Biodegradable microplastics pose greater risks than conventional microplastics to soil properties, microbial community and plant growth, especially under flooded conditions.

Biodegradable plastics (bio-plastics) are often viewed as viable option for mitigating plastic pollution. Nevertheless, the information regarding the potential risks of microplastics (MPs) released from bio-plastics in soil, particularly in flooded soils, is lacking. Here, our objective was to investigate the effect of polylactic acid MPs (PLA-MPs) and polyethylene MPs (PE-MPs) on soil properties, microbial community and plant growth under both non-flooded and flooded conditions. Our results demonstrated that PLA-MPs dramatically increased soil labile carbon (C) content and altered its composition and chemodiversity. The enrichment of labile C stimulated microbial N immobilization, resulting in a depletion of soil mineral nitrogen (N). This specialized environment created by PLA-MPs further filtered out specific microbial species, resulting in a low diversity and simplified microbial community. PLA-MPs caused an increase in denitrifiers (Noviherbaspirillum and Clostridium sensu stricto) and a decrease in nitrifiers (Nitrospira, MND1, and Ellin6067), potentially exacerbating the mineral N deficiency. The mineral N deficit caused by PLA-MPs inhibited wheatgrass growth. Conversely, PE-MPs had less effect on soil ecosystems, including soil properties, microbial community and wheatgrass growth. Overall, our study emphasizes that PLA-MPs cause more adverse effect on the ecosystem than PE-MPs in the short term, and that flooded conditions exacerbate and prolong these adverse effects. These results offer valuable insights for evaluating the potential threats of bio-MPs in both uplands and wetlands.

Case report: Rapidly progressive desmoid tumor after surgery for esophagogastric junction cancer and slowly progressive primary desmoid tumor: a report of two cases and literature review.

Background: Desmoid tumor (DT) is a rare locally aggressive but non-metastatic mesenchymal soft tissue neoplasm that predominantly occurs in the abdominal wall, abdominal cavity, and extremities. Its occurrence in the mesentery is relatively uncommon. Case reports: This article reports two cases of desmoid tumor treated at the Department of Gastrointestinal Surgery, Weifang People's Hospital. The first case was a 59-year-old male patient who had previously undergone surgery for esophagogastric junction cancer. Postoperatively, he developed an intra-abdominal mass that rapidly increased in size within three months. The second case was a 60-year-old male patient who incidentally discovered a mass in the left lower abdomen. Both patients underwent surgical treatment, and the postoperative pathological diagnosis was mesenteric desmoid tumor. Conclusion: The treatment of desmoid tumor remains challenging. Simple surgical resection often yields unsatisfactory outcomes, and the efficacy of adjuvant radiotherapy and chemotherapy is also limited. Further research and clinical practice are necessary to improve diagnostic and therapeutic strategies, aiming to enhance patient survival and quality of life.

Prediction of intrinsic room-temperature ferromagnetism in two-dimensional CrInX2 (X = S, Se, Te) monolayers.

Herein, using density functional theory, novel two-dimensional (2D) CrInX2 (X = S, Se, Te) structures are predicted to be practical ferromagnetic (FM) semiconductors. Phonon vibrations and molecular dynamics simulations verified their structural and thermodynamic stability. Sizable fully spin-polarized band gaps of 1.03 and 0.69 eV are found for CrInS2 and CrInSe2, while CrInTe2 exhibits half-metallic band nature (at 0 K with a perfect lattice). The high magnetic anisotropy energies are responsible for their long-range spin polarization. The Curie temperatures (Tc) are estimated to be 347, 397 and 447 K for CrInS2, CrInSe2 and CrInTe2, respectively, all well above the room-temperature. The high Tc originates from unusual FM direct exchange, the efficient super-exchange coupling between neighboring Cr eg-orbitals with zero virtual exchange gaps and the presence of dual Cr-X-Cr super-exchange channels. Our systematic study of the CrInX2 monolayer suggests that it could be a promising material for spintronics applications.

Photosynthesis promotion mechanisms of artificial humic acid depend on plant types: A hydroponic study on C3 and C4 plants.

It is feasible to improve plant photosynthesis to address the global climate goals of carbon neutrality. The application of artificial humic acid (AHA) is a promising approach to promote plant photosynthesis, however, the associated mechanisms for C3 and C4 plants are still unclear. In this study, the real-time chlorophyll synthesis and microscopic physiological changes in plant leave cells with the application of AHA were first revealed using the real-time chlorophyll fluorescence parameters and Non-invasive Micro-test Technique. The transcriptomics suggested that the AHA application up-regulated the genes in photosynthesis, especially related to chlorophyll synthesis and light energy capture, in maize and the genes in photosynthetic vitality and carbohydrate metabolic process in lettuce. Structural equation model suggested that the photodegradable substances and growth hormones in AHA directly contributes to photosynthesis of C4 plants (0.37). AHA indirectly promotes the photosynthesis in the C4 plants by upregulating functional genes (e.g., Mg-CHLI and Chlorophyllase) involved in light capture and transformation (0.96). In contrast, AHA mainly indirectly promotes C3 plants photosynthesis by increasing chlorophyll synthesis, and the Rubisco activity and the ZmRbcS expression in the dark reaction of lettuce (0.55). In addition, Mg2+ transfer and flux in C3 plant leaves was significantly improved by AHA, indirectly contributes to plant photosynthesis (0.24). Finally, the AHA increased the net photosynthetic rate of maize by 46.50 % and that of lettuce by 88.00 %. Application of the nutrients- and hormone-rich AHA improves plant growth and photosynthesis even better than traditional Hoagland solution. The revelation of the different photosynthetic promotion mechanisms on C3 and C4 plant in this work guides the synthesis and efficient application of AHA in green agriculture and will propose the development of AHA technology to against climate change resulting from CO2 emissions in near future.

Construction and Performance of Superhydrophobic Surfaces for Rusted Iron Artifacts.

Ancient iron artifacts need to be protected with a rust layer, often stabilized by tannic acid corrosion inhibition. In humid environments, water vapor could slowly penetrate and trigger galvanic corrosion of metal artefacts. Sealing treatments are generally applied to the artefact surface to isolate water and enhance its corrosion resistance. Superhydrophobic modifications could effectively block the penetration of moisture into the interior of the artefact and provide a nice water barrier. Stearic acid with tannic acid inhibition treatment creates a superhydrophobic protective layer on the surface of rusted iron artifacts and enhances corrosion resistance effectively. Various scientific analyses and testing methods are used in this paper to evaluate the corrosion resistance of rusted surfaces after superhydrophobic modification and investigate the reaction mechanisms. The results indicate that the contact angle of the rusted surface after corrosion inhibition by tannic acid and modified by stearic acid is increased to 152.2°, which means the superhydrophobic protective layer has been successfully constructed. The C/Fe ratio of the rusted surface is increased from 0.21 to 2.10, and the characteristic diffraction peaks of O1s and Fe 2p3/2 shift toward higher binding energy. Stearic acid is combined with the corrosion product layer by chemical bonding. Chelation between rust products, tannic acid, and steric acid is effective, and the chelate is chemically stable. The superhydrophobic surface forms a lamellar wax-like layer as an air barrier to isolate liquid water, resulting in a significant decrease in corrosion current and an increase in Warburg impedance to 217.9 times the original state, with a protection efficiency of 88.3%. Tannic acid corrosion inhibition and stearic acid superhydrophobic modification have an excellent synergistic protective effect on improving the corrosion resistance of iron artifacts, resulting in better corrosion resistance of iron artifact materials. The research provides new ideas and references for the protection of ancient iron artifacts sealing.

Rust Conversion of Proanthocyanidins to Archaeological Steel: A Case Study of Lingzhao Xuan in the Forbidden City.

This work was focused on the rust conversion of proanthocyanidins (PC) for goethite (α-FeOOH), akaganeite (ß-FeOOH) and lepidocrocite (γ-FeOOH), trying to show the potential of PC as an eco-friendly corrosion inhibitor and rust converter for archaeological steel conservation. The experiment used a rusted steel screw from Lingzhao Xuan of the Forbidden City in the Qing Dynasty and three kinds of pure iron oxyhydroxides as research samples. By means of micro-Raman, FTIR, XRD, XPS, SEM and EIS, PC had the ability to chemically react with iron oxyhydroxides in the rust, forming amorphous PC-FeOOH with a marked signal about 1384 cm-1 as phenolic-Fe in infrared properties. The original relatively stable iron oxides were not induced to phase transformation and still remained. The converted rust layer could be more stable in the corrosive medium and increased the corrosion potential more effectively. Both the rust layer resistance and the charge transfer resistance of the archaeological samples were improved by at least 3 times with 5.0 g/L of PC, which could reasonably stabilize the archaeological rust and hindered external corrosive penetration into the core. It was a mild protection material that showed satisfactory performance for archaeological steel cultural heritage and has a good application prospect.

Corrosion Layers on Archaeological Cast Iron from Nanhai I.

Archaeological iron objects were excavated from the Nanhai I ship from the Southern Song Dynasty that sunk in the South China Sea. Most of these artifacts were severely corroded and fragmented. In order to understand their current corrosion state and guide their restoration and protection, optical microscopy, scanning electron microscopy, micro-laser Raman spectroscopy, infrared spectroscopy and X-ray diffraction were all selected for analysis. It was clear that the archaeological iron material was hypereutectic white iron with a carbon content of about 4.3-6.69%, and had experienced low-melt undercooling. There were many internal cracks formed by general corrosion that extended to the iron core, which tended to make the material unstable. At the interface between the iron and rust, there was a black dense layer enriched with chlorine, and a loose yellow outer layer. The dense layer was mainly composed of magnetite, akaganeite and maghemite, while the rust of the loose layer was composed of lepidocrocite, goethite, feroxyhite, maghemite and hematite. The major phases of all corrosion products were akaganeite and lepidocrocite. Numerous holes and cracks in the rust layer exhibited no barrier ability to the outside electrolyte, hence the iron core formed many redox electrochemical sites for general corrosion with the rust. Meanwhile, the dense rust located close to the iron core was broken locally by an enriched chlorine layer that was extremely detrimental to the stability of the archaeological iron. Using electrochemical impedance spectroscopy, it could be determined that the rust layers had no protective effect on the internal iron core under conditions of simulated seawater, and these rust layers even accelerated the corrosion. A mechanism for the rust growth as a result of laboratory testing was proposed to explain the entire corrosion process. In view of the desalination preservation treatment that had been applied for ten years, it was not recommended to maintain a single desalination operation. The archaeological rusted iron of the Nanhai I ship that was excavated from the marine environment should be properly stabilized and protected using corrosion inhibition and rust transformation for iron oxyhydroxides, since the rust structure and the internal iron core retain well together.

Three Birds with One Stone: Preventive Protection of Paper Materials by ZnO-PHMB and UV-531 Composite Systems.

As the most frequently used archival materials for painting and recording, paper lays the groundwork for the development of prosperous human civilization. However, its susceptibility to three primary factors including external ultraviolet light, increased acidity, and biological pathogens in long-term storage shortens the longevity of paper. Therefore, the protection of paper-based cultural relics is extremely urgent. Inspired by the three adverse factors affecting the protection of cultural relics, we herein propose to combine the ultraviolet absorber 2-hydroxy-4-(octyloxy)benzophenone (UV-531) and alkaline zinc oxide (ZnO) nanoparticles innovatively into the antibacterial agent polyhexamethylene biguanidine hydrochloride (PHMB) to realize the strategy of three birds with one stone for relics protection. This study illustrates that the tensile strength and the folding endurance of different test papers are guaranteed by coating them with the composite reagents, and molds including Mucor, Trichoderma, and Aspergillus niger are effectually sterilized. In addition, a hand-painted Chinese ink-wash painting with beautiful flowers is chosen as the object for simulating cultural relics protection, and negligible color fading is observed in aging experiments. From the perspective of effectiveness, simplicity, and economy, this strategy sheds light on preservative protection of paper-based relics in long-term storage.

Second harmonic generation responses of KH2PO4: importance of K and breaking down of Kleinman symmetry.

The second harmonic generation (SHG) responses of the paraelectric and ferroelectric phases of KH2PO4 (KDP) were calculated by first-principles density functional theory (DFT) calculations, and the individual atom contributions to the SHG responses were analyzed by the atom response theory (ART). We show that the occurrence of static polarization does not enhance the SHG responses of the ferroelectric KDP, and that the Kleinman symmetry is reasonably well obeyed for the paraelectric phase, but not for the ferroelectric phase despite that the latter has a larger bandgap. This is caused most likely by the fact that the ferroelectric phase has lower-symmetry local structures than does the paraelectric phase. The contribution to the SHG response of an individual K+ ion is comparable to that of an individual O2- ion. The contributions of the O2- and K+ ions arise overwhelmingly from the polarizable parts of the electronic structure, namely, from the valence bands of the O-2p nonbonding states and from the conduction bands of the K-3d states.

Removal performance and water quality analysis of paper machine white water in a full-scale wastewater treatment plant.

Paper machine white water is generally characterized as a high concentration of suspended solids and organic matters. A combined physicochemical-biological and filtration process was used in the study for removing pollutants in the wastewater. The removal efficiency of the pollutant in physicochemical and biological process was evaluated, respectively. Furthermore, advanced technology was used to analyse the water quality before and after the process treatment. Experimental results showed that the removal efficiency of suspend solids (SS) of the system was above 99%, while the physicochemical treatment in the forepart of the system had achieved about 97%. The removal efficiency of chemical oxygen demand (COD) and colour had the similar trend after physicochemical treatment and were corresponding to the proportion of suspended and the near-colloidal organic matter in the wastewater. After biological treatment, the removal efficiency of COD and colour achieved were about 97% and 90%, respectively. Furthermore, molecular weight (MW) distribution analysis showed that after treatment low MW molecules (<5 kDa) increased. Three-dimensional excitation-emission matrix fluorescence analysis showed that most humic-like substances were effectively removed during the treatment. The analyses of gas chromatography/mass spectrometry showed that the composition of organic matter in the wastewater was not complicated. Methylsiloxanes were the typical organic components in the raw wastewater and most of them were removed after treatment.