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Traditional hot-dip galvanized coatings, typically single-silver in color, present increasing aesthetic challenges in diverse applications, while prevailing organic coating methods involve complex processes with high energy consumption and pollution emissions. In this study, a novel hot-dip process for in-situ synthesis of color coating on steel was proposed, capable of producing various uniform color coating. The microstructure of color coatings on steel was systematically examined, and an assessment of their corrosion and weather resistance was conducted. The results demonstrate the sequence of typical color variation is gold, purple, blue, cyan, red, green, and grey. By controlling the immersion temperature range, and regulating the final stable color of the oxide film. The coloration mechanism mainly is attributed to the light interference on the Mn oxide film. The cyan and brown coatings mainly consist of the dense rod-like ζ-FeZn13 phases which provide a structural foundation for corrosion resistance. Furthermore, the brown coating exhibited excellent weather resistance.

The corrosion behaviour of Nd alloyed magnesium alloy AZ80 in three simulated concrete pore solutions (SCPs) was studied using corrosion immersion tests and electrochemical tests. The study investigated the effects of the composition and pH of the SCPs on the corrosion properties of AZ80 and AZ80-1.0Nd using aluminum alloy AA6061 as a reference. The SCP1, SCP2, and SCP3 solutions were the simulated concrete pore solutions with different carbonation stages at pH 13.5, 12.5, and 9.7 respectively. The corrosion mainly in the form of localized corrosion, developed significantly along the transverse direction, and less in the vertical direction. AZ80 and AZ80-1.0Nd exhibited the best corrosion resistance in the SCP2 solution, which was attributed to the formation of a dense protective film on the surface. The corrosion in the high alkalinity SCP1 solution was first enhanced within 12 h and then somewhat decreased within 72 h attributed to the destruction and re-formation of the surface film. AA6061 corroded severely in the SCP1 solution and suffered significantly less corrosion in the SCP2 and SCP3 solutions. Nd alloying contributed to the reduced corrosion rates of AZ80 in the simulated concrete pore solutions, attributed to changes in the microstructure and electrochemical properties.

Based on the heat transfer analysis in the primary cooling region of large-size magnesium alloy flat ingot Direct-chill (DC) casting, a novel crystallizer structure for flat ingot electromagnetic DC casting was put forward, in which the primary cooling can be controlled independently from the secondary cooling, and the circumferential control of the primary cooling can be realized synchronously. The design and optimization of the inner sleeve material and thickness and the distribution of the primary cooling were also carried out. For the AZ31B flat ingot with a cross-section size of 1200 × 400 mm, the copper inner sleeve material was selected, and it is beneficial to control temperature gradient and mushy zone shape in flat ingot DC casting. A uniform temperature distribution can be obtained when the cooling intensity ratio of the wide and narrow faces is 1:1/3. Furthermore, the influence of casting process parameters on the mushy zone characteristic of 1200 × 400 mm flat ingot was studied by orthogonal planning of process parameters and numerical simulation methods. Simultaneously, the casting process parameters of other flat ingot sizes were determined, and AZ31B alloy DC casting flat ingots with section sizes of 750 × 440 mm, 1200 × 400 mm, and 1600 × 400 mm under industrial conditions were carried out, and the crack-free preparation of the above billets was successfully achieved.

Magnesium matrix composite is another competitive light metal matrix composite following aluminum matrix composite, with excellent application prospects in the aerospace and automotive fields. In this paper, the Mg - 3Y – xSiCp (x = 0, 1, 3, 5 wt%) composites are fabricated by stir casting with ultrasonic vibration followed by extrusion. The microstructure of the alloys is investigated by means of scanning electron microscopy (SEM) imaging and electron backscatter diffraction (EBSD) techniques. The results reveal that the composites have a finer grain size due to the particle promoted nucleation (PSN) mechanism. When the SiCp content is 3 wt%, the grain size is the smallest (0.76 μm), and the refinement rate is about 16.7%. Moreover, the addition of SiCp can inhibit the transformation from low-angle grain boundaries (LABGs) to high-angle grain boundaries (HABGs), thus hindering the dynamic recrystallization (DRX) of the alloy, which decreases from 55.7% to 15.4%. The reduction in the proportion of recrystallized grains in the composite leads to increasing the maximum intensity of the texture. In addition, the tensile properties and the strengthening mechanism of the alloys are investigated. The results show that the composites have higher ultimate tensile strength (UTS) and yield strength (YS) due to the combination of grain refinement and dislocation strengthening. When the SiCp content is 5 wt%, the UTS (291 MPa) and YS (283 MPa) increase by ∼12.7% and ∼17.1%, respectively, over the matrix alloy. However, the addition of SiCp causes more oxides and holes in the alloys, which leads to a fracture strain (δ) decrease in the composites.

Background: Accumulating research substantiated that tumor-associated macrophages (TAMs) have a significant impact on the tumorigenesis, progression, and distant metastasis, representing a novel target for various cancers. However, the underlying dynamic changes and interactions between TAMs and tumor cells remain largely elusive in colorectal cancer (CRC). Methods: We depicted the dynamic changes of macrophages using sing-cell RNA-seq data and extracted TAM differentiation-related genes. Next, we utilized the weighted gene co-expression network analysis (WGCNA) to acquire CMS-related modular genes using bulk RNA-seq data. Finally, we utilized univariate Cox and Lasso Cox regression analyses to identify TAM differentiation-related biomarkers and established a novel risk signature model. We employed quantitative real-time polymerase chain reaction (qRT-PCR) on CRC tissue samples and used immunohistochemistry (IHC) data frome the HPA database to validate the mRNA and protein expression of prognostic genes. The interaction of TAMs and each consensus molecular subtype (CMS) subpopulation was analyzed at the cellular level. Results: A total of 47,285 cells from single-cell dataset and 1197 CRC patients from bulk dataset were obtained. Among those, 6400 myeloid cells were re-clustered and annotated. RNASE1, F13A1, DAPK1, CLEC10A, RPN2, REG4 and RGS19 were identified as prognostic genes and the risk signature model was established based on the above genes. The qRT-PCR analysis indicated that the expression of RNASE1 and DAPK1 were significantly up-regulated in CRC tumor tissues. The cell-cell communication analysis demonstrated complex interactions between TAMs and CMS malignant cell subpopulations. Conclusion: This study presents an in-depth dissection of the dynamic features of TAMs in the tumor microenvironment and provides promising therapeutic targets for CRC.

ABSTRACT: Objectives: This study aims to explore the high-risk factors of carbapenem-resistant Enterobacteriaceae (CRE) infection of hospitalised patients in high-risk departments. Methods: This study is a multicentre, retrospective study. CRE screening positive patients from 1 January 2016 to 31 December 2018 of high-risk departments in five tertiary first-class teaching hospitals in Beijing collect the patients’ CRE test specimen information, CRE infection information and outcomes. The patients were divided into a colonisation group and an infection group for comparative analysis. A logistic regression model was established to explore the risk factors of CRE infection. Subgroup analysis was conducted according to invasive procedures and the type of the infection. Results: In total, 344 patients were included in this study, including 85 (24.71%) colonisation and 259 (75.29%) infection; 36.09% CRE colonisation converted to infection, and the mean conversion time from colonisation to infection was 6.5 (4.0, 18.8) days. Renal disease, granulocytosis, invasive procedures and the time from hospital stay to positive CRE were the risk factors for CRE infection. The subgroup analysis showed that the rate of CRE infection in the invasive group was higher than in the non-invasive group (P < 0.001), and the rate of exacerbation or death in the invasive group was also higher than in the non-invasive group (P = 0.019). The average length of ICU and hospitalisation in the healthcare-associated infection group were significantly higher than those in the community infection group, but there was no difference in the proportion of final exacerbation or death between them (P = 0.727). Conclusion: Kidney disease, granulocytosis, invasive procedures and CRE detection time are the risk factors for CRE infection. Carrying out CRE screening in patients as early as possible and taking effective intervention measures in time to avoid adverse consequences is all important.

Summary: Background: Postoperative complications and recurrence are major diffficulties in the flap techniques for the treatment of pilonidal sinus (PS), however, the risk factors remain unclear. While magnetic resonance imaging (MRI) offers the highest soft tissue resolution, few studies have applied MRI to investigate the basic parameters of PS. Methods: A total of 100 patients receiving Limberg flap (LF) or Karydakis flap (KF) surgery at the Sixth Affiliated Hospital of Sun Yat-Sen University were retrospectively analyzed, and the median follow-up period was 42 (range, 20–90) months. We performed a multivariate logistic analysis on the clinicopathological parameters and MRI data to identify risk factors for complications and recurrence. Results: The basic parameters of PS were obtained by MRI analysis. The multivariate analysis revealed a large longitudinal sinus diameter (OR = 1.020, 95%CI = 1.000–1.041) and sacrococcygeal dermal thickness (OR = 1.680, 95%CI = 1.142–2.472) to be independent risk factors for early complications. Meanwhile, a small sacrococcygeal fat thickness (OR = 0.923, 95%CI = 0.864–0.987) and a high BMI (OR = 1.291, 95%CI = 1.067–1.563) are independent risk factors for late complications and recurrence, respectively. Conclusion: We used MRI to measure the basic parameters of PS accurately, including size, volume, location and some key points of the surrounding tissues, and identified, besides the selection of surgical approach, some specific basic parameters of PS might be the risk factors for complications and recurrence after flap techniques.

Introduction: China emerged from the first wave of COVID-19 in a short period of time and returned to normal economic and living order nationwide, making China's entry into the post-COVID-19 epidemic period since April 2020. However, the COVID-19 epidemic had a great impact on young adults' psychological status and may continue into the post-epidemic period. The enormous economic, employment and entrepreneurship pressures of this period may exacerbate this negative impact. This study investigated the depression status of the young adults and put forward the suggestions on how to strengthen the psychological crisis intervention and social security to cultivate the resilience of the young adults after major public health emergencies. Methods: This study conducted a questionnaire survey to identify the prevalence of depressive symptoms and explore the associated factors of depressive symptoms among 1069 young adults in X City, Hubei province in September 2020. And the multistage stratified random sampling method was used for sampling. Depressive symptoms were measured using the 10-item version of the Center for Epidemiological Studies Depression Scale (CES-D-10). Descriptive statistics and logistic regression analysis were adopted for statistical analysis. Results: 1069 respondents (67.68% male; mean age = 28.87 ± 4.18 years; age range = 18–35 years) were included in final analyses. About 25.9% of the respondents reported depressive symptoms (CES-D-10 score = 7.28 ± 3.85). Age, marital status, employment status, monthly disposable income, the cognition, experience and social relationship of the COVID-19 epidemic, and regional discrimination were significantly associated with depressive symptoms. Being male (P = 0.025), age of 25–29 years (P = 0.011), having a household size with 4–5 (P = 0.01) and more than 8 (P = 0.012) family members, a little pessimism about the prospect of COVID-19 epidemic prevention and control (P = 0.044), often (P = 0.018) or always (P = 0.009) participation in anti-epidemic volunteer work were likely to lead to depressive symptoms. Conclusions: In the post-COVID-19 epidemic period, the psychological status of young people is generally stable, but some of them are depressed. Life, work and mental stress affect the generation of depressive symptoms among the young adults.

Mutations in the APP gene are popularly known as the second cause trigger the familial Alzheimer's disease (AD). We generated a human induced pluripotent stem cell (iPSC) line from the peripheral blood mononuclear cells isolated from an AD patient using non-integrative Sendai virus. The iPSC line highly expresses pluripotency markers, has the capacity to differentiate into the normal teratoma tissue, retains the APP mutation, and displays the normal karyotype. The iPSC line will provide a useful resource to study the pathogenesis and drugs screening of AD.

With the rapid growth of the automotive industry, a huge amount of tires have been produced, which inevitably led to the accumulation of scrap tires. A typical disposal routine is using scrap tires as a partial substitute for fine aggregate in concrete, producing so-called rubber concrete. However, the detrimental effects of rubber particles on concrete properties have been identified, which, to some content, hinders their broader application. The discrete fiber addition is shown to be effective in minimizing this detrimental effect, and this paper has therefore attempted to introduce macro fiber produced from waste glass fiber reinforced polymer (GFRP) into the rubber concrete system. Three series of specimens for compression, splitting, and flexural testing were tested. The test variables include concrete type (i.e., normal concrete, rubber concrete, and modified rubber concrete); and macro fiber content (i.e., 0–2 %). In addition, the inverse analysis is performed to transform the flexural test response into the tensile constitutive law of the fiber-reinforced concrete (FRC). The test results revealed macro fibers have little effect on the compressive strength of normal concrete and rubber concrete and a detrimental effect on that of modified rubber concrete. Incorporated fibers notably improve the splitting and flexural performance of normal concrete and rubber concrete. In addition, the cost and environmental impact analysis revealed that the addition of recycling products increases the concrete cost and results in a maximum reduction of carbon emissions by 17.3 % and embodied energy emissions by 80 %.

The G-H loop of the foot-and-mouth disease virus (FMDV) virion contains certain dominant immunogenic epitopes, as well as an arginine-glycine-aspartic acid (RGD) motif that is recognized by cell surface integrin receptors. Previous experiments indicate that it is critical to maintain virus structural integrity when inserting an exogenous epitope into the surface of an FMDV structural protein. However, it remains to be determined how factors such as different insertion positions affect interactions among the virus, cells and host immune system. In this study, one infectious cDNA clone of the swine FMDV Cathay topotype strain O/CHA/90 was constructed. Then, a FLAG marker (DYKDDDDK) was inserted upstream (–4) or downstream (+10) of the RGD motif to generate tagged viruses vFLAG-O/CHA/90 or vO/CHA/90-FLAG, investigating the possibility of expressing foreign antigen and effect on its immunogenicity. Compared to the parental virus, both tagged viruses exhibited similar plaque phenotypes, suckling mouse pathogenicity and antigenicity. Additionally, the FLAG tag insertion position did not change the use of integrin-mediated cell entry by the tagged viruses. Interestingly, both tagged vaccines protected pigs against challenge with the parental virus O/CHA/90 and induced immune responses against FMDV in BALB/c mice and pigs, but only vaccination with vFLAG-O/CHA/90 generated anti-FLAG antibodies. Our findings demonstrated that two sites (RGD–4 and RGD+10) tolerated the insertion of an exogenous gene in the swine FMDV O/CHA/90 strain. However, only RGD–4 was a novel and appropriate inserting site which could tolerate exogenous FLAG. The resultant tagged virus is a promising candidate for FMD vaccine which can be differentiating infected from vaccinated animals (DIVA).

In this study, chitosan-based silicon nanoparticles (Chsi-NPs) are prepared that primarily consists of C (57.9%), O (31.3%), N (5.6%), and Si (3.5%) and are 10-180 nm in size. We then explore the effect on the foliage applied on rice planted on soil contaminated with 104 mg·kg -1 arsenic (As); low (3 mg·L -1 )and high (15 mg·L -1 ) doses of the foliar Chsi-NPs are administered during the rice grain filling stage. The results showed that the higher dose foliar Chsi-NPs treatment reduced the As concentration in the grain by 61.2% but increased As concentration in the leaves by 47.1% compared to the control treatment. The foliar spraying of the Chsi-NPs inhibited As transport to the grain by facilitating the attachment of As to the cell wall, with higher doses of the foliar Chsi-NPs treatment increased by 8.7%. The foliar spraying of Chsi-NPs increased the malondialdehyde levels by 18.4%, the catalase activity by 49.0%, and the glutathione activity by 99.0%. These results indicated that the foliar Chsi-NPs application was effective for alleviating As toxicity and accumulation in rice. This study provides a novel method for effectively alleviating As accumulation in rice., (Copyright © 2022 Elsevier B.V. All rights reserved.)