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In this study, oxide dispersion strengthened (ODS) ferritic steels with nominal composition of Fe–14Cr–2W–0.35Y2O3 (14Cr non Zr-ODS) and Fe–14Cr–2W–0.3Zr–0.35Y2O3 (14Cr–Zr-ODS) were fabricated by mechanical alloying (MA) and hot isostatic pressing (HIP) technique to explore the impact of Zr addition on the microstructure and mechanical properties of 14Cr-ODS steels. Microstructure characterization revealed that Zr addition led to the formation of finer oxides, which was identified as Y4Zr3O12, with denser dispersion in the matrix. The ultimate tensile strength (UTS) of the non Zr-ODS steel is about 1201 MPa, but UTS of the Zr-ODS steel increases to1372 MPa, indicating the enhancement of mechanical properties by Zr addition.

In the present work, specimens prepared from coarse grained low carbon steel with different prestrains were baked and then, their bake hardening (BH) property and internal friction were determined. TEM was used to characterize the dislocation structure in BH treated samples. The measurements of internal friction in prestrained samples and baked samples were carried out using a multifunctional internal friction apparatus. The results indicate that, in coarse grained low carbon steel, the bake hardening properties (BH values) were negative, which were increased by increasing the prestrain from 2 to 5%, and then were decreased by increasing the prestrain from 5 to 10%. In the specimen with prestrain 5%, the BH value reached the maximum value and the height of Snoek-Köster peak was observed to be the maximum alike. With increasing the prestrain, both of the BH value and Snoek-Köster peak heights are similarly varied. It is concluded that Snoek-Köster and dislocation-enhanced Snoek peaks, caused by the interactions between interstitial solute carbon atoms and dislocations, can be used in further development of the bake hardening steels.

Purpose: This study aims to summarize the latest and best evidence on central venous access device-related thrombosis (CRT) in hospitalized children, which provides theoretical support for standardizing the preventive care practice of CRT in hospitalized children. Methods: Relevant guidelines, systematic reviews and expert consensuses were reviewed through ten guideline websites, six professional association websites and seven databases. The literature evaluation was conducted, and the best evidence from qualified studies was extracted and summarized. Furthermore, the best evidence was summarized through expert consultation and localized for the preventive care practice of CRT in hospitalized children in China. Results: A total of 14 topics and 68 best evidence were collected, including personnel qualification and quality management, pediatric patient selection, risk assessment, central venous access device (CVAD) selection and use, tip position, catheter maintenance, basic prevention, drug prevention, imaging examination, health education, nursing records, follow-up, CVAD removal and others. Conclusion: In this study, the best evidence based on evidence-based nursing was summarized, and expert consultation was adopted to localize the best evidence collected. It is of great significance to standardize the clinical practice of pediatric nurses and ensure the effectiveness of CRT preventive care for hospitalized children, thus guaranteeing the safety of hospitalized children with CVAD catheterization. [ABSTRACT FROM AUTHOR]

Simple Summary: Dietary energy level impacts rumen function and the microflora in ruminants, which are closely related to their growth and well-being. This study explored how dietary energy levels affect sheep's growth performance, nutrient digestibility, rumen fermentation, barrier function, and microflora. Our findings indicated that the average daily weight gain and nutrient digestibility improve with the increase of dietary energy. Meanwhile, the concentration of total volatile fatty acids and propionate in rumen increased, which indicated the enhancement of rumen fermentation. The content and expression of tight junction proteins, which represents rumen barrier function, increased with the increase of dietary energy. In addition, the bacterial diversity in rumen decreased, and the relative abundance of some bacteria like Prevotellaceae, Muribaculaceae, Saccharofermentans, Prevotella and Succiniclasticum changed at the family and genus levels. Ultimately, the growth performance, fermentation characteristics and barrier function were the best when the daily dietary metabolizable energy was 9.8–10.4 MJ/kg. This study revealed the complex interaction between diet, microbiota, and rumen health, ultimately guiding the development of more effective and scientifically informed animal feeding strategies. Dietary energy is crucial for ruminants' performance and health. To determine optimal dietary energy levels for growing sheep, we evaluated their growth performance, nutrient digestibility, rumen fermentation, barrier function, and microbiota under varying metabolic energy (ME) diets. Forty-five growing Yunnan semi-fine wool sheep, aged 10 months and weighing 30.8 ± 1.9 kg, were randomly allocated to five treatments, each receiving diets with ME levels of 8.0, 8.6, 9.2, 9.8 or 10.4 MJ/kg. The results showed that with increasing dietary energy, the average daily gain (ADG) as well as the digestibility of dry matter (DM) and organic matter (OM) increased (p < 0.05), while the feed conversion ratio (FCR) decreased linearly (p = 0.01). The concentration of total VFA (p = 0.03) and propionate (p = 0.01) in the rumen increased linearly, while rumen pH (p < 0.01) and the acetate–propionate ratio (p = 0.01) decreased linearly. Meanwhile, the protein contents of Claudin-4, Claudin-7, Occludin and ZO-1 as well as the relative mRNA expression of Claudin-4 and Occludin also increased (p < 0.05). In addition, rumen bacterial diversity decreased with the increase of dietary energy, and the relative abundance of some bacteria (like Saccharofermentans, Prevotella and Succiniclasticum) changed. In conclusion, increasing dietary energy levels enhanced growth performance, nutrient digestibility, rumen fermentation, and barrier function, and altered the rumen bacterial community distribution. The optimal dietary ME for these parameters in sheep at this growth stage was between 9.8 and 10.4 MJ/kg. [ABSTRACT FROM AUTHOR]

In the present study, the welding thermal cycle of magnesium-treated EH36 steel was simulated by a thermal simulation experiment machine. The effects of welding heat input on the microstructure and low temperature toughness of the welded joint were studied, and the mechanism of acicular ferrite nucleation induced by MgAl 2 O 4 inclusion was revealed. The results showed that, when the welding heat input of 150 kJ/cm, 250 kJ/cm and 350 kJ/cm was utilized, the microstructure of heat affected zone in the experimental EH36 steel consisted of grain boundary ferrite, acicular ferrite, granular bainite, and a small amount of pearlite, but the volume fraction and grain size of each independent microstructure were different. With the increase of welding heat input, the content of acicular ferrite and granular bainite decreased, the content of grain boundary ferrite increased, and the average grain size increased, whereas the low temperature toughness of the experimental EH36 steel welded joint reduced from 174 to 67 J. Furthermore, MgAl 2 O 4 inclusions can induce acicular ferrite nucleation, whereas the nucleation mechanism is a combination of low lattice mismatch and low interfacial energy. [ABSTRACT FROM AUTHOR]

In this paper, the solid solution and precipitation behavior of inclusions on the surface and 1/2 thickness of the tested steel plate under the condition of welding heat input of 400 kJ/cm is investigated by using laser confocal experiments with hot-rolled state DH36 ship plate steel as the research object, and the mechanism of the effect of inclusions on the phase transformation of an acicular ferrite is revealed. The results show that the inclusions of the tested steel are mainly composed of Oxide-MnS, MnS, Oxide, TiN, Spinel, etc. The amount of inclusions on the surface of the tested steel plate is significantly higher than that at the 1/2 thickness position. During the heating stage, the small inclusions on the surface immediately disappeared, and the large inclusions gradually solidified in the matrix; atomic diffusion occurred at the bond between the inclusions and the matrix; while the small inclusions at the 1/2 thickness position gradually disappeared at the beginning of the heating stage, and the inclusions began to precipitate and grow when the temperature was increased to 990 °C. The acicular ferrite preferentially nucleates and grows near the boundary of the inclusions during the post-weld cooling stage, and its growth ends when two acicular ferrites cross. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the impact of dietary energy and protein levels on the meat quality and metabolomic profile of Yunshang black goats. For this, 80 Yunshang black goats (male, 6 months old, with a mean live body weight of 35.82 ± 2.79 kg) were used in a completely randomized design with a 2 × 2 factorial dietary arrangement. The dietary treatments were (1) high energy (9.74 MJ/kg) with high protein (12.99%) (HEHP), (2) high energy (9.76 MJ/kg) with low protein (10.01%) (HELP), (3) low energy (8.18 MJ/kg) with high protein (13.04%) (LEHP), and (4) low energy (8.14 MJ/kg) with low protein (10.05%) (LELP). The experiment lasted 64 days, including 14 days for dietary adaptation and a 50-day feeding trial. At the end of the experiment, four animals from each treatment were slaughtered to assess their meat quality and metabolomic profiles. The pH value was greater for the goats fed the LELP diet compared with the other treatments. The LEHP-fed group's meat was brighter (L*) than that of the other three groups. The HEHP-fed group had considerably more tender meat (p < 0.05) compared with the LEHP-fed group. Moreover, 72 and 183 differentiated metabolites were detected in the longissimus muscle samples by using gas chromatography–mass spectrometry and liquid chromatography–tandem mass spectrometry, respectively. The hydropathy and volatilities of raw meat were different (p < 0.05), suggesting changes in the meat flavor because of the dietary treatments. Based on the results, it can be concluded that feeding a high-energy- and high-protein-containing diet improved the tenderness, flavor, and fatty acid contents of mutton. [ABSTRACT FROM AUTHOR]

This article has investigated a 60 mm Ca‐treated Q550 steel used for high‐heat input welding. The results have shown that the Ca‐type inclusions account for 70% of the inclusions in the steel which are mainly CaAlMg type, Ca–Al type, and a small amount of CaS type while the non‐Ca‐type inclusions are mainly FeCO. After undergoing the welding thermal cycle, the number of Ca‐containing inclusions above 2 μm in size is decreased while the number of non‐Ca‐containing inclusions below 1 μm (mainly FeO) is increased significantly. However, the total area of inclusions is decreased. It has been found out that the CaAlSO‐type inclusions undergo "diffusion" of O element to the surroundings during the thermal cycle, forming a ring‐shaped oxygen‐rich zone and carbon‐rich zone which promotes the nucleation of acicular ferrite. In contrast, the CaAlMgSO‐type inclusions undergo "decomposition" during the thermal cycle which forms a group of inclusions with different sizes and types, promoting nucleation of multioriented acicular ferrite. [ABSTRACT FROM AUTHOR]