 3) 3 : y Eu2+, Dy3+ (Nd3+) samples is enhanced with increase in concentrations of the doped rare-earth ions. An optimal concentration of 6%, the best afterglow performance was achieved because high concentration traps with suitable energy levels were developed; this was confirmed using afterglow measurements and thermoluminescence tests. The Nd3+ codoped phosphor shows improved afterglow performance compared with the Dy3+ codoped phosphor at the same doping concentration, which can be attributed to Nd3+ can easily be incorporated into the borate lattice that generates electron traps with high concentration. [ABSTRACT FROM AUTHOR]

Vat photopolymerization 3D printing provides a novel approach for preparing broadband wave-transparent Si 3 N 4 /β-SiAlON composite ceramics. This paper oxidized raw powder to introduce low dielectric phases (SiO 2) and overcome the low curing depth of α-Si 3 N 4. The solid content of oxidized α-Si 3 N 4 was increased to 50 vol% for the first time by modification with dispersant. The selected print thickness of 50 μm was the highest known for Si 3 N 4 vat photopolymerization 3D printing, greatly improving printing efficiency. Finally, Si 3 N 4 /β-SiAlON composite ceramics were sintered in the range of 1600-1800 °C, and the mechanical and dielectric properties were systematically studied. The composite ceramics sintering at 1780 °C had a maximum bending strength of 236 ± 16 MPa, and the real permittivity was 4.83. At 1800 °C the porosity increased resulting in bending strength decreased to 109 ± 4 MPa, and the real permittivity to 3.23. This study filled the gap in the post-treatment of oxidized α-Si 3 N 4 and guided the application of Si 3 N 4 /β-SiAlON composite ceramics in the field of wave-transparent. [ABSTRACT FROM AUTHOR]