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The rapid development of miniaturized, high-frequency, and highly integrated microelectronic devices has brought about critical issues in electromagnetic compatibility and thermal management. In recent years, there has been significant interest in lightweight polymer-based composites that offer both electromagnetic interference (EMI) shielding and thermal conductivity. One promising approach involves constructing three-dimensional (3D) interconnection networks using functional fillers in the polymer matrix. These networks have been proven effective in enhancing the thermal and electrical conductivity of the composites. This mini-review focuses on the preparation and properties of 3D network-reinforced polymer composites, specifically those incorporating metal, carbon, ceramic, and hybrid networks. By comparing the effects of different filler types and distribution on the composite materials, the advantages of 3D interconnected conductive networks in polymer composites are highlighted. Additionally, this review addresses the challenges faced in the field of multifunctional thermal management and electromagnetic protection materials and provides insights into future development trends and application prospects of 3D structured composites. [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]

In ternary nitrides, the Ga0.9Fe3.1N sample has ultimately been prepared through solid‐gas preparation for the gallium‐richest phase GaFe3N. The substitution of gallium atoms for iron atoms weakens the saturation magnetization of ferromagnetic γʹ‐Fe4N and induces the transmission from ferromagnetism to antiferromagnetism. A new magnetic behavior, defined as the spin glassy magnetic state, has been observed in the temperature‐dependent magnetic performance measurement process for Ga0.9Fe3.1N. The magnetic competition between ferromagnetic and antiferromagnetic Fe–Fe bonds will lead to the spin frustration of the magnetic system. And even the positional disorders caused by substitution, will all be responsible for the spin glassy behavior in Ga0.9Fe3.1N. [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]

Background: The efficacy of preoperative biliary drainage (PBD) has been debated for several decades, and yet indications for PBD remain controversial. The aim of this study was to compare the postoperative morbidity and mortality in patients with malignant obstructive jaundice undergoing direct surgery versus surgery with PBD. Methods: All consecutive patients with malignant obstructive jaundice who underwent radical resection between June 2017 and December 2019 at Zhongshan Hospital were analyzed retrospectively. The study population was divided into two groups: PBD group (PG) and direct surgery group (DG). The subgroups were chosen based on the site of obstruction. Perioperative indicators and postoperative complications were compared and analyzed. Results: A total of 290 patients were analyzed. Postoperative complications occurred in 134 patients (46.4%). Patients in the PG group had a lower overall rate of postoperative complications compared with the DG group, with perioperative total bilirubin (TB) identified as an independent risk factor in multivariate analysis (hazard ratio = 1.004; 95% confidence interval 1.001–1.007; P = 0.017). Subgroup analysis showed that PBD reduced the complication rate in patients with proximal obstruction. In the proximal-obstruction subgroup, a preoperative TB level > 162 μmol/L predicted postoperative complications. Conclusions: PBD may reduce the overall rate of postoperative complications among patients with proximal malignant obstructive jaundice. Trial registration: ClinicalTrials.gov, 2018ZSLC 24. Registered May 17, 2018, https://clinicaltrials.gov/. [ABSTRACT FROM AUTHOR]

Background: Gallbladder cancer (GC) is a malignant disease characterized with highly cellular heterogeneity and poor prognosis. Determining the intratumoral heterogeneity and microenvironment (TME) can provide novel therapeutic strategies for GC. Methods: We performed the single‐cell RNA sequencing on the primary and lymph node metastatic gallbladder tumors and the adjacent normal tissues of five patients. The transcriptomic atlas and ligand–receptor‐based intercellular communication networks of the single cells were characterized. Results: The transcriptomic landscape of 24,887 single cells was obtained and characterized as 10 cellular clusters, including epithelial, neuroendocrine tumor cells, T&NK cells, B cells, RGS5+ fibroblasts, POSTN+ fibroblasts, PDGFRA+ fibroblasts, endothelial, myeloid cells, and mast cells. Different types of GC harbored distinct epithelial tumor subpopulations, and squamous cell carcinoma could be differentiated from adenocarcinoma cells. Abundant immune cells infiltrated into adenocarcinoma and squamous cell carcinoma, rather than neuroendocrine neoplasms, which showed significant enrichment of stromal cells. CD4+/FOXP3+ T‐reg and CD4+/CXCL13+ T helper cells with higher exhausting biomarkers, as well as a dynamic lineage transition of tumor‐associated macrophages from CCL20hi/CD163lo, CCL20lo/CD163hi to APOE+, were identified in GC tissues, suggesting the immunosuppressive and tumor‐promoting status of immune cells in TME. Two distinct endothelial cells (KDR+ and ACKR1+), which were involved in angiogenesis and lymphangiogenesis, showed remarkable ligand–receptor interactions with primary GC cells and macrophages in gallbladder tumors. Conclusions: This study reveals a widespread reprogramming across multiple cell populations in GC progression, dissects the cellular heterogeneity and interactions in gallbladder TME, and provides potential therapeutic targets for GC. [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]

Background: Gallstones are the cause of a majority of biliary tract discomfort. Although many community-based studies have addressed the risk factors for gallstone disease (GSD), little is known about GSD prevalence and risk factors in Chinese populations. Methods: From January 2014 to January 2015, participants (N = 2,068,523) were recruited by Meinian Onehealth Healthcare Co., Ltd. They received a physical examination, and GSD was determined by ultrasound. Results: The prevalence of GSD was 8.1%. Risks of GSD were similar between males and females in all age groups. Risk factors for gallstones include body mass index, waist circumference, waist-to-hip ratio, and physical activity, as well as biological factors such as age, sex, and elevated blood lipid levels. Serum lipid levels of GSD were statistically different from controls in total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (H-DL), low-density lipoprotein cholesterol (LDL), and apolipoprotein B (APOB). Furthermore, TC > 5.00 mmol/L, TG > 1.39 mmol/L, HDL < 1.19 mmol/L, LDL > 3.04 mmol/L, and APOB > 0.97 mmol/L were risk factors for gallstones. Conclusions: Serum lipid levels are associated with GSD. TC, TG, LDL, and APOB are risk factors, while HDL is a protective factor. [ABSTRACT FROM AUTHOR]

Background: The distant metastasis (DM) mode and treatment efficacies in the advanced biliary tract cancer (BTC) were obscure, and a credible evaluation is urgently needed. Method: A total of 6348 advanced BTC patients (ICC, intrahepatic cholangiocarcinoma, n = 1762; PHCC, perihilar cholangiocarcinoma, n = 1103; GBC, gallbladder cancer, n = 2580; DCC, distal cholangiocarcinoma, n = 538; AVC, carcinoma of Vater ampulla, n = 365) were enrolled from the Surveillance, Epidemiology, and End Results (SEER) database. Propensity score matching (PSM) process was carried out for less bias. Result: The proportion of M1 patients in each subtype at first diagnosis was 26.4% (ICC), 37.2% (PHCC), 41. 0% (GBC), 24.5% (DCC), and 12.7% (AVC), and the constitution of DM sites in different subtypes varied apparently. Moreover, the survival of metastasis sites was different (P <.05 in all the subtypes) where the multi‐metastasis and distant lymph node (dLN) only always indicated the worst and best prognosis, respectively. Chemotherapy presented the most significant survival impact with the lowest hazard ratio by multivariate cox model and still provided a survival improvement after PSM (all P <.001) in all subtypes. However, the median months manifested different between patients with and without chemotherapy among the subtypes (ICC, from 5 to 9; PHCC, from 6 to 10; AVC, from 4 to 9; GBC, from 6 to 7; DCC from 6 to 8). Conclusion: We provided a landscape about the detailed DM mode of the advanced BTC in a large population, found the survival differences among DM sites, and revealed the different chemotherapy efficacies in the BTC subtypes. [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]

Background: The prognostic benefits and safety of extended lymphadenectomy for hilar cholangiocarcinoma remain uncertain. The available evidence is still insufficient concerning its retrospective aspect. The aim of this study is to explore the clinical effect and safety of extended lymphadenectomy compared to regional lymphadenectomy in patients with hilar cholangiocarcinoma.Methods: The Relay-HC trial is a prospective, multicenter, and randomized controlled trial. Seven hundred and thirty-four eligible patients with resectable perihilar cholangiocarcinoma across 15 tertiary hospitals in China will be randomly assigned (1:1) to receive either regional lymphadenectomy or extended lymphadenectomy. The primary objective is to determine the overall survival after the two approaches. Secondary objectives of the study include the evaluation of perioperative mortality, postoperative complication, and disease-free survival. This study has been approved by the ethics committee of each participating hospital.Discussion: The Relay-HC trial is designed to investigate the prognostic benefits and safety of expanded lymphadenectomy for hilar cholangiocarcinoma. Currently, it has never been investigated in a prospective randomized controlled clinical trial.Trial Registration: Chinese Clinical Trial Registry (ChiCTR), ChiCTR1800015688 . Registered on 15 April 2018. [ABSTRACT FROM AUTHOR]

Background: Recent studies have reported TIMs play an important role in tumors progression or regression, but the effect of TIMs in biliary tract cancer remains unclear. The aim of this study is to investigate the prognostic value of tumor infiltrating mast cells (TIMs) and its influence on gemcitabine-based adjuvant chemotherapy (ACT) benefits in biliary tract cancer patients after surgery.Methods: TIMs were evaluated by immunohistochemical staining of tryptase in 250 patients with resected gallbladder carcinoma (GBC) or extrahepatic bile duct carcinoma (EBDC) from Zhongshan Hospital. The relationships between TIMs and clinicopathological factors and postoperative prognosis were analyzed respectively.Results: High TIMs infiltration was significantly correlated with prolonged overall survival (OS). Furthermore, multivariate analysis indicated TNM stage and TIMs as independent prognostic factors for OS. Patients with high TIMs infiltration appeared to significantly benefit from Gemcitabine-based ACT in the discovery and validation cohorts. Spearman analysis identified that TIMs infiltration were positively correlated with anti-tumor CD8+ T cells.Conclusion: TIMs infiltration is an independent favorable prognostic factor in GBC and EBDC patients, which could better stratify patients with different prognosis and predict benefit from gemcitabine-based ACT. [ABSTRACT FROM AUTHOR]