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ObjectiveTo isolate and identify a bacteriophage of Enterococcus faecalis and to analyze its biological characteristics.MethodsThe host bacteria was isolated from the process of yak slaughtering and identified by 16S rRNA sequencing. The bacteriophage was isolated from the environmental sewage and was purified. The titer of bacteriophages was determined using the double-layer plate method. The morphology of bacteriophage was observed by transmission electron microscopy； the bacteriophage lysis profiles， optimal infection complex， and one-step growth curve were determined； the effects of pH， UV irradiation， temperature， and organic solvents on bacteriophages have been studied. Furthermore， the lytic activity of the bacteriophage against the host bacteria was determined.ResultsThe host bacteria were identified as E. faecalis by 16S rRNA sequencing. A bacteriophage named P45 was isolated from sewage to lyse E. faecalis. Electron microscopy showed that the bacteriophage was a tadpole-shaped long-tailed bacteriophage， which has a hexahedral head and its length is （200±5） nm. The bacteriophage had obvious lysis effect on four strains of E. faecalis. Bacteriophage’s optimal multiplicity of infection was 0.1. The results of one-step growth curve showed that the incubation period was 50 min， the lysis period was 190 min， and the burst size was 1 PFU/cell. This bacteriophage survived at pH=2 to 3，which titers were 1.05×102 PFU/mL and 1.85×103 PFU/mL. At 75 ℃， this bacteriophage was completely inactivated. Bacteriophage’s titer was decreased by UV irradiation， and it was not sensitive to organic solvents.ConclusionThis bacteriophage has a good lysis effect and has potential application on the prevention or control of E. faecalis contamination.

Objective: To compare the regulatory effects of adlay (Coix lachryma-jobi L.) seeds fermented and not fermented by Lactobacillus plantarum NCU137 on immune and intestinal mucosal barrier function in mice induced by cyclophosphamide (CTX). Methods: BALB/c mice were randomly divided into four groups, including normal, CTX-induced model, non-fermented adlay seed (NFC) and fermented adlay seed (FC) treatment. The mice in the normal and CTX groups were orally administrated with 0.2 mL of physiological saline for 10 days, while those in the NFC and FC groups 0.2 mL of non-fermented and fermented adlay seeds for 10 days, respectively. The immunosuppressed mouse model was established by daily intraperitoneal injection of 100 mg/kg of CTX for the last three days of the administration period, while the normal group was intraperitoneally injected with the same volume of normal saline. Spleen index, the number of spleen T lymphocyte subsets, and the levels of cytokines and immunoglobulin were measured, histopathological examination of the small intestine was performed and intestinal mucosal barrier function was detected. Results: Compared with the CTX group, fermented adlay seeds significantly increased the spleen and thymus indexes of immunosuppressed mice, up-regulated the cluster of differentiation (CD) 4+/CD8+ ratio of spleen T lymphocytes, down-regulated the levels of spleen pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), and increased serum immunoglobulin (Ig) M and IgG levels. Moreover, fermented adlay seeds repaired small intestinal mucosal structure and up-regulated the gene expression of occludin and E-cadherin, and the effect was more pronounced than that of non-fermented adlay seeds. Conclusion: Coix lachryma-jobi L. seeds fermented by L. plantarum NCU137 have the potential to regulate immune and intestinal mucosal barrier function, which are expected to be developed into a novel health food with immunomodulatory function.

Objective To explore the application effect of comprehensive project training based on Miller’s “Pyramid” principle in nursing students’ strengthening training of nursing skills. Methods Convenient sampling method was used to select 112 students from 2 classes of nursing major in 2019 who were about to participate in clinical practice in the hospital. They were randomly divided into observation group (n=56) and control group (n=56). The observation group adopted the comprehensive training method based on Miller’s “Pyramid” principle. The control group used the traditional training method. The two groups of nursing students were compared in theory, skills, comprehensive cases and knowledge, skills application ability test results, evaluation of the two groups of nursing students in training behavior. Results The scores of theoretical knowledge, practical skills, comprehensive cases and application ability assessment in the observation group were higher than those in the control group (P < 0. 01). The behavioral performance evaluation scores of nursing students in the observation group were higher than those in the control group (P < 0. 01). The satisfaction score of nursing students in the observation group was higher than that in the control group(P < 0. 01). Conclusion The comprehensive project simulation training based on Miller "pyramid" principle is beneficial to improve the theoretical knowledge and operation ability of nursing students, improve the comprehensive ability of nursing students, standardize the nursing operation procedures of nursing students, and improve the quality of intensive training. (目的 探讨基于米勒“金字塔”原理的项目综合训练在护生护理技能强化练习中的应用效果。方法 采用便利抽样法抽取即将参加临床实习的2019级护理专业2个班级, 共112名护理学生为研究对象, 随机分为观察组56名和对照组56名。对照组采用传统实训练习方法; 观察组采用基于米勒“金字塔”原理的项目综合训练法。比较两组护生理论知识、操作技能、综合案例、临床实际应用能力考核成绩, 评价两组护生训练中的行为表现。结果 观察组理论知识、操作技能、综合案例和临床应用能力考核成绩均高于对照组, 差异有统计学意义(P＜0. 01)。观察组护生行为表现评价分均高于对照组, 差异有统计学意义(P＜0. 01)。观察组护生满意度评分高于对照组, 差异有统计学意义(P＜0. 01)。结论 基于米勒“金字塔”原理的项目综合模拟训练有利于提高护生理论知识和操作技能, 提高护生的综合能力, 能规范护生的护理操作程序, 提高强化实训质量。)

This paper reviewed the concept, content, intervention strategy, intervention significance of the trans-theoretical model and stages of change and its application in standard precautions among nurses, and summarized its application effect, aiming to provide reference for establishing the guidance of standard precautions for clinical nurses. (本文对行为阶段转变理论概念、内容、干预策略、干预意义及在护士准防护中应用现状进行综述, 总结分析其应用效果, 以期为临床护士标准防护指导提供参考依据。)

Acute kidney injury (AKI) is the most severe and fatal complication of sepsis resulting from infectious trauma. Currently, effective treatment options are still lacking. Dihydromyricetin is the main component extracted from Vine tea (Ampelopsis megalophylla Diels et Gilg). In our previous research, chitosan–tripolyphosphate-encapsulated nanoparticles of dihydromyricetin (CS-DMY-NPs) have been proven to have potential protective effects against cisplatin-induced AKI. Here, we investigated the protective effects and mechanisms of DMY and its nano-formulations against LPS-induced AKI by assessing pathological and inflammatory changes in mice. In mice with LPS-AKI treated with 300 mg/kg CS-DMY-NPs, the levels of creatinine (Cr), blood urea nitrogen (BUN), and KIM-1 were significantly reduced by 56%, 49%, and 88%, respectively. CS-DMY-NPs can upregulate the levels of GSH, SOD, and CAT by 47%, 7%, and 14%, respectively, to inhibit LPS-induced oxidative stress. Moreover, CS-DMY-NPs decreased the levels of IL-6, IL-1β, and MCP-1 by 31%, 49%, and 35%, respectively, to alleviate the inflammatory response. TUNEL and immunohistochemistry showed that CS-DMY-NPs reduced the number of apoptotic cells, increased the Bcl-2/Bax ratio by 30%, and attenuated renal cell apoptosis. Western blot analysis of renal tissue indicated that CS-DMY-NPs inhibited TLR4 expression and downregulated the phosphorylation of NF-κB p65 and IκBα. In summary, DMY prevented LPS-induced AKI by increasing antioxidant capacity, reducing inflammatory responses, and blocking apoptosis, and DMY nanoparticles were shown to have a better protective effect for future applications. [ABSTRACT FROM AUTHOR]

This study explores the influence of wettability surfaces on cavitation inception and evolution in high-speed centrifugal pumps used for thermal energy storage and transfer systems through numerical simulations. The simulations were conducted using the Kunz mass transfer model implemented in Fluent, combined with the Eulerian multiphase flow approach and the shear stress transport k–ω turbulence model. The cavitation dynamics were analyzed across contact angles ranging from superhydrophilic to superhydrophobic conditions. The results demonstrate that superhydrophobic surfaces delay cavitation onset compared to hydrophilic ones, reducing the critical cavitation coefficient by at least 28%. At flow rates of 1.11 Q0 and 0.89 Q0, cavitation numbers show distinct trends, with superhydrophobic surfaces enhancing cavitation stability and reducing the frequency of cavitation shedding. The reentrant jet dynamics are also affected, with increased hydrophobicity weakening the jets and stabilizing cavitation zones. This research aims to advance the understanding of using surface wettability to manage cavitation in high-speed centrifugal pumps, thereby improving the performance and reliability of thermal energy storage and transfer systems. [ABSTRACT FROM AUTHOR]

The expansion of vermiculite using microwave irradiation is an environmentally friendly and efficient method that can enhance the material's adsorption performance. This study investigated the microwave irradiation of vermiculite with five different particle sizes (4/2/1/0.5/0.2 mm) and found that the adsorption capacity for Pb2+ increased with larger particle sizes. The equilibrium adsorption capacity reached 15.98 mg/g at 4 mm, representing a 45.01% improvement compared to 0.2 mm. The pseudo-second-order kinetic model effectively described the adsorption kinetics. No significant differences were observed in the specific surface area and pore size distribution of all samples. Thermogravimetric quantitative analysis revealed that larger particle sizes retained interlayer water more effectively. As the particle size decreased, the interlayer water content generally showed a decreasing trend. Fourier-transform infrared spectroscopy analysis also indicated that the -OH groups in larger particle sizes exhibited higher stability. The results suggest that the high content and stability of -OH groups may be key factors in the enhanced adsorption performance for Pb2+. This provides new insights for the preparation of environmentally friendly adsorbent materials rich in hydroxyl groups. [ABSTRACT FROM AUTHOR]

Enhanced geothermal systems (EGSs) are expected to be one of the most promising methods of supplying energy to meet the world's increasing energy demand. However, little attention has been paid to the influence of the number of production wells on the heat extraction performance of an EGS. A series of numerical simulations is organized in this work with three cases: Case 1 (one production well), Case 2 (two production wells), and Case 3 (three production wells). The results indicate that a slight temperature difference exists among the three simulation cases at the planes X-Y (Z = 0) and Y-Z (X = 0), while Case 1 ensures a greater cooling area, and the more production wells, the smaller the cooling area during the heat extraction in plane X-Z (Y = 0). In addition, the continuous injection of cooling water from the injection well and its arrival at different reference points enable the temperature at each point to declining with a variable amplitude of variation. This work also sets an efficiency (ef) to investigate the temperature variation in the EGS, where Case 1 exhibits a similar variation as Case 2, which is also similar to Case 3. It is hoped that this work will play a guiding role in EGS-related exploration and exploitation. [ABSTRACT FROM AUTHOR]

The space of production well plays a crucial role in the heat extraction performance of the Enhanced Geothermal System (EGS), which have the potential to meet the growing global energy demand as a reliable energy source. Nonetheless, there has been insufficient research and attention focused on comprehending the impact of the space of production well on the efficiency and effectiveness of EGS. In this work, a series of numerical simulations were conducted to assess the impact of the space of production well on heat extraction efficiency in EGS. Three different cases were considered: Case 50 with 50 m production well spacing, Case 100 with 100 m production well spacing, and Case 150 with 150 m production well spacing. At the X-Y plane and Y-Z plane, the simulation results indicated that there were slight differences in temperature variation among the Case 50, Case 100 and Case 150. And the cooling area decreasing as the spacing of production wells decreased. Moreover, the delivery of cooling water via the injection well and its subsequent distribution to various reference points lead to a decline in temperature at each point, albeit with varying degrees of variation. Besides, the established efficiency (ef) for Case 50 is smaller than the Case 100 and Case 150 during the last 15 years. These findings contribute valuable insights to the exploration and exploitation of EGS systems and can serve as a guide for further research in this field. [ABSTRACT FROM AUTHOR]