Fusion bonding is understood to be the decisive mechanism for the interlayer strength in extrusion additive manufacturing. This study links the characteristic temperatures of semicrystalline thermoplastics, namely, PA6 with 40% carbon fibers, to the bond formation in respect to real-world processing conditions. Based on theoretical investigations, a process window is proposed for bonding to occur without polymer degradation. This range from the glass transition to the initial degradation temperature was determined through differential scanning calorimetry and thermogravimetric analysis. A second process window for optimal bonding is proposed from the extrapolated onset crystallization temperature, T eic , to the melt temperature, T m . The validation of these process windows was conducted by bending tests according to DIN EN 178. T m was confirmed as the upper limit, with the part's geometric integrity compromised at higher temperatures. T eic had to be refuted as lower limit as no discrete reduction in bond strength was determined in alignment with T eic . Authors suggest the lower limit is defined by the lowest substrate temperature to lead to interface temperatures above the onset of melt temperature. By utilizing thermal analyses, less time and resources are required to detemine a suitable process window for extrusion additive manufacturing.

Background: Hand hygiene (HH) is considered the most important measure to tackle the transmission of healthcare-associated pathogens. However, compliance with recommendations is usually low and effective improvement strategies are needed. We aimed to assess the effectiveness of an intervention targeting hand hygiene promotion among healthcare workers (HCWs). Methods: We conducted a pre-post interventional study design in the university hospital Sahloul, Sousse, Tunisia, from January 2015 to December 2016. The intervention program consisted of training sessions and distribution of posters of hand hygiene guidelines. To assess the evolution of HH observance at pre-and post-intervention, the same observation form was distributed and collected at healthcare workers' workplace. Results: Of the 1201 and 1057 opportunities for hand hygiene observed among all categories of HCWs, overall compliance enhanced significantly from 32.1 to 39.4% (p < 0.001) respectively at pre-and post-intervention. Nurses were the most compliant with a significant improvement from 34.1 to 45.7% (p < 0.001) respectively at pre-and post-intervention. Furthermore, analysis by department showed significant improvement of compliance in orthopedic department (p < 0.001), maxillofacial-surgery department (p < 0.001), pediatrics department (p = 0.013), and emergencies (p = 0.038). Conclusion: This study showed the feasibility and effectiveness of a health-setting-based intervention to enhance hand hygiene observance in the context of a developing country.

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Background Although efforts to manage coronavirus disease 2019 (COVID-19) pandemic have understandably taken immediate priority, the impacts on traditional healthcare-associated infection (HAI) surveillance and prevention efforts remain concerning. Aim To describe trends in HAIs in a Tunisian university hospital through repeated point prevalence surveys over 9 years, assess the impact of measures implemented for COVID-19 pandemic, and to identify associated factors of HAI. Methods The current study focused on data collected from annual point prevalence surveys conducted from 2012 to 2020. All types of HAIs as defined by the Centers for Disease Control and Prevention (CDC) were included. Data collection was carried out using NosoTun plug. Univariate and multivariate logistic analysis were used to identify HAI risk factors. Results Overall, 2729 patients were observed in the 9 surveys; the mean age was 48.3 ± 23.3 years and 57.5% were male. We identified 267 infected patients (9.8%) and 296 HAIs (10.8%). Pneumonia/lower respiratory tract infections were the most frequent HAI (24%), followed by urinary tract infection (20.9%).The prevalence of infected patients increased from 10.6% in 2012 to 14.9% in 2020. However, this increase was not statistically significant. The prevalence of HAIs increased significantly from 12.3% to 15.5% ( P =.003). The only decrease involved is bloodstream infections (from 2% to 1%). Independent risk factors significantly associated with HAI were undergoing surgical intervention (aOR = 1.7), the use of antibiotic treatment in previous 6 months (aOR = 1.8), peripheral line (aOR=2), parenteral nutrition (aOR=2.4), urinary tract within 7 days (aOR=2.4), central line (aOR = 6.3), and prosthesis (aOR = 12.8), length of stay (aOR = 3), and the year of the survey. Young age was found as protective factor (aOR = .98). Conclusion Contrary to what was expected, we noticed an increase in the HAIs rates despite the preventive measures put in place to control the COVID-19 pandemic. This was partly explained by the vulnerability of hospitalized patients during this period.