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Digital light processing 3D printing can be applied to fabricate complex silicon nitride (Si 3 N 4) components. However, because of the surface hydroxyl groups and large refractive index, it is still a foremost challenge to realize a stable photosensitive Si 3 N 4 slurry with combined benefits of low viscosity and large curing depth. In this study, we propose a new formulation strategy to prepare Si 3 N 4 slurry. Starting from the optimization of monomer ratio, we have systematically optimized powder particle size, dispersant and photoinitiator on the rheological properties and curing properties of Si 3 N 4 slurry. Specifically, we have fabricated a stable photosensitive Si 3 N 4 slurry (48 vol%) with a viscosity of 2.09 Pa s (30 s−1), a critical curing energy of 126.09 mJ/cm2 and a maximum curing depth of 80 µm. Finally, based on this optimized slurry, we have successfully obtained complex Si 3 N 4 green body with no defect, which demonstrates great potential to fabricate arbitrary complex ceramic components for various applications. [ABSTRACT FROM AUTHOR]

• MXene/AgNWs aerogels with interpenetrating double-network structure were fabricated. • The porous structure contributes to higher attenuation of electromagnetic waves. • 3D network provides channel for electron and phonon transmission in epoxy composites. • The composites possess remarkable EMI SE and thermal conductivity. The novel multifunctional materials with anti-electromagnetic interference (EMI) and effective thermal management are ideal for modern electronic industry. Generally, the EMI shielding effectiveness (SE) and thermal conductivity (TC) of materials can be effectively enhanced by compounding with high electrically and thermally conductive fillers. However, it seems that the high-performance cannot be compensated without sacrificing the high fillers loading. Herein, from one-dimensional silver nanowires (AgNWs) and two-dimensional MXene, three-dimensional MXene/AgNWs aerogels were designed as electric and heat transferring skeletons for epoxy nanocomposites by directional-freezing and freeze-drying methods. The resultant MXene/AgNWs/Epoxy nanocomposites with a low MXene/AgNWs content of 8.2 wt% combine a high electrical conductivity of 1532 S/m, and an exceptional EMI SE value of 94.1 dB with 3 mm thickness at the X-band frequency, as well as an improved TC of 2.34 W/m·K. The fabricated MXene/AgNWs/Epoxy nanocomposites possess excellent comprehensive properties enable valuable applications in electronic devices for EMI shielding and thermal management. [ABSTRACT FROM AUTHOR]

• Polymer-matrix composites. • 3-Dimensional reinforcement. • Thermal properties. • Syntactic foams. • Hollow glass microspheres. Electronic packaging materials with low dielectric constant (D k) and high thermal conductivity (TC) are of vital importance in mitigating signal delay and enhancing heat dissipation efficiency in modern electronics. However, low D k and high TC are difficult to complement each other, because high TC filler usually possesses a high D k. Herein, we have newly designed a composite material simultaneously with low D k and high TC through hollow glass microspheres (HGMs), boron nitride particles, epoxy resin and reticulated porous ceramic (RPC). The composite material prepared by sintering HGMs and RPC is more effective in improving TC while keeping low D k. Specifically, the D k of the newly designed composite is lower than 3.0 with a large TC of 0.96 W/m·K. This new epoxy-matrix composite with both low D k and high TC can shed new light on designing electronic packaging materials for advanced miniaturized electronics. [ABSTRACT FROM AUTHOR]

For new-generation miniaturized and high-frequency electronics, it is of vital importance to develop advanced electronic packaging materials, which combine high electromagnetic interference (EMI) shielding effectiveness (SE) and efficient thermal management capabilities, including heat absorption, thermal conductivity (TC) and heat dissipation. However, high EMI SE and efficient thermal management usually cannot complement each other for the same packaging material, because EMI shielding devices convert electromagnetic radiation directly into heat consumption, leading to consequent severe challenge to dispose heat dissipation. Herein, we have newly developed a high-performance phase change composites, in which MXene is confined in shape-stabilized phase change material (PCM) for simultaneous achievement of high EMI SE and efficient thermal management. Regarding high EMI, MXene can effectively shield electromagnetic radiation by converting the radiation into heat consumption. As for thermal management, PCM enables efficient heat absorption via the phase change process, and MXene enhances the thermal conductivity (TC) of MXene/PCM composite to facilitate heat dissipation. As a result, our developed MXene/PCM composite can achieve a high EMI SE of 64.7 dB in X-band, with an improved TC of 0.74 W/m·K. Furthermore, the interlayer capillary effect of MXene inhibits the leakage of liquid PCM during the solid-liquid phase transition, which can maintain the PCM shape stability. Our newly-designed shape-stabilized MXene/PCM composites with high EMI SE and large TC shed new light on designing EMI shielding materials with prolonged exposure to electromagnetic radiation, which can be envisioned to exhibit vast implications for advanced new-generation miniaturized and high-frequency electronics. [Display omitted] [ABSTRACT FROM AUTHOR]

Nano-SiO 2 porous thermal insulating material (TIM) has drawn tremendous research interests due to its advantages of low density, high porosity and low thermal conductivity. However, its long-term stability in humid environment can be severely deteriorated by the high hydrophilicity resulting from tetrahedral coordination of oxygen and capillary effect of porous structure. It is still a great challenge to cost-effectively fabricate bulk TIM with superior hydrophobicity and consequent remarkable self-cleaning capability. Herein, via an oil-in-water microemulsion treatment, we have proposed a new strategy to construct 3D superior hydrophobic nano-SiO 2 porous TIM. The polymethylhydrosiloxane-modified TIM exhibits a large water contact angle of 166°, and corresponding excellent self-cleaning characteristic while maintaining low thermal conductivity of 0.031 W/m·K. Moreover, our high hydrophobicity of TIM exhibits excellent durability under high temperature up to 400 °C, high humidity of 100%, and chemical erosions. Detailed knowledge of the physical chemistry basis of the superior hydrophobic nano-SiO 2 porous TIM can provide great opportunity to fabricate advanced self-cleaning and heat insulating devices especially targeted for harsh environments. [ABSTRACT FROM AUTHOR]

The high integration density of microelectronic devices leads to local heat accumulation, and effective heat dissipation and signal transmission of packaging materials have become the primary issues to be solved. However, existing polymer materials have difficulty meeting the requirements due to their unsatisfactory thermal conductivity and thermal expansion properties. In this work, we proposed the use of digital light processing (DLP) printing technology to construct a triply periodic minimum surface (TPMS) skeleton, and a continuous and efficient heat conduction path was successfully constructed in epoxy resin by impregnating h-BN on the skeleton surface. When the loading of h-BN was 20 vol%, the thermal conductivity of the TPMS(SiO 2)@BN/EP(BN) composites was 1.86 W/(m·K), which was 786 % higher than that of pure epoxy resin. In addition, the thermal expansion coefficient of the composites decreased by more than 70 %. At the test frequencies of 3∼10 MHz, the composites showed stable dielectric properties, and the dielectric constant was always maintained in a low range, between 3.85 and 4.15. This work has realized the transformation of the method for constructing a heat conduction path from disordered to ordered and from random to repeatable. This provides a new strategy for the selection of microelectronic packaging materials. [ABSTRACT FROM AUTHOR]

We have optimized a CuO-doped silver paste to significantly improve the adhesion strength of silver thick film on AlN ceramic substrate, which can be widely applied in power electronic packaging applications. Via a combination of scanning electron microscope and X-ray diffraction, we have systematically studied the silver layer morphology on top of AlN ceramic substrate, and the interphases between the silver thick film and AlN substrate. Due to the CuAl 2 O 4 intermediate formed at the silver layer/AlN interface, the adhesion strength of silver thick film can be greatly improved. Particularly, the silver paste with 3 wt% nano-CuO sintered on AlN ceramic substrate exhibits high adhesion strength of 15.3 MPa with good electrical conductivity of 0.9 mΩ/□. [ABSTRACT FROM AUTHOR]

This paper presents that polyethylene glycol (PEG) synthesizes a form-stable phase change material (FS-PCM) with high thermal conductivity and considerable heat storage density. PEG was confined to the chain structure of epoxy resin (EP) via high-temperature melt blending and curing, which solves the leakage problem of PCMs during phase transformation. In order to increase the thermal conductivity and stability of the PEG/EP while maintaining good heat storage capacity and insulation ability, a low loading of reticulated porous Al 2 O 3 ceramic (RPC) was introduced into the PEG/EP matrix. RPC increases the thermal conductivity of FS-PCM by 5.5 times and the heat storage rate by 4 times. In addition, FS-PCM filled with 13.8 vol% RPCs has a coefficient of thermal expansion (CTE) of 80 ppm/K at 85–150 °C -a decrease of 62% over the matrix. Furthermore, the BN network is formed on RPC by vacuum impregnation technology, which further improves the thermal conductivity. This novel FS-PCM has excellent comprehensive properties and does not need for case package, indicating great prospects in thermal management and thermal storage. [ABSTRACT FROM AUTHOR]

Abstract: CD133+ tumor cells are responsible for the initiation, propagation and recurrence of tumors, which raises the question of how to effectively target CD133+ tumor cells. Arsenic trioxide (As2O3) has considerable efficacy in treating solid tumors with induction of apoptosis. Here, we found that purified CD133+ gallbladder carcinoma cells are highly resistant to conventional chemotherapy. However, As2O3 effectively induces CD133+ gallbladder carcinoma cells apoptosis. Treatment with As2O3 reduces CD133 expression at transcriptional levels. Furthermore, the ectopic expression of CD133 attenuated the apoptotic effect of As2O3 on cells through activation of AKT signaling pathways. Collectively, As2O3 effectively targets CD133 in gallbladder carcinoma, providing a new mechanism of As2O3-induced cell apoptosis and a better understanding of drug resistance in gallbladder carcinoma. [Copyright &y& Elsevier]

• B-site precursor method can effectively inhibit the appearance of second phase. • B-site precursor method can obtain high reactivity Mg 4 Nb 2 O 9 powders. • B-site precursor method can promote integrality of the crystal structure. Mg 4 Nb 2 O 9 ceramics have been prepared by B-site precursor method in this work. Experimental results demonstrate that the uniform particles-size distribution of Mg 4 Nb 2 O 9 powders can be obtained, which exhibit high reactivity to promote the grain growth of Mg 4 Nb 2 O 9 ceramics. Moreover, the Mg 4 Nb 2 O 9 ceramics via B-site precursor method can be sintered at a wide range of sintering temperature from 1275 to 1375 °C with single phase Mg 4 Nb 2 O 9 composition and high crystallinity. Compared to the conventional solid-state method, the Mg 4 Nb 2 O 9 ceramics prepared by B-site precursor method exhibit excellent Q × f value by above 168,756 GHz. [ABSTRACT FROM AUTHOR]

Gallbladder carcinoma (GBC) is a considerable challenge because of its high metastatic potential. The tumor microenvironment is characterized by nutrient starvation, which promotes tumor metastasis. Stathmin1, an important microtubuleregulating protein, is overexpressed and promotes metastasis in GBC. It remains unclear how the harsh tumor microenvironment regulates stathmin1 expression to affect GBC metastasis. We employed glucose deficiency to mimic nutrient starvation and found that glucose deficiency upregulated stathmin1 transcription. However, glucose deficiency also promoted p27 degradation. There was a significant negative correlation between stathmin1 and p27 protein levels under glucose deficiency. Further study revealed that, under glucose deficiency, human kinase interacting with stathmin (hKIS) induced phosphorylation at Ser10 of p27 and its translocation to the cytoplasm for degradation, which upregulated the transcription factor E2F1 to promote stathmin1 transcription. hKIS knockdown significantly inhibited p27 cytoplasmic translocation and its consequent degradation. Stathmin1 knockdown significantly inhibited GBC cell migration and invasion in vitro. Our study revealed the role of the hKIS/p27/E2F1 axis in upregulating stathmin1 transcription to promote GBC cell migration and invasion under glucose deficiency conditions • We model the nutrition starvation conditions with glucose deficiency; • We found increased levels of stathmin1 of GBC in nutrition starvation condition; • Glucose deficiency induced phosphorylation of p27Kip1 at Ser10 and consequently degradation; • Phosphorylation of p27 at Ser10 promoted GBC migration and invasion; • hKIS/p27/E2F1 axis regulated stathmin1 expression and GBC cell migration and invasion under glucose deficiency conditions. [ABSTRACT FROM AUTHOR]

B Introduction: b The 8 SP th sp edition of the AJCC staging system for gallbladder cancer (GBC) has been used in clinical practice, but we have found some deficiencies in the new edition. In our modified edition, N2 disease obtained a significant subdivision and reappraisal according to T stage, and the aberrant survival reversal of stage IIIA and stage IIIB was also corrected. [Extracted from the article]

B Introduction: b Despite the advantages of 3D laparoscopy was reported, the effect of 3D laparoscopy in choledocholithiasis remained unclear. B Conclusion: b 3D laparoscopy would significantly reduce operation time, blood loss and conversion rate in patients with moderate abdominal adhesions. [Extracted from the article]