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Abstract Background and objectives: In this research, the formation of chitosan-TiO2 nanocomposite and its antibacterial effect on Escherichia coli and staphylococcus aureus was investigated Material and Methods: to study the results, we used Scanning electron microscopy (SEM) and transition electron microscopy (TEM) images, infrared (IR) spectroscopy and ultraviolet-visible. Optical Density (OD) was also measured by spectrophotometer then the effect of this nano composite, in the vicinity of aforementioned bacteria, on the sterilized gauze in solid Muller Hinton Agar and TSB liquid mediums was assessed Results: The mentioned nanocomposite was formed with the composition of 4mg/ml Chitosan concentration and 2% titanium dioxide concentration. Finally, we observed that this nanocomposite near 100% could prevent bacterial growth and in the presence of this material did not grow any bacteria. Conclusion: chitosan-Tio2 Nanocomposite can be useful on culture medium and sterilized gauze to control pathologic bacteria. Key words: nanocomposite, nanochitosan, titanium dioxide, antibacterial, sterilized gauze

The present study aims to examine the vibrational behavior of buckled Functionally Graded (FG) circular plates under clamped and simply-supported edge conditions. To this end, von Kffarmffan assumptions were taken into account to incorporate geometric nonlinearity into Kirchho plate theory and derive the nonlinear governing equations of motion using Hamilton's principle. Critical buckling load and linear natural frequencies were first calculated using Generalized Differential Quadrature (GDQ) method. Next, the postbuckling characteristics of the circular plate were identified through direct solving of the nonlinear governing equations. Several comparative studies have confirmed the reliability of the proposed model. Finally, the fundamental natural frequency of the plate was evaluated for pre- and postbuckled configurations. This study also evaluated the effects of material property and boundary conditions on the static bifurcation diagram and natural frequency of the initial undeffected and buckled plate. According to the findings, the trend of the fundamental natural frequency changes with the applied radial load around the pre-buckled configuration differed from the one around the buckled configuration. [ABSTRACT FROM AUTHOR]

Abstract Diabetes mellitus is a global endemic with a rapidly increasing prevalence in both developing and developed countries. Recently, hemoglobin A1c has been recommended by the American Diabetes Associations as a possible substitute for fasting blood glucose for the diagnosis of diabetes, because it is an indicator of long-term glycemic control. Also, centrifugal microfluidic systems have good potential for use in the point of care testing systems. In this study, a centrifugal microfluidic disc was designed and manufactured to measure hemoglobin A1c in whole blood using an immunoturbidimetry based method. Also, a new passive valve, named septum valve, was presented to precisely control the entry and exit of reagents. This design comprises three inputs for injection of reagents and a blood sample, three septum valves, a two-part mixing chamber and a chamber to measure the absorbance of the sample based on the immunoturbidimetry method. Fourteen blood samples were tested using the manufactured disc, and the results were very congruous with the clinical data. By using the designed centrifugal microfluidic disc, the hemoglobin A1c in whole blood was measured in 8 min, with a standard deviation of ± 0.36% HbA1c. Graphical abstract fx1 Highlights • A microfluidic disc for measuring %HbA1c using immunoturbidimetry method was designed. • The ratio of HbA1c to total Hb was directly obtained and the process time was reduced. • A septum valve was presented to precisely control the entry and exit of the reagents. • The results show that the designed disc is beneficial as a point of care device. [ABSTRACT FROM AUTHOR]

Web 2.0 tools and emerging technologies offer learners an abundance of information and resources. This brings more flexibility and choices for learners to better control their learning and benefit from the various available learning materials in different forms. This has resulted in new learning practices and environments in higher education. Such technology-mediated learning environments which are more open, flexible, and student-centered or, as it is called, Personal Learning Environments (PLE). This paper describes PLE as a set of learner-defined tools and services in the ecology of Web 2.0 used by participants in three open online courses. The aim of the study was to find out how participants create and utilize their PLEs for searching, aggregating, creating and sharing content and learning resources, and being engaged in online learning networks and communities. A particular interest was to explore how serendipity as a by-product of these open online encounters can occur. Data were gathered through an online survey, semi-structured interviews, and online artifacts. The findings suggest the serendipitous nature of content aggregation in a PLE and provide evidence of serendipity as a valuable and unexpected source for learning. [ABSTRACT FROM AUTHOR]

Background Many patients with cancer have multiple symptoms that affect their sense of well-being and this has become an increasingly prominent topic in oncology research. The purpose of this study was to evaluate quality of life (QOL) in Iranian cancer patients undergoing chemotherapy. Methods 118 cancer patients who underwent chemotherapy and who met the inclusion criteria were enrolled in the study. This cross-sectional analytical study included consecutive Iranian patients treated at Qom Chemotherapy Center from January 2012, to June 2013. The participants completed an Iranian version of the brief form of the WHOQOL assessment instrument and a demographic checklist. Data were analysed using SPSS-PC software, descriptive analysis, independent sample t -tests, one-way ANOVA models, Tukey’s post hoc test, and linear regression. Findings The mean age of patients was 52.11 ± 1.57 years. Most were married (84%). 32% were housewives and 27% were unemployed. 36% were uneducated, 53% had an educational level of less than a diploma, and only 8% received academic education. The mean time from cancer diagnosis was 16. 76 ± 2.32 months. As for the site of cancer, the largest proportion had breast cancer (35%), followed by bowel (17%) and lung (10%) cancers. Most patients had a relatively average level of overall QOL. QOL scores were low in older and less educated patients but these scores were not affected by the marital status or type of cancer. No significant regression was observed between duration of disease and treatment and mean QOL scores. Interpretation The results emphasise that older and less educated patients have lower QOL scores. These patients may require a greater level of support and education to improve their QOL. Overall, patients in the present study had a relatively average level of global QOL. [ABSTRACT FROM AUTHOR]