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[Display omitted] • 1. A modified creep crack opening displacement (CCTOD) theoretical model is presented firstly. • 2. A numerical simulation model of specimens with a crack tip is established. • 3. About 10% CTOD increment is induced by room temperature creep of specimen. • 4. The loads effect and load history can effect on the CCTOD at room temperature creep. The room temperature creep behavior of X80 pipeline steel has attracted increasing attention because it is considered to be the main cause of time-delayed failure in pipeline steel. The crack tip opening displacement (CTOD) is a general criterion to characterize the time-delayed failure and assessment safety of pipeline steel. However, there are few methods to demonstrate crack behavior of the pipeline steel caused by room temperature creep. Based on the traditional CTOD theoretical model, a modified creep crack tip opening displacement (CCTOD) theoretical model is presented to calculate the CCTOD from the crack mouth opening displacement (CMOD). The room temperature creep experiment with a single edge notched beam subjected to three-point bending creep load for 36 h at room temperature is performed to know more about the CCTOD of X80 pipeline steel. Based on a power-law time delayed relationship among creep strain, stress and time fitted from experiment results of tensile creep tests, the finite element model is also established to evaluation the CCTOD of pipeline steel at room temperature. It is found that there is about 10% CTOD increment caused by room temperature creep added to that of the traditional elastic and plastic CTOD which indicates that room temperature creep is also further blunted the crack tip of X80 pipeline steel. Meanwhile, The results will provide an approach for failure evaluation and an integrity guideline for X80 pipeline steel. [ABSTRACT FROM AUTHOR]

• Experimental analysis of the effect of room temperature creep on the fracture toughness of X80 pipeline steel. • The test data were fitted to a power-law equation which showed that after 36 h of creep at room temperature, the incremental crack tip opening displacement was approximately 0.0098 mm. • A time-dependent CTOD model was proposed regarding room temperature creep. And a pressure reduction strategy is proposed based on this criterion. The growing demand for energy consumption has led to the rapid development of high strength and high toughness pipeline steel technology, with fracture toughness being a crucial factor in evaluating the mechanical properties of pipeline steel. Despite experimental studies demonstrating that metallic materials, including pipeline steel, undergo creep at room temperature, the effects of room temperature creep (RTC) on pipeline steel fracture properties are still relatively unexplained. This study analyzes the impact of RTC on the fracture toughness of X80pipeline steel, using the X80pipeline steel base material as the research object. Firstly, the time-dependent change in crack notch opening displacement is added to the calculation formula for fracture toughness of three-point bending specimens, considering the effect of RTC. The test data is fitted to a power-law equation of the form, where k = 0.01423 and m = - 0.89651 , with the improved formula indicating an incremental CTOD of approximately 0.0098 mm after 36 h of RTC for X80 pipeline steel. Secondly, a time-dependent CTOD model is proposed based on the ductile defect growth model, with the plastic part derived from the D-B model and the creep part obtained by fitting the test data. The study proposes a CTOD criterion for RTC and a pressure reduction strategy based on this criterion, providing a reference for quantitatively assessing the fracture toughness of pipeline steel under RTC conditions. [ABSTRACT FROM AUTHOR]

Objective Posttraumatic immune disorder can cause complications including systemic inflammatory response syndrome (SIRS) and multiple-organ dysfunction syndrome (MODS). Cytotoxic granules containing perforin and granzyme-B (GrB) are released by cytotoxic CD8 + T lymphocytes, NK and γδT cells after major trauma. This prospective clinical study was designed to analyze the association between these immune components and complications after major trauma. Methods We retrospectively studied 48 patients aged between 16 and 65 years admitted within 90 min of major trauma (Injury Severity Score > 16) and surviving beyond 7 days, and 20 healthy controls. Blood samples were drawn on admission and after 1, 3 and 7 days. CD8 + T, NK and γδT cell counts in peripheral blood and the levels of perforin and GrB in these cells were analyzed by flow cytometry. Clinical aspects of MODS and SIRS were recorded daily. Results CD8 + T cell counts were not significantly different in patients with SIRS or uncomplicated group, but were depressed in the MODS group after trauma. However, NK cell counts in patients with MODS were significantly depressed only at day 7 after injury, and γδT cell counts were significantly depressed after trauma. Perforin levels in CD8 + T, NK and γδT cells in patients with MODS were depressed after trauma. GrB levels in NK, CD8 + T and γδT cells in patients with MODS were significantly depressed at 3 and 7 days post trauma. Conclusion Posttraumatic MODS is associated with early, sustained, and severe depression of lymphocytes. [ABSTRACT FROM AUTHOR]

Because of the increasingly environmental and health concerns over conventional polyurethanes that manifested by toxic isocyanates and unsustainable fossil-based polyols, there is a great interest in non-isocyanate polyurethanes (NIPUs) production from renewable biomass resources. Herein, under the concept of biorefinery, the sweet potato residue (SPR) from starch industry, rich in non-biological toxicity starch, holocellulose and vegetable protein, was considered as the raw material for the NIPUs. During the process, the crude SPR was first liquified into chain-extending homogeneous molecules that were enriched in active hydroxyl-groups, followed by undergoing epoxidation and carbonation. Then, the obtained cyclic carbonate precursor was crosslinked with amines for the final NIPUs. The as-prepared SPR-derived NIPUs exhibited attractive mechanical and thermodynamic properties. To test the applicability, the food preservation performances of the SPR-derived NIPUs was further investigated. After spray coating the NIPUs on the banana peel, the dark brown spots in the testing group were significantly reduced after half-month storage. Therefore, the SPR-derived NIPUs provides a foundation for the futural food packaging alternatives. [Display omitted] • Non-isocyanate polyurethane films were prepared using sweet potato residues. • The sweet potato residue was functionalized before crosslinking with amines. • The non-isocyanate polyurethane films exhibited good mechanical properties. • The non-isocyanate polyurethanes performances were dependent on the type of amines. • The non-isocyanate polyurethane films can be used for foods preservation. [ABSTRACT FROM AUTHOR]

Potentilla chinesis Ser. (Wei Ling Cai) was a food for humans and animals in China, as well as a traditional Chinese herb recorded in "ZhonghuaBencao". Aeromonas hydrophila NJ-35 (NJ-35) was a bacterial pathogen associated with high mortality rate in aquaculture. The purpose of the present work was to isolate and identify the anti-bacterial components against the NJ-35 from the extract of Wei Ling Cai, as well as explore the underlying anti-bacterial mechanism. The peak 3 was the most efficient anti-bacterial component in all collected peaks, and it was identified as (1 R ,2 S ,5 R ,6 S)-2,6-bis(3-ethyl-4-hydroxy-5-methoxyphenyl)-3,7-dioxabicyclo[3.3.0]octane (P-3) by high-resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR). The minimum inhibition concentration (MIC) of P-3 against NJ-35 was 0.125 mg/mL. The results of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) combined with NanoLC-ESI-MS/MS showed that, in the P-3- treated group, the proteins of phosphoglucomutase (PGM), pyruvate dehydrogenase E1 and alkyl hydroperoxide reductase subunit C (AhpC) were up-regulated, whereas, the porin and 30S ribosomal S3 were down-regulated. In addition, after the treatment of P-3 , the activity of alkaline phosphatase (AKP) and the membrane permeability were increased (P < 0.01). The results of scanning electron microscope (SEM) showed that P-3 made the NJ-35 shriveled, sunken, and wrinkled. Taken together, these results suggested the P-3 might be a promising anti-bacterial agent for pharmacological research, and Wei Ling Cai could be a food-borne treatment for the A. hydrophila infection in aquaculture. [Display omitted] • The Potentilla chinensis Ser. (Wei Ling Cai) could inhibit the growth of NJ-35. • The active anti-bacterial components were separated and identified as P-3. • The P-3 could destroy of the cell wall and cell membrane of NJ-35. • The P-3 could inhibit the protein synthesis of NJ-35. [ABSTRACT FROM AUTHOR]