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Low-dielectric constant polymers are widely used in various microelectronic materials. With the development of 5G communication technology, there is an urgent need for polymer materials with low dielectric constant at high frequency, good thermal resistance, and mechanical properties. In this study, four novel poly (aryl ether ketone) (PAEK) containing different numbers of methylene groups were synthesized via nucleophilic polycondensation reaction. At 10 GHz, these polymer films exhibit excellent dielectric properties with dielectric constants as low as 2.76. The relationship between the dielectric constant and the number of methylene groups is illustrated by constructing the amorphous accumulation cell model. In addition, methylene groups provided the polymer with favorable mechanical performance, including Young's modulus in the range of 2.17–2.21 GPa, the tensile strength from 82.0 to 88.5 MPa and the elongation at the break achieved 7.94%, respectively. Simultaneously, the polymer maintains good thermal resistance with a glass transition temperature (Tg) reaching 216 °C. The result indicates that the obtained novel PAEK is potentially valuable in the field of high-frequency communications. [ABSTRACT FROM AUTHOR]

Multilevel boost converter is a multi-input multi-output nonlinear strongly coupled system. There is a coupling relationship between flying capacitor voltages and output voltage. In this paper, an optimal control method for n + 1-level boost converter based on exact feedback linearization and decoupling is proposed. The flying capacitor voltages and energy function are selected as the output functions to linearize and decouple the original system into n − 1 first-order subsystems and a second-order subsystem. Based on the optimal control theory, flying capacitor voltage balancing controllers are designed for n − 1 first-order subsystems, and an output voltage regulating controller is designed for the second-order subsystem. A five-level boost converter control system is verified by numerical simulation and a three-level boost converter control system is verified by experiment. Simulation and experimental results show that the proposed control strategy has better dynamic regulation performance and stronger robustness than PI decoupling control strategy based on small-signal model. [ABSTRACT FROM AUTHOR]

[Display omitted] • The three novel quinoxaline-based PAEs have been successfully prepared. • PAE films exhibit ultra-low D k (2.45–2.87) and D f (0.0019–0.0057) at high frequency. • PAEs show excellent hydrophobic, solubility and thermal properties. With the rapid growth of 5G communication technology, low-dielectric materials can decrease the loss of the signal during transmission. Hence, there is an urgent need to develop high-performance materials with low dielectric constant (D k) and dielectric loss (D f) at high frequency. In this study, we propose a strategy that combines bulk rigid quinoxaline structure and low polarizability trifluoromethyl group to prepare poly (aryl ether)s (PAEs) with low D k and D f at high frequencies. The effect of methyl substituents on the properties of PAEs was focuses on investigated. Accordingly, three difluoro-monomers containing quinoxaline structures were designed and prepared and novel quinoxaline-based PAEs with different numbers of methyl substituents were synthesized by nucleophilic condensation reactions with the bisphenol monomer hexafluorobisphenol A (BP6F). Test results that the resultant PAEs exhibited excellent thermal and solubility properties, with 5 % thermal decomposition temperatures (T d5%) in the range of 500−515 °C and glass transition temperatures (T g) reaching 225 °C. Furthermore, these PAE films show outstanding optical transparency, with cut-off wavelengths of 398−400 nm and above 87 % transmission at 800 nm. Most importantly, the novel PAE films possess ultra-low D k and D f , with the lowest values reaching 2.45 and 0.0024 at 10 GHz and maintain low water absorption (0.53–0.63 %). The excellent properties of novel quinoxaline-based PAEs provide its application potential in the field of high-frequency communications. [ABSTRACT FROM AUTHOR]

Salinity is an important environmental factor in microbial ecology for affecting the microbial communities in diverse environments. Understanding the salinity adaptation mechanisms of a microbial community is a significant issue, while most previous studies only covered a narrow salinity range. Here, variations in seawater prokaryotic communities during the whole salt drying progression (salinity from 3% to 25%) were investigated. According to high‐throughput sequencing results, the diversity, composition, and function of seawater prokaryotic communities varied significantly along the salinity gradient, expressing as decreased diversity, enrichment of some halophilic archaea, and powerful nitrate reduction in samples with high salt concentrations. More importantly, a sudden and dramatic alteration of prokaryotic communities was observed when salinity reached 16%, which was recognized as the change point. Combined with the results of network analysis, we found the increasing of complexity but decreasing of stability in prokaryotic communities when salinity exceeded the change point. Moreover, prokaryotic communities became more deterministic when salinity exceeded the change point due to the niche adaptation of halophilic species. Our study showed that substantial variations in seawater prokaryotic communities along an extremely wide salinity gradient, and also explored the underlying mechanisms regulating these changes. [ABSTRACT FROM AUTHOR]

Background: Lung cancer is cancer with the highest morbidity and mortality in the world and poses a serious threat to human health. Therefore, discovering new treatments is urgently needed to improve lung cancer prognosis. Small molecule inhibitors targeting the ubiquitin-proteasome system have achieved great success, in which deubiquitinase inhibitors have broad clinical applications. The deubiquitylase OTUD3 was reported to promote lung tumorigenesis by stabilizing oncoprotein GRP78, implying that inhibition of OTUD3 may be a therapeutic strategy for lung cancer. Results: In this study, we identified a small molecule inhibitor of OTUD3, Rolapitant, by computer-aided virtual screening and biological experimental verification from FDA-approved drugs library. Rolapitant inhibited the proliferation of lung cancer cells by inhibiting deubiquitinating activity of OTUD3. Quantitative proteomic profiling indicated that Rolapitant significantly upregulated the expression of death receptor 5 (DR5). Rolapitant also promoted lung cancer cell apoptosis through upregulating cell surface expression of DR5 and enhanced TRAIL-induced apoptosis. Mechanistically, Rolapitant directly targeted the OTUD3-GRP78 axis to trigger endoplasmic reticulum (ER) stress-C/EBP homologous protein (CHOP)-DR5 signaling, sensitizing lung cancer cells to TRAIL-induced apoptosis. In the vivo assays, Rolapitant suppressed the growth of lung cancer xenografts in immunocompromised mice at suitable dosages without apparent toxicity. Conclusion: In summary, the present study identifies Rolapitant as a novel inhibitor of deubiquitinase OTUD3 and establishes that the OTUD3-GRP78 axis is a potential therapeutic target for lung cancer. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the effects of Bacillus licheniformis and combined herbs extracts on the physiological and immune characteristics, intestinal microbiota, and vibriosis resistance of sea cucumber Apostichopus japonicus. The sea cucumbers were fed with basal diets supplemented with B. licheniformis (B group), combined herbs extracts (C group), or both (BC group). The BC group exhibited the better growth performance and higher digestive and immune enzyme activities, whereas the lowest parameters appeared in the control group. This revealed that dietary B. licheniformis and combined herbs extracts in combination could improve digestion, food intake, phosphatase-responsiveness, and oxidation resistance more efficiently compared with the other groups. The BC group was also more capable of regulating intestinal flora balance of sea cucumbers by increasing the beneficial bacteria related to energy synthesis and metabolic conversion, and inhibiting the potential pathogens associated with organic damage and metabolic disorders. Furthermore, the BC group showed greater ability of improving disease resistance by reducing the cumulative mortality rates and the counts of Vibrio splendidus. These results collectively demonstrated that dietary B. licheniformis and combined herbs extracts could improve the physiological and immune parameters, optimize the microbial community, and enhance the resistance to vibriosis of sea cucumbers, and the health-promoting effects were more obvious by supplying them in combination. [ABSTRACT FROM AUTHOR]

Aquaculture pond sediments have a notable influence on the ecosystem balance and farmed animal health. In this study, microalgal-bacterial immobilization (MBI) was designed to improve aquaculture pond sediments via synergistic interactions. The physicochemical characteristics, bacterial communities, and the removal efficiencies of emerging pollutants were systematically investigated. The consortium containing diatom Navicula seminulum and Alcaligenes faecalis was cultivated and established in the free and immobilized forms for evaluating the treatment performance. The results indicated that the immobilized group exhibited superior performance in controlling nutrient pollutants, shaping and optimizing the bacterial community compositions with the enrichment of functional bacteria. Additionally, it showed a stronger positive correlation between the bacterial community shifts and nutrient pollutants removal compared to free cells. Furthermore, the immobilized system maintained the higher removal performance of emerging pollutants (heavy metals, antibiotics, and pathogenic Vibrios) than free group. These findings confirmed that the employment of immobilized N. seminulum and A. faecalis produced more synergistic benefits and exerted more improvements than free cells in ameliorating aquaculture pond sediments, suggesting the potential for engineering application of functional microalgal-bacterial consortium in aquaculture. [Display omitted] • The cooperative interactions of MBI for reducing nutrient pollutants were explored. • MBI performed better in improving physicochemical properties than free system. • The bacterial communities were shaped and optimized by MBI more significantly. • MBI exhibited a higher emerging pollutants removal performance than free system. [ABSTRACT FROM AUTHOR]

The placenta becomes one of the most diversified organs during placental mammal radiation. The main in vitro model for studying mouse trophoblast development is the 2D differentiation model of trophoblast stem cells, which is highly skewed to certain lineages and thus hampers systematic screens. Here, we established culture conditions for the establishment, maintenance, and differentiation of murine trophoblast organoids. Murine trophoblast organoids under the maintenance condition contain stem cell-like populations, whereas differentiated organoids possess various trophoblasts resembling placental ones in vivo. Ablation of Nubpl or Gcm1 in trophoblast organoids recapitulated their deficiency phenotypes in vivo , suggesting that those organoids are valid in vitro models for trophoblast development. Importantly, we performed an efficient CRISPR-Cas9 screening in mouse trophoblast organoids using a focused sgRNA (single guide RNA) library targeting G protein-coupled receptors. Together, our results establish an organoid model to investigate mouse trophoblast development and a practicable approach to performing forward screening in trophoblast lineages. [Display omitted] • Murine trophoblast organoids can be derived from placentae or trophoblast stem cells • Murine trophoblast organoids exhibit features of their placental trophoblast counterparts • Ablation of essential genes in trophoblast organoids recapitulates in vivo placental defects • Murine trophoblast organoids can be used for CRISPR-Cas9 screening Mao, Ye, Xu, Jiang et al. established murine trophoblast organoids, which can be used to model mouse placental development and perform high-throughput genetic screening in a dish. [ABSTRACT FROM AUTHOR]

Silicon monoxide (SiO) is a promising anode material for lithium-ion batteries (LIBs) due to its relatively low volume change and superior cycling performance compared to silicon (Si). However, its low initial Coulombic efficiency (ICE) should be improved when the addition of SiO is higher than 5 wt% in graphite. Many prelithiation attempts have been made to improve its ICE, among which chemical prelithiation is widely used. However, the complex microstructures of prelithiated SiO (pre-SiO) hinder exploring the interconnection between microstructure and composition changes with its electrochemical performance. The size of Si nanodomains embedded in pre-SiO plays a crucial role in electrochemical performance. Herein, samples with different sizes of Si nanodomains are prepared via regulating the degree of prelithiation. Then the structure, composition evolutions and the size effect of Si nanodomains on the electrochemical performance are well investigated. The Si nanodomain size grows with the incremental prelithiation degree, leading to more capacity degradation. It is indicated that prelithiation promotes the growth of Si nanodomains and an appropriate Si nanodomain size of ∼10 nm is essential to retard volume expansion thus improving the cyclability. These results give fundamental insight into the pre-SiO for its future applications as the next-generation LIBs anodes. • Pre-SiO with different sizes of Si nanodomain were prepared via the Li/Si ratio. • The structure and composition content evolutions in pre-SiO were investigated. • The effect of Si nanodomain size on pre-SiO performance was investigated. • The appropriate size of Si nanodomain in pre-SiO boosts structural stability. [ABSTRACT FROM AUTHOR]

In recent years, sea cucumber has become a favorite healthcare food due to its characteristic prevention of cardiovascular diseases, suppression of tumors, as well as enhancement of immunity. In order to screen the anti-tumoral proteins or peptides from sea cucumber (Apostichopus japonicus), its cDNA library was analyzed, and a disintegrin-like and metalloproteinase with thrombospondin type 1 motif, member 13 (ADAMTS13)-like was found. ADAMTS13-like contains 10 thrombospondin 1 (TSP1) domains. Based on analysis of bioinformatics, the third TSP1 domain of this protein, which is further named Aj-Tspin, contains an arginine-glycine-aspartate (RGD) motif. Since our previous studies showed that the recombinant RGD-containing peptide from lampreys showed anti-tumoral activity, the third TSP1 domain of ADAMTS13-like was chosen to evaluate it's effect on tumor proliferation and metastasis, despite the fact it shares almost no homologue with disintegrins from other species. After artificial synthesis, its cDNA sequence, Aj-Tspin, which is composed of 56 amino acids, was subcloned into a pET23b vector and expressed as a recombinant Aj-Tspin (rAj-Tspin) in a soluble form with a molecular weight of 6.976 kDa. Through affinity chromatography, rAj-Tspin was purified as a single protein. Both anti-proliferation and immunofluorescence assays showed that rAj-Tspin suppressed the proliferation of Lewis lung carcinoma (LLC) cells through apoptosis. Adhesion assay also displayed that rAj-Tspin inhibited the adhesion of LLC cells to ECM proteins, including fibronectin, laminin, vitronectin and collagen. Lastly, rAj-Tspin also suppressed the migration and invasion of LLC cells across the filter in transwells. Thus, the above indicates that rAj-Tspin might act as a potential anti-tumoral drug in the future and could also provide information on the nutritional value of sea cucumber. [ABSTRACT FROM AUTHOR]