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Abstract Metasurfaces have shown unparalleled controllability of electromagnetic (EM) waves. However, most of the metasurfaces need external spatial feeding sources, which renders practical implementation quite challenging. Here, a low‐profile programmable metasurface with 0.05λ0 thickness driven by guided waves is proposed to achieve dynamic control of both amplitude and phase simultaneously. The metasurface is fed by a guided wave traveling in a substrate‐integrated waveguide, avoiding external spatial sources and complex power divider networks. By manipulating the state of the p‐i‐n diodes embedded in each meta‐atom, the proposed metasurface enables 1‐bit amplitude switching between radiating and nonradiating states, as well as a 1‐bit phase switching between 0° and 180°. As a proof of concept, two advanced functionalities, namely, low sidelobe‐level beam scanning and Airy beam generation, are experimentally demonstrated with a single platform operating in the far‐ and near‐field respectively. Such complex‐amplitude, programmable, and low‐profile metasurfaces can overcome integration limitations of traditional metasurfaces, and open up new avenues for more accurate and advanced EM wave control within an unprecedented degree of freedom.

The materials supply for sea islands is the basis for ensuring survival needs of persons on sea islands. Considering factors such as transportation cost, storage cost, recycling demand and transportation capacity, it is a vehicle path planning problem with time window and capacity limit to use many transportation tools to supply materials for sea islands within a time cycle. The intelligent algorithm provides a preferable solution to solve this complex irregular optimization problem. The paper establishes a mathematical model of mission planning of materials supply for sea islands, explores the solving process of genetic algorithm, and uses an example to calculate it. The optimization result shows that the scheme can save transportation costs and storage costs, and also meet the need of materials supply cycle, which can provide a reference for scientific mission planning of materials supply for sea islands.

Facing the intricate challenges of English instruction in higher vocational colleges, this research innovatively employs online resources to elevate educational quality and learner efficiency. It critiques the ineffectiveness of “one-size-fits-all” educational models and proposes a cutting-edge personalized recommendation system. This system adeptly curates learning materials to align with individual students’ learning patterns and competencies. By pioneering the TDINA and CUPMF models, and synergizing them with convolutional neural network (CNN) technology, our study dives deep into the educational content, ensuring precise resource recommendations. The system’s prowess was demonstrated through the successful recommendation of 815 resources, identifying strengths in electronic wall charts and courseware, alongside areas for enhancement in microclass scripts and recordings. A specialized experiment in personalized exercise recommendations further underscored the system’s efficacy, accurately tailoring the exercise level and difficulty to students’ learning capacities. Significantly, the CUPMF model emerged as a robust tool in refining the accuracy of these personalized recommendations, heralding a new era of bespoke educational experiences for students.

In this study, zein-based gluten-free model dough (Z dough) was prepared with zein, corn starch, and wormwood gum. Based on the flour quality test, the kneading torque, water composition and protein distribution of the zein simulated dough with different lactic acid content were compared when finish dough (torque up to 1.1 Nm; set as ZS dough) and kneading for 12 minutes (set as ZL dough) conditions. The optimal amount of lactic acid added to kneadable dough was explored, and the physical and chemical properties of zein in dough with different lactic acid content were discussed under the action of kneading for a certain period of time, which could and provide reference for the preparation of related cereal products. Studies have shown that adding a small amount of lactic acid could promote zein to build a protein network in the dough, but long-term kneading would lead to decreasing the strength of the acidified dough, destroying the continuity of the zein network in the dough, reducing the level of zein wrapping on starch granules and weak bonding in the dough. The proportion of water decreased and the proportion of free water increased. The surface hydrophobicity increased and the relative molecular weight decreased, when the deamidation reaction of zein occurred. The analysis showed that the dough gradually weakened after a long time of kneading, because the kneading effect would expand the effect of lactic acid on zein in the dough, which would increase the hydrophobicity of the protein surface and fragment the protein, and lead to a decrease in the coherence of the zein network.

Both community variation and phosphorus (P) fractions have been extensively studied in aquatic ecosystems, but how P fractions affect the mechanism underlying microbial beta diversity remains elusive, especially in sediment cores. Here, we obtained two sediment cores to examine bacterial and archaeal beta diversity from mesotrophic lakes Hongfeng Lake and Aha Lake, having historically experienced severe eutrophication. Utilizing the Baselga’s framework, we partitioned bacterial and archaeal total beta diversity into two components: species turnover and nestedness, and then examined their sediment-depth patterns and the effects of P fractions on them. We found that total beta diversity, species turnover or nestedness consistently increased with deeper sediment layers regarding bacteria and archaea. Notably, there were parallel patterns between bacteria and archaea for total beta diversity and species turnover, which is largely underlain by equivalent processes such as environmental selection. For both microbial taxa, total beta diversity and species turnover were primarily constrained by metal oxide-bound inorganic P (NaOH-Pi) and sediment total phosphorus (STP) in Hongfeng Lake, while largely affected by reductant-soluble total P or calcium-bound inorganic P in Aha Lake. Moreover, NaOH-Pi and STP could influence bacterial total beta diversity by driving species nestedness in Hongfeng Lake. The joint effects of organic P (Po), inorganic P (Pi) and total P fractions indicated that P fractions are important to bacterial and archaeal beta diversity. Compared to Po fractions, Pi fractions had greater pure effects on bacterial beta diversity. Intriguingly, for total beta diversity and species turnover, archaea rather than bacteria are well-explained by Po fractions in both lakes, implying that the archaeal community may be involved in Po mineralization. Overall, our study reveals the importance of P fractions to the mechanism underlying bacterial and archaeal beta diversity in sediments, and provides theoretical underpinnings for controlling P sources in biodiversity conservation.

Objective To analyze the status of proficiency testing samples in the field of laboratory animal testing, and to evaluate the role of the testing samples in the laboratory animal laboratory proficiency testing program.MethodsA retrospective study was conducted to compare the 30 proficiency testing plans and reports in the field of laboratory animal organized by National Institute for Food and Drug Control (NIFDC) from 2013 to 2022. The type, quantity, preparation method, homogeneity and stability of the proficiency testing samples, as well as the satisfaction of the participating units to the samples were analyzed. Then, the supply of new samples, the addition of quantitative projects, the improvement of stability research and the attention to customer needs were discussed.ResultsThe 30 proficiency testing programs included 10 items in the direction of bacteria, 10 items in the direction of virus and 10 items in the direction of genetics in the field of experimental animals. A total of 80 non-nucleic acid samples (including serums, feces, tracheal flushing fluid and proteins) and 4 nucleic acid samples were provided, all of which were qualitative samples. Compared with nucleic acid samples, non-nucleic acid samples always required large numbers of animals for sample preparation. The pass rate of homogeneity verification of the sample was 100%, but there is no quantitative study at present. Stability verification can be conducted for the short-term storage, transportation, freeze-thaw, different concentrations and terminal stability of different samples, but it lacks long-term stability verification.ConclusionIn the past ten years, the proficiency testing samples have basically met the basic requirements of the proficiency testing plan of laboratory animal testing area. However, the provision of nucleic acid samples should be reasonably increased; quantitative research samples and projects should be added; the influence of proficiency testing in the field of laboratory animal testing should be continuously expanded and maintain high-quality services.

ObjectiveTo test the single nucleotide polymorphism (SNP) detection technology level of mice genetic quality control in laboratories, promote the application of nucleic acid samples and SNP detection technology by implementing a nationwide proficiency testing program.MethodsIn 2022, National Institutes for Food and Drug Control implemented domestic laboratory proficiency testing named“NIFDC-PT-365 Laboratory Proficiency Testing Program of SNP Marker Detection Ablity in Laboratory Mice DNA Samples”. According to the requirements of the program, each participating laboratory received 2 blind samples of DNA from BALB/c mice and C57BL/6 mice with random numbers, standard operation procedure and 2 pairs of primers for rs3023177 and rs3023382 SNP loci. The participants should submit the results and original records before the deadline. If the mutation site amplification and sequencing results were consistent with the preseted results, it was considered as satisfactory; otherwise, it was considered as unsatisfactory. Meanwhile, PCR amplification system, sequencing direction and alignment methods of participating laboratories were compared to analyze as the relevant factors which may affect the SNP detection results of nucleic acid standard samples.ResultsThe results of 10 participating laboratories were consistent with the preset. They all obtained satisfactory results. Differences in amplification volume (20 μL, 25 μL, 30 μL), Taq enzyme system (single component and PCR MIX), sequencing company, sequencing direction and alignment software had no influence on the accuracy of the results.ConclusionThe participating laboratories have high detection ability in SNP detection method of mice nucleic acid samples. SNP detection technology is simple and feasible in mouse genetic quality control and is worth popularizing.

Transcription factors, human E26 transcription factor 1 (Ets1) and specific protein 1 (Sp1), are known to induce gene expression in tumorigenicity. High Ets1 expression is often associated with colorectal tumorigenesis. In this study, we discover that metastasis and clone formation in SW480 cells mainly depend on the direct interaction between Ets1 and Sp1 instead of high Ets1 expression. The interaction domains are further addressed to be the segment at Sp1(626-708) and the segment at Ets1(244-331). In addition, the phosphorylation inhibition of Ets1 at Tyr283 by either downregulation of Src kinase or Src family inhibitor treatment decreases the interaction between Sp1 and Ets1 and suppresses SW480 migration. Either administration or overexpression of the peptides harboring the interaction segment strongly inhibits the colony formation and migration of SW480 cells. Our findings suggest that the interaction between Ets1 and Sp1 rather than Ets1 alone promotes transformation in SW480 cells and provide new insight into the Ets1 and Sp1 interaction as an antitumour target in SW480 cells.

In this work, a low-cost all-metal metamaterial near-field lens based on laser cutting technology is proposed. A novel spiral-slot structure is proposed to achieve miniaturized unit cells with an adjustable 360-degree phase shift at a length smaller than 0.2 times the operating wavelength. Since the unit is entirely constructed of stainless steel, it is resistant to high temperatures and high pressures compared to existing results. Moreover, a four-layer structure is used to increase the transmission coefficient. The final L-band near-field lens is constructed of 20 × 20 units. Simulation and measured results show that the half-power beamwidth of the focus is less than 211 mm from 1.52 GHz to 1.68 GHz at the focal spot observation plane of 500 mm from the lens. Since numerically controlled machine tools and three-dimensional printing are prohibitively expensive for machining large metal components, a low-cost all-metallic lens was manufactured using laser cutting technology. The measured results are in agreement with the simulation results.

Health risks caused by heavy metal (HM) exposure in road dust has attracted extensive attention, but few studies have focused on the health risks of residents living in small- and medium-sized cities with rapid industrialization and urbanization. Thus, 140 road dust samples were collected across Anyang, a typical fourth-tier industrial city in central China, which were analysed for 10 different HMs (Mn, Zn, Pb, V, Cr, As, Cd, Ni, Cu and Co). Monte Carlo simulation and bioaccessibility were used to quantify the health risks of heavy metals comprehensively in road dust. Results revealed a remarkable accumulation of Mn, Zn, Pb, Cd and Cu. According to the Geo-accumulation index and potential ecological risk index, Cd was priority control pollutant. Moreover, 55.0% of the road dust samples reached heavily polluted level, and 52.86% of the samples were at high ecological risk levels. These results illustrated that HM contamination was serious and universal in the road dust of Anyang. The occurrences of HMs were allocated to traffic emissions, natural sources, industrial activities and agricultural activities with contribution rates of 35.4%, 6.0%, 41.6% and 17.0%, respectively. Except for Zn in the gastric phase, all other HMs had relatively low bioaccessibilities in the gastrointestinal system, usually less than 20%. The bioaccessibilities of most HMs were higher in the gastric phase, except for Cr, Ni and Cu, which remained higher in the intestinal phase. The non-carcinogenic risk and carcinogenic risk were remarkably reduced when considering the HM bioaccessibilities in the gastrointestinal system, especially for adults. The outcomes of this paper are valuable for understanding HM contamination in road dust and highlight the importance of risk assessment for populations living in the fourth- and fifth-tier cities.