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Background: Nosocomial transmission of Clostridioides difficile infection (CDI) has been documented in Ningbo, China. However, data on molecular characteristics, clonal transmission, and risk factors of CDI in this region remain limited. Methods: A cross-sectional study enrolled hospitalized patients with diarrhea during September to November 2021. Stool samples from all patients were tested for C. difficile , and isolated strains underwent toxin gene identification, genotyping, and antibiotic susceptibility testing. Whole-genome sequencing and epidemiological variables were analyzed in patients infected with C. difficile strains of the same sequence types (STs) to identify nosocomial transmission and risk factors for CDI. Results: Of the 907 investigated patients, 115 (12.7%) had microbiologically proven CDI, as their diarrhea was associated with toxigenic C. difficile strains, which comprised 106 A+B+CDT−, 3 A−B+CDT−, and 6 A+B+CDT+. Predominant genotypes (ST2, ST3, ST35, and ST54) exhibited distinct antibiotic resistance patterns. ST54 strains showed higher resistance to erythromycin (100%) but lower resistance to moxifloxacin (18.2%) and gatifloxacin (18.2%) (χ 2 = 10.24–16.65, p < 0.05). ST35 strains exhibited higher resistance to ciprofloxacin (66.7%) and tetracycline (33.3%) than other STs (χ 2 = 13.30–20.19, p < 0.05). Genomic and epidemiological analysis revealed two nosocomial clonal transmission events caused by 5 ST35 strains (with ≤2 single nucleotide polymorphism differences), elucidating clonal transmission among different floors and buildings within the hospital. Prolonged hospitalization (> 10 days) (odds ratio [95% confidence interval], 1.76 [1.05–2.93]) and penicillin-class antibiotics (1.69 [1.11–2.58]) were risk factors for CDI, with the latter being an independent risk factor (1.57 [1.02–2.42]). For C. difficile ST35 infection, intensive care unit (12.00 [2.77–52.05]) and neurology departments (8.08 [1.46–44.65]) admissions were risk factors, with the latter as an independent risk factor (1.56 [1.01–2.40]). Conclusion: Multiple C. difficile genotypes with varied antibiotic resistance patterns circulated in Ningbo, with ST35 causing nosocomial clonal transmission among different floors and buildings within the hospital. These findings and the identified risk factors necessitate enhanced surveillance and infection control in the region. [ABSTRACT FROM AUTHOR]

The fatigue properties of 12 mm Q890D high strength steel welded joint by hybrid laser-arc welding and their influencing factors were investigated in detail. The results showed that the fatigue limit of the welded joint was 406 MPa at two hundred thousand cycles load conditions, which was 45% of the yield strength of the base metal (BM). The welded joint could be divided into three layers, i.e., the backing layer, the filling layer, and the covering layer from the bottom to the top of the welded joint. The fatigue crack was initiated at the weld metal (WM) of the covering layer, then extended down to the WM and the heat affected zone of the filling layer, and finally fractured at the BM along the 45° direction. This was because that the BM consisted of massive polygonal ferrites and small granular carbides, while the WM was composed of martensite with a high density of dislocations. Additionally, the average hardness of the WM was 415 HV, which was 20% higher than that of the BM. Compared with the soft BM, the hardness and the strength of the WM were relatively high, resulting in higher resistance of the WM to the fatigue crack propagation. [ABSTRACT FROM AUTHOR]

Pain and inflammation are associated with the pathophysiology of different clinical conditions. The Lysimachia capillipes Hemsl. capilliposide (LCc) is the main bioactive component of this Chinese medicinal herb, which is widely used as a remedy for the treatment of colds and arthritis. This study investigated the analgesic and antiinflammatory activities of LCc in an animal model. LCc had no significant influence on the spleen, lung, liver and stomach coefficients in mice. Pharmacological studies showed that LCc at all doses (40, 60 and 90 mg/kg) increased the latency period of paw licking induced by thermal stimulation, and at the dose of 40 mg/kg it significantly suppressed abdominal writhing episodes of mice induced by intraperitoneal (i.p.) injection of acetic acid. LCc also had antiinflammatory effect on inflammation models. Doses of 60 and 90 mg/kg suppressed paw edema induced by subcutaneous (s.c.) injection of carrageenan. Mechanistic studies revealed that the antiinflammatory effect of LCc was associated with inhibition of the production of malondialdehyde (MDA), prostaglandin E2 (PGE2), tumor necrosis factor (TNF-α), cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) in paw tissue of carrageenan-injected mice. These results show that LCc has analgesic and antiinflammatory effects in mice.

To address the high energy consumption of the carbon capture and storage process in the shipping industry, the effects of several commonly used commercial catalysts, such as HZSM-5-25, γ-Al2O3, and SiO2, as well as a self-prepared catalyst, Zr-HZSM-5-25, on the regeneration of MEA solution and MEA + MDEA mixed solution were investigated in this paper. The results showed that Zr-HZSM-5-25 had the best catalytic effect on the regeneration process of the MEA aqueous solution, which could increase the instantaneous maximum CO2 regeneration rate of the MEA-rich solution by about 8.25% and the average regeneration rate by about 5.28%. For the MEA + MDEA mixed solution, the reaction between tertiary amine MDEA and CO2 produced a large amount of HCO3− in the reaction system, which could accelerate the release of CO2 to a large extent, which resulted in the catalytic effect of the Zr-HZSM-5-25 catalyst on the regeneration process of the mixed amine solution being significantly lower than that on the single MEA solution, with an increase of 4.91% in the instantaneous maximum regeneration rate. This instantaneous maximum regeneration rate was only increased by 4.91%. While Zr-HZSM-5-25 showed a better performance in the bench-scale test, it reduced CO2 regeneration energy consumption by 7.3%. [ABSTRACT FROM AUTHOR]

In this study, luteolin (LUT) was used as an emulsifier, benzyl isothiocyanate (BITC) as a model of nutrient delivery, and different oils [corn oil (CO), linseed oil (LO), and Antarctic krill oil (AKO)] with different carbon chain lengths and unsaturated double bond numbers as oil phases to construct Pickering emulsions. The rheological properties, photostability, storage stability, microstructure, oxidation stability, and BITC retention of Pickering emulsions were investigated to clarify the effects of different oil phases with carbon chain length and unsaturated double bond content on the properties of LUT-based Pickering emulsions. Results showed that the photostability of LUT-based Pickering emulsion was not affected by the different carbon chain lengths and unsaturated double bond content in the oil phases. Compared with LUT-CO and LUT-LO Pickering emulsion, LUT-AKO Pickering emulsion had the highest apparent viscosity and most uniform spatial structure. After 14 days of storage, the average particle size of LUT-AKO Pickering emulsion was the smallest [(213.47±2.30) nm], and the absolute value of Zeta potential and the embedding rate of BITC were the highest, reaching (42.73±1.96) mV and (65.25±1.45)%, respectively. The oxidation stability of LUT-AKO Pickering emulsion was slightly lower than those of other Pickering emulsions because of the strong AKO reactive activation. This study identified that AKO with a longer carbon chain was more suitable for preparing stable Pickering emulsions. This research provides a theoretical reference for expanding the application of LUT-based Pickering emulsions with different oil phases. [ABSTRACT FROM AUTHOR]

The net shell is a widely utilized large-span space structure known for its aesthetically pleasing design and uniform load distribution, as well as serving as a prominent architectural landmark. In recent years, the impact resistance research of mesh and shell structures has garnered increased attention due to the accumulation of local conflicts. In this study, a parametric model of the spherical mesh shell was developed with Rhino software, and a numerical analysis model for a K8 mesh shell was established through the application of the ABAQUS finite element analysis software. Subsequently, the proposed numerical analysis method for the impact test was applied to validate its accuracy. The research also explored various dynamic constitutive models, such as Cowper-Symonds, Johnson-Cook, modified temperature term Johnson-Cook, and modified strain term and temperature term Johnson-Cook, with the assessment of their impact on the numerical simulation of impact resistance. Based on the impact dynamic response of the spherical net shell of different materials, the selection of an appropriate dynamic constitutive model for the numerical simulation of impact resistance in the spherical net shell was the MJ-C model. The comparative analysis of different materials, including Q235B, Q355B, Q460D, and 6061-T6, indicated that when the impact material failed to penetrate the structure instantly, the improvement of the material strength would enhance the impact resistance of the structure. On the other hand, when the impact material managed to penetrate the structure instantly, the material strength would not significantly help mitigate the damage. Notably, brittle materials, such as aluminum alloy, exhibited a distinct absence of a pronounced yield stage compared with low-carbon steel, which ultimately led to a relatively abrupt deformation. [ABSTRACT FROM AUTHOR]