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Poly(diethyl fumarate-co-methoxyethyl acrylate-co-vinyl chloroacetate) (PDEFMV), a novel bio-based elastomer with a saturated structure, was synthesized via redox emulsion polymerization. The glass-transition temperatures of PDEFMV, adjusted through the variation of the diethyl fumarate-to-methoxyethyl acrylate feeding ratio, ranged from −36.1 to −14.8 °C. The number-average molecular weights of PDEFMV ranged from 384,000 to 46,000 g/mol. In designing the molecular structure, vinyl chloroacetate was used to provide active sites for subsequent vulcanization and crosslinking. The active chlorine groups within the PDEFMV chain reacted with the crosslinking agent trithiocyanuric acid under high temperature and pressure to form a nonsulfur crosslinked three-dimensional network structure. To achieve the desired properties, carbon black (CB, N330) was incorporated to reinforce PDEFMV, leading to the formation of PDEFMV/CB composites. A comprehensive study was conducted on the high-temperature oil resistance of PDEFMV/CB composites. Following immersion in IRM903 oil at temperatures of 150 and 200 °C for 72 h, the mass and volume changes in PDEFMV/CB were lower than those observed in commercially available acrylate rubber (AR)/CB, indicating that PDEFMV exhibited superior oil resistance. Furthermore, the aging characteristics and mechanisms of oil resistance in the PDEFMV/CB and AR/CB composites were investigated at different temperatures (150, 200, and 250 °C). The results provide insights into the operational temperature ranges suitable for PDEFMV/CB and offer valuable guidance for potential industrial applications. [ABSTRACT FROM AUTHOR]

The present study aimed to evaluate the effects of zinc amino acid complexes on growth performance, tissue zinc concentration, and muscle development in broilers. A total of 504 day-old male arbor acres broilers were randomly divided into seven treatments (fed with a basal diet or a basal diet supplemented with 120 mg kg−1 Zn as ZnSO4, 30, 60, 90 or 120 mg kg−1 Zn as ZnN, or 30 mg kg−1 Zn as ZnA separately). Each group had six replicates, with 12 birds per replicate. The results showed that the addition of 60 mg kg−1 ZnN significantly increased (P < 0.05) the average daily gain (ADG) and breast muscle percentage of broilers. Zinc concentration of ZnN and ZnA added groups were higher than (P < 0.05) that in the Zn sulfate group under the same addition dose. Except for the 30 mg kg−1 ZnN group, the muscle fiber diameter and cross-sectional area (CSA) were significantly increased (P < 0.05) in the ZnN addition groups. Compared with the basal diet group, adding ZnN significantly increased (P < 0.05) the expression of MTOR, MYOD, and MYOG at day 21 and decreased (P < 0.05) the expression of Atrogin-1. The expression levels of AKT, MTOR, P70S6K, and MYOD were increased at day 42, while the expression levels of MuRF1 and Atrogin-1 were decreased. Adhesion, backbone regulation of actin, MAPK, mTOR, and AMPK were significantly enriched as indicated by KEGG pathway enrichment analysis. In conclusion, zinc amino acid complexes could improve growth performance, tissue zinc concentration, and regulate breast muscle development. [ABSTRACT FROM AUTHOR]

The high exciton binding energy and lack of a positive oxidation band potential restrict the photocatalytic CO2 reduction efficiency of lead-free Bi-based halide perovskites Cs3Bi2X9 (X = Br, I). In this study, a sequential growth method is presented to prepare a visible-light-driven (λ > 420 nm) Z-scheme heterojunction photocatalyst composed of BiVO4 nanocrystals decorated on a Cs3Bi2I9 nanosheet for photocatalytic CO2 reduction coupled with water oxidation. The Cs3Bi2I9/BiVO4 Z-scheme heterojunction photocatalyst is stable in the gas–solid photocatalytic CO2 reduction system, demonstrating a high visible-light-driven photocatalytic CO2-to-CO production rate of 17.5 μmol/(g·h), which is approximately three times that of pristine Cs3Bi2I9. The high efficiency of the Cs3Bi2I9/BiVO4 heterojunction was attributed to the improved charge separation in Cs3Bi2I9. Moreover, the Z-scheme charge-transfer pathway preserves the negative reduction potential of Cs3Bi2I9 and the positive oxidation potential of BiVO4. This study offers solid evidence of constructing Z-scheme heterojunctions to improve the photocatalytic performance of lead-free halide perovskites and would inspire more ideas for developing lead-free halide perovskite photocatalysts. [ABSTRACT FROM AUTHOR]

Metallic glass offers several advantages, including high strength, corrosion resistance, and low coercivity. In precision machining fields like optical devices, medical devices, and micro-electromechanical systems, Ti-based metallic glass offers more advantages than Fe- and Zr-based metallic glass. However, its current machinability poses a challenge in meeting the requirements of precision metallic glass parts. To obtain the best machining performance, a thermophysical model of the EDM drilling process was established to simulate the temperature distribution on the surface of metal glass workpiece during EDM drilling. In addition, a new systematic method is utilized to calculate the characteristics of important machining holes, such as inlet and outlet overcut and inlet and outlet edge deviation. In this investigation, the maximum relative overcut and edge deviation are 8.59% and 7.23%, respectively, relative to the electrode radius. To improve the machining quality and machining stability, the slit width should be kept at an ideal value. Therefore, the recommended discharge current is 4–5 A, pulse duration is 50 μ s, and pulse duty ratio is 0.2 - 0.3 when EDM drilling of amorphous alloy. Based on this, the EDM drilling analysis method by numerical and experimental investigation for titanium-based metallic glass is put forward, which provides scientific theoretical guidance for the EDM of drilling it. [ABSTRACT FROM AUTHOR]

Objective: To investigate the relationship between immunohistochemical characteristics and recurrence after complete remission (CR) with fertility preservation treatment in patients with endometrial cancer (EC) and endometrial atypical hyperplasia (AH). Methods: The clinical data and immunohistochemical results of 53 patients with EC and 68 patients with AH admitted to Peking University People's Hospital from January 2010 to January 2021 were retrospectively analyzed. Patients were divided into two groups according to whether recurrence after complete remission (CR): group 1: recurrence after CR; group 2: no recurrence after CR, for statistical analysis. Results: (1) The expression rate of ER in group 1 was lower than that in group 2, (P < 0.05). The expression rate of Ki-67 in group 1 was significantly higher than that in group 2, (P < 0.01). The expression rates of PR, P16, P53, and PTEN were not significantly different between the two groups (P > 0.05); (2) combination index ER/ Ki-67 row ROC curve analysis, there was a significant difference (P < 0.01), the best cut-off value was 3.55, sensitivity 0.730, specificity 1.000, Youden index 0.730. The 3-year RFS of high rate patients was 100%, and that of low rate patients was 42.3%, P < 0.01. Conclusions: The expression rate of Ki-67 is of great significance in predicting the recurrence of EC after fertility preservation therapy. The best cut-off value of combination index ER/ Ki-67 (3.55) was better than a single immunohistochemical marker in predicting recurrence of EC after fertility preservation treatment. [ABSTRACT FROM AUTHOR]

Owing to its attractive optical and electronic properties, silicon carbide is an emerging platform for integrated photonics. However an integral component of the platform is missing—an electro-optic modulator, a device which encodes electrical signals onto light. As a non-centrosymmetric crystal, silicon carbide exhibits the Pockels effect, yet a modulator has not been realized since the discovery of this effect more than three decades ago. Here we design, fabricate, and demonstrate a Pockels modulator in silicon carbide. Specifically, we realize a waveguide-integrated, small form-factor, gigahertz-bandwidth modulator that operates using complementary metal-oxide-semiconductor (CMOS)-level voltages on a thin film of silicon carbide on insulator. Our device is fabricated using a CMOS foundry compatible fabrication process and features no signal degradation, no presence of photorefractive effects, and stable operation at high optical intensities (913 kW/mm2), allowing for high optical signal-to-noise ratios for modern communications. Our work unites Pockels electro-optics with a CMOS foundry compatible platform in silicon carbide. Electro-optic modulator is used to encode electrical signals onto light. Here the authors demonstrate an electro-optic modulator, based on Silicon Carbide, which can be useful for quantum and optical communications. [ABSTRACT FROM AUTHOR]

We present a novel workflow for forecasting production in unconventional reservoirs using reduced-order models and machine-learning. Our physics-informed machine-learning workflow addresses the challenges to real-time reservoir management in unconventionals, namely the lack of data (i.e., the time-frame for which the wells have been producing), and the significant computational expense of high-fidelity modeling. We do this by applying the machine-learning paradigm of transfer learning, where we combine fast, but less accurate reduced-order models with slow, but accurate high-fidelity models. We use the Patzek model (Proc Natl Acad Sci 11:19731–19736, https://doi.org/10.1073/pnas.1313380110, 2013) as the reduced-order model to generate synthetic production data and supplement this data with synthetic production data obtained from high-fidelity discrete fracture network simulations of the site of interest. Our results demonstrate that training with low-fidelity models is not sufficient for accurate forecasting, but transfer learning is able to augment the knowledge and perform well once trained with the small set of results from the high-fidelity model. Such a physics-informed machine-learning (PIML) workflow, grounded in physics, is a viable candidate for real-time history matching and production forecasting in a fractured shale gas reservoir. [ABSTRACT FROM AUTHOR]

Two Co–Cr–O spinel catalysts with different stoichiometry were synthesized and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, N2 physisorption and temperature-programmed reduction in H2. Excess Co in Co1.5Cr1.5O4 existed as Co3+ that substituted for Cr3+ in the octahedral sites of the spinel lattice. High temperature treatment of the spinel catalysts in H2 resulted in stepwise reduction of Co3+ to Co2+ and eventually to Co metal. Both CoCr2O4 and Co1.5Cr1.5O4 catalysts were active and structurally stable in ethylene steam reforming under differential reaction conditions at 873 K, with the areal reforming rate over Co1.5Cr1.5O4 being one order-of-magnitude greater than that over CoCr2O4. The steady state reforming rate after oxidation was comparable to that over the fresh catalyst for both CoCr2O4 and Co1.5Cr1.5O4, indicating the stability of the spinel structure against reduction under steam reforming conditions. [ABSTRACT FROM AUTHOR]

A flexible, multi-site tactile and thermal sensor (MTTS) based on polyvinylidene fluoride (resolution 50 50) is reported. It can be used to implement spatial mapping caused by tactile and thermal events and record the two-dimensional motion trajectory of a tracked target object. The output voltage and current signal are recorded as a mapping by sensing the external pressure and thermal radiation stimulus, and the response distribution is dynamically observed on the three-dimensional interface. Through the mapping relationship between the established piezoelectric and pyroelectric signals, the piezoelectric component and the pyroelectric component are effectively extracted from the composite signals. The MTTS has a good sensitivity for tactile and thermal detection, and the electrodes have good synchronism. In addition, the signal interference is less than 9.5% and decreases as the pressure decreases after the distance between adjacent sites exceeds 200 mm. The integration of MTTS and signal processing units has potential applications in human-machine interaction systems, health status detection and smart assistive devices. [ABSTRACT FROM AUTHOR]

The complete genome of a bear picornavirus 1 (BePV-1) in the viscera of an Asian black bear (Ursus thibetanus) from China was characterized using viral metagenomics and RT-PCR/Sanger sequencing. The genome of BePV1 is 6703 nt long, contains a type-IV IRES 5'UTR with the '8-like' motif, encodes a 2053-aa-long polyprotein showing a 3-4-4 organization pattern and two 2A genes. BePV-1 showed the highest overall genome nucleotide sequence identity of 71.7% to a picornavirus genome from an Arctic ringed seal (Phoca hispida) from Canada, classified as a member of the species Aquamavirus A, currently the only one in the genus Aquamavirus. Phylogenetic and genetic distance analyses of P1 and 3D indicated that Asian bear picornavirus (aquamavirus B) represents the second sequenced member of the genus Aquamavirus. [ABSTRACT FROM AUTHOR]

Carbon nanotubes/graphene composites have superior mechanical, electrical and electrochemistry properties with carbon nanotubes as a hydrophobicity boosting agent. Their extraordinary hydrophobic performance is highly suitable for electrode applications in lithium ion batteries and supercapacitors which often employ organic electrolytes. Also the hydrophobic features enable the oil enrichment for the crude oil separation from seawater. The ever reported synthesis routes towards such a composite either involve complicated multi-step reactions, e.g., chemical vapor depositions, or lead to insufficient extrusion of carbon nanotubes in the chemical reductions of graphene oxide, e.g., fully embedding between the compact graphene oxide sheets. As a consequence, the formation of standalone carbon nanotubes over graphene sheets remains of high interests. Herein we use the facile flash light irradiation method to induce the reduction of graphene oxides in the presence of carbon nanotubes. Photographs, micrographs, X-ray diffraction, infrared spectroscopy and thermogravimetric analysis all indicate that graphene oxides has been reduced. And the contact angle tests confirm the excellent hydrophobic performances of the synthesized carbon nanotube/reduced graphene oxide composite films. This one-step treatment represents a straightforward and high efficiency way for the reduction of carbon nanotubes/graphene oxides composites. [ABSTRACT FROM AUTHOR]

Flavivirus cDNA clones frequently demonstrate genetic instability in transformed bacteria, which hampers the construction and manipulation of cDNAs for infectious flaviviruses. In this study, we developed a stable, full-length cDNA clone, pJEHEN, of a GI JEV strain HEN0701 using a medium-copy-number pBR322 vector and propagating cDNA clones at room temperature. The virus vJEHEN recovered from the infectious clone was indistinguishable from the parent virus HEN0701 with respect to plaque morphology, growth kinetics, and virulence characteristics. A T-to-A silent mutation of nucleotide 24 of the NS2a gene was introduced into the infectious cDNA clone to eliminate frameshifting. The rescued mutant virus vJETA did not express NS1′ in infected cells and showed reduced growth and neurovirulence in mice. This convenient method for the construction and manipulation of infectious JEV cDNA clones may be of use in further studies to improve our understanding of the molecular mechanisms responsible for JEV replication and pathogenesis. [ABSTRACT FROM AUTHOR]

Improved understanding of the fractionation and geochemical characteristic of rare earth elements (REEs) from steel plant emissions is important due to the unclear atmospheric signature of these elements and their adverse impact on human health and the environment. In this study, ambient particulate matter of different sizes was collected from one site in an integrated iron and steelmaking industrial zone (HG) and one urban background site with no direct industrial emissions (ZWY) during a 1-year sampling campaign in China. The total concentrations of REEs for TSP, PM and PM were 27.248, 14.989, 3.542 ng/m in HG and 6.326, 5.274, 1.731 ng/m, respectively, in ZWY, which revealed the local influence of the steelmaking activities to the air quality. With respect to ZWY, the REEs in HG site are obviously fractionated in the coarser fraction, and LREEs account for more than 80 % of the total REE burden in all of the samples. Additionally, the REEs in HG and ZWY show a homogeneous trend with successively increased LREE/HREE ratios from the coarse particles to the fine particles. In our samples, La, Ce, Nd, and Sm are the most enriched rare earth elements, especially in the HG site. Moreover, ternary diagrams of LaCeSm indicate that the REEs in HG are potentially contributed by steelworks, carrier vehicles, coal combustion, and road dust re-suspension. [ABSTRACT FROM AUTHOR]

The Ras-like GTPases RalA and RalB are important drivers of tumour growth and metastasis. Chemicals that block Ral function would be valuable as research tools and for cancer therapeutics. Here we used protein structure analysis and virtual screening to identify drug-like molecules that bind to a site on the GDP-bound form of Ral. The compounds RBC6, RBC8 and RBC10 inhibited the binding of Ral to its effector RALBP1, as well as inhibiting Ral-mediated cell spreading of murine embryonic fibroblasts and anchorage-independent growth of human cancer cell lines. The binding of the RBC8 derivative BQU57 to RalB was confirmed by isothermal titration calorimetry, surface plasmon resonance and 1H-15N transverse relaxation-optimized spectroscopy (TROSY) NMR spectroscopy. RBC8 and BQU57 show selectivity for Ral relative to the GTPases Ras and RhoA and inhibit tumour xenograft growth to a similar extent to the depletion of Ral using RNA interference. Our results show the utility of structure-based discovery for the development of therapeutics for Ral-dependent cancers. [ABSTRACT FROM AUTHOR]

The factors that determine the transcription-regulating sequence (TRS) activity of porcine reproductive and respiratory syndrome virus (PRRSV) remain largely unclear. In this study, the effect of mutagenesis of conserved C nucleotides at positions 5 and 6 in the leader TRS (TRS-L) and/or canonical body TRS7 (TRS-B) on the synthesis of subgenomic (sg) mRNA and virus infectivity was investigated in the context of a type 2 PRRSV infectious cDNA clone. The results showed that a double C mutation in the leader TRS completely abolished sg mRNAs synthesis and virus infectivity, but a single C mutation did not. A single C or double C mutation in TRS-B or/and TRS-B impaired or abolished the corresponding sg mRNA synthesis. Introduction of identical mutations in the leader and body TRSs partially restored sg mRNA7.1 and/or sg mRNA7.2 transcription, indicating that the base-pairing interaction between sense TRS-L and cTRS-B is a crucial factor influencing sg mRNA synthesis. Analysis of the mRNA leader-body junctions of mutants provided evidence for a mechanism of discontinuous minus-strand transcription. This study also showed that mutational inactivation of TRS-B or TRS-B did not affect the production of infectious progeny virus, and the sg mRNA formed from each of them could express N protein. However, TRS-B plays more important roles than TRS-B in maintaining the growth characteristic of type 2 PRRSV. These results provide more insight into the molecular mechanism of genome expression and subgenomic mRNA transcription of PRRSV. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) can impact viral infections by binding to sequences with partial complementarity on viral RNA transcripts, usually resulting in the repression of virus replication. In the present study, we identified a potential binding site for miR-130 in the 5′ untranslated region (bps 155-162) of the porcine reproductive and respiratory syndrome virus (PRRSV) genome. We found that the delivery of multiple miR-130 family mimics, especially miR-130b, resulted in inhibition of PRRSV replication in vitro. miR-130 was effective in inhibiting the replication of multiple type 2 PRRSV strains, but not against vSHE, a classical type 1 strain. miR-130 over-expression did not induce IFN-α or TNF-α expression in either uninfected or PRRSV-infected porcine alveolar macrophages. Results from luciferase reporter assays indicated that miR-130 directly targeted the PRRSV 5′ UTR. Intranasal inoculation of piglets with miR-130b exhibited antiviral activity in vivo and partially protected piglets from an otherwise lethal challenge with HP-PRRSV strain vJX143. Overall, these results demonstrate the importance of the miR-130 family in modulating PRRSV replication and also provide a scientific basis for using cellular miRNAs in anti-PRRSV therapies. [ABSTRACT FROM AUTHOR]