67 research outputs found

    Effect of Mn Addition and Heat Treatment on the Corrosion Behaviour of Mg–Ag–Mn Alloy

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    The high corrosion sensitivity and the potential bio-toxicity of Mg-Ag alloys limit their wide applications for the production of implanted devices. In the present work, Mn is added into the Mg-Ag alloy to optimize its corrosion behaviour. The corrosion behaviour of Mg-Ag-Mn alloys is investigated with the underlying microstructural factors examined. The Mg-Ag alloy with 2 wt. % Mn exhibits the highest corrosion resistance after post-casting heat treatment at 440 ⁰C. The addition of Mn results in α-Mn phase with the incorporation of Fe, which suppresses the cathodic activity of impurity Fe. Further, heat treatment of the cast alloys homogenizes the distribution of Ag and promotes the precipitation of α-Mn phase. The former removes Ag segregations as potential cathodes; the latter promotes a more uniform distribution of cathodes and, therefore, prevents localized corrosion.<br/

    Personal Involvement Moderates Message Framing Effects on Food Safety Education among Medical University Students in Chongqing, China.

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    This study explored whether the efficacy of food safety education interventions can be increased by message framing among medical university students, and demonstrated the role of personal involvement within the message recipient in moderating framed effects. A cross-sectional study of food safety message framing was conducted among medical university students (randomly selected 1353 participants). An online self-administered questionnaire was used to collect information. Wilcoxon rank-sum test and Ordered multivariate logistic regression were utilised in the data analyses. The present study showed significant differences in acceptance between the gain- and loss-framed groups ( < 0.001). Participants with higher personal involvement had higher acceptance than those with low personal involvement in gain- and loss-framed message models ( < 0.001). The acceptance of participants who were concerned about their health condition was higher than those who were neutral regarding their health condition ( < 0.001) and participants who suffered a food safety incident had higher acceptance than those who did not ( < 0.05). This study portrayed the selection preference of message framing on food safety education among medical university students in southwest China. Participants exposed to loss-framed messages had higher message acceptance than those exposed to gain-framed messages. Personal involvement may affect the food safety message framing. Public health advocates and professionals can use framed messages as a strategy to enhance intervention efficacy in the process of food safety education

    Effects of Goal-Framed Messages on Mental Health Education Among Medical University Students: Moderating Role of Personal Involvement.

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    Mental health problem among university students is an emerging public health issue, and mental health education has always been the focus of attention for universities. However, limited attention has been paid to the effect of students' acceptance of health messages. Previous studies have found that message framing plays a key role in the process of responding to health-promoting messages. In this backdrop, the study aimed to examine the effects of goal-framed messages on mental health education among medical university students and investigate the moderating role of personal involvement. A cross-sectional study was conducted on medical university students. An online self-administered questionnaire was used to collect data. Wilcoxon rank-sum test and ordinal logistic regression were used for data analysis. Results showed significant differences in message acceptance between the gain- and loss-framed groups ( < 0.001). Participants with high personal involvement had higher message acceptance than those with low personal involvement in gain- and loss-framed message models ( < 0.05). Specifically, participants who related to roommates with high intimacy had higher message acceptance than those who related to roommates generally ( < 0.05). Participants who were concerned about their health condition had higher message acceptance than those who were neutral about their health condition ( < 0.001). Evidence of advantages of gain- over loss-framed messages on mental health among medical university students was found. The hypothesis that personal involvement with a health issue affects the acceptance of message framing was supported. Public health advocates can use framed message as a strategy to improve the efficacy of intervention in mental health education

    Acupuncture for chronic, stable angina pectoris and an investigation of the characteristics of acupoint specificity: study protocol for a multicenter randomized controlled trial

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    BACKGROUND: Chronic stable angina pectoris (CSAP) is a common cardiovascular condition that endangers a patient’s life quality and longevity. As demonstrated in several clinical trials, acupuncture is attested to be effective for CSAP. Current trials are not adequate enough to provide high-quality evidence for clinical decision making, as a result of inadequate methodology design and small sample size. Notably, stark controversy toward acupoint specificity also exists in the clinical acupuncture trials for CSAP. Therefore, we designed the present study as a randomized controlled trial primarily to investigate the effectiveness of acupuncture in addition to routine care among patients with CSAP. Meanwhile, we examined whether acupoint on the disease-affected meridian (DAM) is superior to either acupoint on the non-affected meridian (NAM) or non-acupoint (NA), to further investigate the meridian-based characteristics of acupoint specificity. METHODS/DESIGN: This study was a multicenter, assessor and statistician blinded, randomized controlled trial in China. In this study, 404 participants in sum will be randomly assigned to four groups through central randomization in a 1:1:1:1 ratio. The whole study period is 20 weeks including a 4-week baseline period, a 4-week treatment period and a 12-week follow-up. Participants in the DAM group receive acupuncture stimulation at acupoints on the disease-affected meridian, and three different control groups will undergo acupuncture stimulation at the NAM, the non-acupoint and no intervention respectively, in addition to basic treatment. Participants in the acupuncture groups will receive 12 sessions of acupuncture treatment over 4 weeks, while the wait-listed (WL) group would receive free acupuncture treatment after the completion of the study. The outcome measures in this trial include the frequency of angina attack during 4 weeks as the primary outcome and eight other secondary outcomes. DISCUSSION: This trial will provide new and relatively high-quality evidence in acupuncture treatment for CSAP. Moreover, this trial may further validate the meridian-based characteristics of acupoint specificity by comparing the strength of acupoints on the disease-affected meridian versus that of the non-affected meridian, to further inspire optimization of acupuncture therapy for CSAP. TRIAL REGISTRATION: Clinical Trials.gov NCT0168623

    Prevalence and influencing factors of lower urinary tract symptoms in female nurses: a cross-sectional study based on TARGET

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    BackgroundEven though occupational women have a high incidence of lower urinary tract symptoms (LUTS), which seriously affect their daily work life, few large scale sample studies have provided empirical evidence to support this phenomenon among female nurses in China. Consequently, this article investigated female nurses who was presupposed to have a high prevalence of LUTS, which adversely exposes their health and patient safety to these risks. Additionally, it is considered important to explore the factors associated with LUTS in female nurses for patient care safety and nurse bladder health practice.ObjectivesThe purpose of this study was to assess the incidence of LUTS and symptoms-related risk factors among female nurses, to provide evidence for the prevention and control of LUTS.MethodsAn online survey recruiting 23,066 participants was carried out in a multicenter cross-sectional study in 42 hospitals from December 2020 to November 2022. Stepwise multivariate logistic regression analysis and nomogram were used to identify the factors associated with lower urinary tract symptoms. Besides, SPSS version 26.0, R version 4.2.2, and GraphPad Prism Version 8.3 software packages were used for statistical analysis.ResultsBased on the completion rate of the questionnaire which was 84.1% (n = 19,393), it was found that among 19,393 female nurses, the prevalence of LUTS was 67.71% and this rate was influenced by age, Body Mass Index (BMI), marital status, years of working, menstrual status, mode of delivery, history of breastfeeding, history of miscarriage, history of alcohol and coffee or tea consumption (p &lt; 0.05). Interestingly, we also find that in addition to the above mentioned factors, anxiety, depression, and perceived stress were also related to LUTS in female nurses (p &lt; 0.05).ConclusionGiven the high prevalence of LUTS among female nurses and their potential influencing factors, female nurses should focus on their reproductive health and develop good lifestyle habits. Thus, nursing managers should provide a warm and harmonious work environment and sensitize female nurses to increase their awareness about the importance of drinking clean water and urinating during work in a hygienic environment

    Design and Evaluation the Anti-Wear Property of Inorganic Fullerene Tungsten Disulfide as Additive in PAO6 Oil

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    Inorganic fullerene-like tungsten disulfide particles have been proved to have good anti-friction and anti-wear properties as lubricating materials. As far as we know, however, when it is used as a lubricant additive, its behavior and action mechanism in the friction process are rarely studied. Herein, IF–WS2 particles were synthesized by a Chemical Vapor Deposition (CVD) method. The effect of IF–WS2 particle concentrations in the PAO6 oil on the tribological behaviors was investigated with a four-ball wear machine at both 75 and 100 °C. Additionally, the analyzed morphology and composition of nanomaterials and worn surfaces were analyzed by Scanning electron microscopy (SEM), Transmission Electron Microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The friction behavior in actual working conditions was studied by a wear testing machine. The experimental results show that compared with the original PAO6 oil, at a dispersion of 0.25 wt in PAO6 oil, the IF–WS2 particles showed the best performance in terms of coefficient of friction, wear scar diameter and wear mass, which significantly reduced by 27, 43 and 87, respectively. At the same time, in the process of friction, it was found that IF–WS2 particles accumulated in the depressions to fill the scratches, and adsorption films and chemical films, including FeS2, WS2 and WO3, were formed on the worn surfaces to avoid the direct contact among the friction pairs more effectively, resulting in the improved anti-wear performances. Additionally, the addition of IF–WS2 particles effectively delayed the rise of lubricating oil temperature. In addition, dispersant span 80 can effectively improve the dispersion and stability of IF–WS2 in PAO6. This work provides us for understanding the effective lubrication mechanism of IF–WS2 particles in more detail and having a new acknowledge of the comprehensive performance of IF–WS2/PAO6 oil

    Preparation and Application of Starch/Polyvinyl Alcohol/Citric Acid Ternary Blend Antimicrobial Functional Food Packaging Films

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    Ternary blend films were prepared with different ratios of starch/polyvinyl alcohol (PVA)/citric acid. The films were characterized by field emission scanning electron microscopy (FE-SEM), thermogravimetric analysis, as well as Fourier transform infrared (FTIR) analysis. The influence of different ratios of starch/polyvinyl alcohol (PVA)/citric acid and different drying times on the performance properties, transparency, tensile strength (TS), water vapor permeability (WVP), water solubility (WS), color difference (ΔE), and antimicrobial activity of the ternary blends films were investigated. The starch/polyvinyl alcohol/citric acid (S/P/C1:1:0, S/P/C3:1:0.08, and S/P/C3:3:0.08) films were all highly transparent. The S/P/C3:3:0.08 had a 54.31 times water-holding capacity of its own weight and its mechanical tensile strength was 46.45 MPa. In addition, its surface had good uniformity and compactness. The S/P/C3:1:0.08 and S/P/C3:3:0.08 showed strong antimicrobial activity to Listeria monocytogenes and Escherichia coli, which were the food-borne pathogenic bacteria used. The freshness test results of fresh figs showed that all of the blends prevented the formation of condensed water on the surface of the film, and the S/P/C3:1:0.08 and S/P/C3:3:0.08 prevented the deterioration of figs during storage. The films can be used as an active food packaging system due to their strong antibacterial effect

    The Influence of Thermomechanical Treatment on the Corrosion Behaviour of 2a97 Al-Cu-Li Alloy

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    In the present work, the corrosion behaviour of 2A97 Al-Cu-Li alloy with different thermomechanical treatments is investigated using electron microscopy and electrochemical measurements. The various thermomechanical treatments allowed the assessing of the individual and synergistic influence of local plastic deformation and precipitation on the corrosion susceptibility and mechanism of the alloy. It is found thatin NaCl solution, corrosion of the alloys in T3 and T4 tempers occurs in the form of intergranular corrosion, which is closely associated with stored energy distribution. By contrast, the alloys in T6 and T8 tempers exhibit mainly intragranular corrosion due to high volume fractions of precipitates formed by artificial ageing
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