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Abstract Ultralight dark photons constitute a well-motivated candidate for dark matter. A coherent electromagnetic wave is expected to be induced by dark photons when coupled with Standard-Model photons through kinetic mixing mechanism, and should be spatially correlated within the de Broglie wavelength of dark photons. Here we report the first search for correlated dark-photon signals using a long-baseline network of 15 atomic magnetometers, which are situated in two separated meter-scale shield rooms with a distance of about 1700 km. Both the network’s multiple sensors and the shields large size significantly enhance the expected dark-photon electromagnetic signals, and long-baseline measurements confidently reduce many local noise sources. Using this network, we constrain the kinetic mixing coefficient of dark photon dark matter over the mass range 4.1 feV-2.1 peV, which represents the most stringent constraints derived from any terrestrial experiments operating over the aforementioned mass range. Our prospect indicates that future data releases may go beyond the astrophysical constraints from the cosmic microwave background and the plasma heating.

Abstract Since the first outbreak in December 2019, SARS-CoV-2 has been constantly evolving and five variants have been classified as Variant of Concern (VOC) by the World Health Organization (WHO). These VOCs were found to enhance transmission and/or decrease neutralization capabilities of monoclonal antibodies and vaccine-induced antibodies. Here, we successfully designed and produced a recombinant COVID-19 vaccine in CHO cells at a high yield. The vaccine antigen contains four hot spot substitutions, K417N, E484K, N501Y and D614G, based on a prefusion-stabilized spike trimer of SARS-CoV-2 (S-6P) and formulated with an Alum/CpG 7909 dual adjuvant system. Results of immunogenicity studies showed that the variant vaccine elicited robust cross-neutralizing antibody responses against SARS-CoV-2 prototype (Wuhan) strain and all 5 VOCs. It further, stimulated a TH1 (T Helper type 1) cytokine profile and substantial CD4+ T cell responses in BALB/c mice and rhesus macaques were recorded. Protective efficacy of the vaccine candidate was evaluated in hamster and rhesus macaque models of SARS-CoV-2. In Golden Syrian hamsters challenged with Beta or Delta strains, the vaccine candidate reduced the viral loads in nasal turbinates and lung tissues, accompanied by significant weight gain and relieved inflammation in the lungs. In rhesus macaque challenged with prototype SARS-CoV-2, the vaccine candidate decreased viral shedding in throat, anal, blood swabs over time, reduced viral loads of bronchus and lung tissue, and effectively relieved the lung pathological inflammatory response. Together, our data demonstrated the broadly neutralizing activity and efficacy of the variant vaccine against both prototype and current VOCs of SARS-CoV-2, justifying further clinical development.

As a polycrystalline polymer, isotactic polybutene-1 (iPB-1) will form different crystalline structures when it crystallizes under different conditions. In this work, we found a simple method to manipulate the cell structure of iPB-1 foams by controlling the annealing time of crystalline form II at room temperature and employing supercritical CO2 foaming. As the content of crystalline form II increases, the storage modulus (G′) and complex viscosity (|η * |) increase, and the solubility of CO2 in iPB-1 increases. Crystalline form II has a wider foaming temperature window compared to crystalline form I and exhibits a more uniform cell structure at temperatures between 95 °C and 125 °C. The average cell diameters of crystalline form II and I are 33.9 µm and 11.2 µm at 115 °C and 15 MPa CO2, respectively. A small amount of crystalline form I acts as a heterogeneous nucleation agent during the foaming process, resulting in the formation of a “petal-like” cell structure. During the foaming saturation process, the melted portion of iPB-1 with unstable crystalline form II transforms into crystalline form I′ under high-pressure CO2, while the unmelted portion transforms into crystalline form I. As the pressure increases, the cell structure of iPB-1 undergoes a transition from “petal-like” to bimodal cell structure, ultimately achieving a more uniform structure. Moreover, increasing foaming pressure can also change the cell structure of the foamed material from closed-cell to open-cell. The occurrence of bimodal melting peaks in the foamed samples is beneficial for the adhesion of beads during the molding process.

A series of microcellular polypropylene (PP) with different bubble size and expansion ratio were prepared by supercritical CO2 moulding compression foaming, and their compressive, flexural and tensile properties were measured. A comprehensive calculation model for the mechanical properties of polymer foam based on tetradecahedron structure was further established, and the error between the simulation results and the experimental results is less than 25%. Based on the model, the contributions of the elastic stress of polymer matrix and counter-acting force of gas to the elastic modulus were quantitatively analyzed for the first time. The results show that the smaller bubble size can improve the compressive elastic modulus and flexural elastic modulus but has little effect on the tensile elastic modulus. At the same time, the counter-acting force of gas has a positive effect on the compressive elastic modulus, but has a weakening effect on the tensile elastic modulus, and has almost no effect on the flexural elastic modulus. Finally, the generality of the above model is verified by the prediction for elastic modulus of different polymer foams.

Abstract Background Cervical cancer (CC) endangers women’s health in the world range. Accumulating studies have revealed the crucial regulatory role of long non-coding RNAs (lncRNAs) in multiple malignancies, including CC. Our study aimed to explore the role of lncRNA double homeobox A pseudogene 8 (DUXAP8) in cervical carcinogenesis. Methods Gene expressions in CC were assessed by RT-qPCR. Function experiments and tube formation assays were performed to evaluate the role of DUXAP8 in CC cells. Subcellular fractionation and FISH assays were conducted to determine the subcellular location of DUXAP8. Luciferase reporter, RNA pull down and RIP assays were conducted to investigate the mechanism of DUXAP8. Results DUXAP8 was notably upregulated in CC cells. Downregulation of DUXAP8 repressed cell malignant behaviors and angiogenesis in CC. Mechanically, DUXAP8 boosted the expression of reticulocalbin-2 (RCN2) through relieving the binding of miR-1297 to RCN2 3’-UTR. Moreover, miR-1297 inhibition and RCN2 overexpression could counteract the inhibitory effects of DUXAP8 knockdown on the malignant phenotypes of CC cells. Besides, enhanced RCN2 expression restored the tumor growth in vivo that was inhibited by DUXAP8 repression. Conclusions DUXAP8 promotes malignant behaviors in CC cells via regulating miR-1297/RCN2 axis. Graphical Abstract

Abstract In principle, polymerization tends to produce amorphous or poorly crystalline materials. Efficiently producing high-quality single crystals by polymerization in solvent remains as an unsolved issue in chemistry, especially for covalent organic frameworks (COFs) with highly complex structures. To produce μm-sized single crystals, the growth time is prolonged to >15 days, far away from the requirements in practical applications. Here, we find supercritical CO2 (sc-CO2) accelerates single-crystal polymerization by 10,000,000 folds, and produces two-dimensional (2D) COF single crystals with size up to 0.2 mm within 2~5 min. Although it is the fastest single-crystal polymerization, the growth in sc-CO2 leads to not only the largest crystal size of 2D COFs, but also higher quality with improved photoconductivity performance. This work overcomes traditional concept on low efficiency of single-crystal polymerization, and holds great promise for future applications owing to its efficiency, industrial compatibility, environmental friendliness and universality for different crystalline structures and linkage bonds.

Abstract The Cooling Storage Ring (CSR) External-target Experiment (CEE) will be the first large-scale nuclear physics experimental device at the CSR of the Heavy-Ion Research Facility in Lanzhou (HIRFL) in China. A new T0 detector has been proposed to measure the multiplicity, angular distribution and timing information of charged particles produced in heavy-ion collisions at the target region. Multi-gap resistive plate chamber (MRPC) technology was chosen as part of the construction of the T0 detector, which provides precision event collision times (T0) and collision geometry information. The prototype was tested with hadron and heavy-ion beams to study its performance. By comparing the experimental results with a Monte Carlo simulation, the time resolution of the MRPCs are found to be better than $$\sim 50$$ ∼50 ps. The timing performance of the T0 detector, including both detector and readout electronics, is found to fulfil the requirements of the CEE.

Effect of CO2-philic additive additives PDMS and co-blowing agent alcohol on dynamic bubble growth behavior of supercritical CO2 assisted polymer foaming process, was investigated by using a visual observation system combined with numeric model. The addition of PDMS in PS accelerates the bubble nucleation and growth rate, and the bubble growth rate decreases with the increase of PDMS molecular weight. The bubble growth of polymer is mainly determined by the effect of PDMS on the solubility and diffusion of CO2, and the bubble growth model has a good agreement with the experimental values. When using alcohols as co-blowing agents, 1-butanol and 1-hexanol accelerates the bubble growth rate owing to the strong plasticizing effect on PS, resulting that the predicted bubble growth rate and bubble diameter has a deviation with the experimental data. Alcohol significantly decreased the diffusion coefficient of blowing agent, the bubble growth is controlled collectively by the dissolution and diffusion of blowing agent and the viscosity of polymer matrix after plasticizing.

Disposal of soil from foundation excavation in the construction industry has been recognised as a critical challenge for environmental protection. This study investigates the feasibility of incorporating dewatered extracted soil (DES) in concrete blocks manufactured with ordinary Portland cement (OPC) or alkali-activated slag (AAS). The physical and engineering properties, including bulk density, water absorption, compressive strength and flexural strength, of the concrete blocks with different contents of DES were investigated. Scanning electron microscope (SEM) analysis was also conducted to investigate the microstructure of the blocks. The results indicate that replacing sand by DES can enhance the physical and mechanical properties of the concrete blocks. The optimal replacement ratios are 30% for the OPC concrete blocks (OPCCB) and 20% for the AAS concrete blocks (AASCB). At the optimal replacement ratios, the densities of OPCCB and AASCB are 10.5% and 19.6% higher than those without DES, respectively, while the water absorption ratios are 38.0% and 48.7% lower than those without DES, respectively. Consequently, the 28-day compressive and flexural strengths for both blocks were increased by over 100%. The SEM photographs indicate that the improvements are attributed to the densification of the structure. However, further increasing the incorporation ratio of DES increases the surface area of total aggregates and requires more OPC or AAS to bind them, which consequently weakens the properties of concrete blocks. Besides, the strength of concrete blocks with AAS is around 2 times that with the same amount of OPC, indicating that AAS is more effective in improving the strength of concrete blocks. Moreover, a cradle-to-gate life cycle assessment (LCA) was performed to analyse the energy consumption and embodied carbon of the concrete blocks. The results indicate that AASCBs exhibits superior environmental sustainability over both conventional fired clay bricks and OPCCBs. Results in this study can help promote the application of DES in producing green concrete blocks.

Abstract In this paper, the implicit midpoint method is presented for solving Riesz tempered fractional diffusion equation with a nonlinear source term, where the tempered fractional partial derivatives are evaluated by the modified second-order Lubich tempered difference operator. Stability and convergence analyses of the numerical method are given. The numerical experiments demonstrate that the proposed method is effective.

MaZiRenWan (MZRW, also known as Hemp Seed Pill) is a Chinese Herbal Medicine which has been demonstrated to safely and effectively alleviate functional constipation (FC) in a randomized, placebo-controlled clinical study with 120 subjects. However, the underlying pharmacological actions of MZRW for FC, are still largely unknown. We systematically analyzed the bioactive compounds of MZRW and mechanism-of-action biological targets through a novel approach called “focused network pharmacology.” Among the 97 compounds identified by UPLC-QTOF-MS/MS in MZRW extract, 34 were found in rat plasma, while 10 were found in rat feces. Hierarchical clustering analysis suggest that these compounds can be classified into component groups, in which compounds are highly similar to each other and most of them are from the same herb. Emodin, amygdalin, albiflorin, honokiol, and naringin were selected as representative compounds of corresponding component groups. All of them were shown to induce spontaneous contractions of rat colonic smooth muscle in vitro. Network analysis revealed that biological targets in acetylcholine-, estrogen-, prostaglandin-, cannabinoid-, and purine signaling pathways are able to explain the prokinetic effects of representative compounds and corresponding component groups. In conclusion, MZRW active components enhance colonic motility, possibly by acting on multiple targets and pathways.

To solve the poor cellular morphology of linear iPB-1 during supercritical CO2 foaming, the modification and the special crystalline transition behavior of iPB-1 were used to improve its foaming performance. Based on free radical polymerization, long-chain branching iPB-1 is achieved. Long-chain branching structures not only reduce crystallinity of iPB-1, but also increase the crystallization temperature. Long-chain branching structures can accelerate the crystalline transformation rate of iPB-1. After annealing at room temperature for 24 h, the crystalline transformation of the raw iPB-1 material is completed by 14%, while long-chain branching iPB-1 reaches 33%. The crystalline transformation of the modified iPB-1 is completed by 85% after annealing for 48 h. Compared with the raw iPB-1 material with crystalline form I, the introduction of long-chain branching structures is favorable for broadening the foaming temperature interval from 10 to 20(C, while the foaming temperature interval of the long-chain branching iPB-1 with crystalline form II increases to 25°C. The iPB-1 with high content of crystalline form I and long-chain branching structures are conductive to the formation of uniform cells. This will broaden the application of iPB-1 foam in automotive interiors, packaging, and transportation fields. [ABSTRACT FROM AUTHOR]