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Background: Feedback‐based learning (FBL) focuses on guiding the learning process according to educational objectives and the student's needs. This study aimed to investigate surgical nursing students' perceptions and explore their experiences of FBL. Method: The present study used a mixed‐methods sequential explanatory design that was conducted in the quantitative and qualitative phases. Surgical nursing students participated in the quantitative phase (n = 105). In the first phase, students completed two questionnaires about FBL and clinical feedback. Semi‐structured face‐to‐face interviews were used to collect qualitative data in the second phase. Graneheim and Lundman's inductive approaches were used to analyse the qualitative data. Results: The mean (SD) score for students' perception of FBL was 3.99 ± 0.70. The qualitative results were explored in two themes, "motivational support for improvement" and "unpleasant learning". Conclusion: In this study, the positive and negative aspects of FBL were explained. FBL is perceived as a motivational support mechanism to improve students' capabilities during their academic courses and also prepare them for future careers. Conversely, FBL may experience unpleasant learning due to negative feedback and negative emotions. [ABSTRACT FROM AUTHOR]

Background: Feedback is a critical component of education but may not always be delivered in a useful manner. This study assessed surgical nursing students' perception of the feedback they received on a clinical rotation. Methods: This is a sequential mixed-method study. The first stage surveyed surgical nursing students in surgical units about the feedback they received. In the second stage, participants' experiences receiving feedback were explored in interviews, and analyzed by a conventional content analysis approach. Results: The majority of nurses found that feedback was not helpful, citing a lack of constructive feedback. Negative feedback was often delivered in a public setting. Comments were frequently based on secondary information rather than direct observation. Discussion: Feedback to nurses on the surgical unit is not perceived by students as constructive. Clinical teachers did not appear to be aware of the educational effect of the feedback on the learning process of students. In addition, the setting for feedback often undermined its effectiveness. Staff development on effective feedback for teachers on the surgical unit is recommended. [ABSTRACT FROM AUTHOR]

Background: Extracellular vesicles (EVs) may accelerate cell death during the course of infection. Mycobacteria could invade the host's immune system and survive in the host by modulation of miRNAs. MiRNAs' differential expressions can serve as biomarkers. This study evaluates THP-1 monocyte cell death by EVs from serum of patients with mycobacteria and assesses serumderived exosomal miRNAs to increase or decrease THP-1 monocyte cell death. Materials and Methods: EVs were purified from serum of patients with mycobacteria and cultured with THP-1 monocyte. The cell death was determined via annexin V-FITC and PI staining. The microRNA was isolated from serum-derived EVs of the patients. Expression level of Hsa-miR-20a-5p, Hsa-miR-29a, Hsa-miR-let7e, and Hsa-miR-155 was assessed using qRT-PCR. Results: Cell death was accelerated in 10 and 5 µg/ml concentrations of the EVs (p<0.05). Minimum cell death was seen in 2.5 and 1.2 µg/ml concentrations (p<0.05). In tuberculosis (TB) patients, expression of miR-20a-5p, miR-29a, and miR-let7e were significantly enhanced (p=0.0001), but miR-155 expression reduced. ROC analysis showed diagnostic biomarkers of miRNAs with an AUC=0.6933 for miR-20, AUC=0.6011 for miR-29a, AUC=0.7322 for miR-let7e, and AUC=0.7456 for miR-155 for active tuberculosis. Expression of miR-let7e, 20a, and 29a in M. avium vs. M. tuberculosis was overexpressed (P=0.01, P=0.0001, and P=0.0001, respectively). Also miRs let7e and 20a expression was accelerated in M. abscessus vs. M. tuberculosis (P=0.0001 and P=0.002, respectively). Conclusion: EVs accelerates cell death and may not be ideally considered for drug delivery and vaccine developments. Circulating exosomal microRNA MiR-20, miR-let7e, and miR-155 facilitate development of potential biomarkers of pulmonary tuberculosis and non-tuberculosis. [ABSTRACT FROM AUTHOR]

The effects of incorporating hyperbranched polymers (HBPs) and different nanoclays [Cloisite ® 30B and halloysite nanotubes (HNT)] on the mechanical, morphological, and thermal properties of solid and microcellular poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) were investigated. According to the X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses, Cloisite 30B exhibited a combination of exfoliation and heterogeneous intercalation structure for both solid and microcellular PHBV-12% HBP-2% Cloisite 30B nanocomposites. TEM images indicated that HNTs were uniformly dispersed throughout the PHBV matrix. The addition of 2% nanoclays improved the thermal stability of the resulting nanocomposites. The addition of HBP+poly(maleic anhydride-a/t-1-octa-decene) (PA), Cloisite 30B, and HNT reduced the average cell size and increased the cell density of the microcellular components. The addition of (HBP+PA), Cloisite 30B, and HNT also increased the degree of crystallinity for both solid and microcellular components in comparison with neat PHBV. Also, with the addition of 12% (HBP+PA), the area under the tan - δ curve, specific toughness, and strain-at-break of the PHBV-HBP nano-composite increased significantly for both solid and microcellular specimens, whereas the storage modulus, specific Young's modulus, and specific tensile strength decreased. The addition of 2% nanoclays into the PHBV-HBP nanocomposites improved the storage modulus, specific Young's modulus, and specific tensile strength of the PHBV-HBP-nanoclay-based nanocomposites, but they were still lower than those of the neat PHBV. POLYM. ENG-SCI., 51:1815-1826, 2011. © 2011 Society of Plastics Engineers, INTRODUCTION Broadening the use of biobased and biodegradable polymers such as poly(hydroxyalkanoates) (PHA) can reduce our dependence on petroleum-based polymers, which can have an adverse impact on the environment [1-3]. [...]

Poly(ethylene terephthalate) (PET) resin is one of the most widely used thermoplastics, especially in packaging. Because thermal and hydrolytic degradations, recycled PET (RPET) exhibits poor mechanical properties and lacks moldability. The effects of adding elastomeric modifiers, chain extenders (CE), and poly(butylene adipate-co-terephthalate), PBAT, as a toughener to RPET on its moldability and mechanical property were investigated. Melt blending of RPET with CE, thermoplastic elastomer (TPE), and/or PBAT was performed in a thermokinetic mixer (K-mixer). The blended materials were then injection molded to produce tensile specimens. Various techniques were used to study the mechanical properties, rheological properties, compatibility, and crystallization behavior of the RPET blends. By melt blending with proper additives, recycled PET regained its moldability, thereby enabling the recycling of RPET. Furthermore, the addition of CE greatly enhanced the mechanical properties of RPET. While the RPET and TPE blends also showed improved mechanical properties, the improvement was less significant and the blends were often immiscible due to the difference in polarities between RPET and TPE. Finally, it was found that the mechanical properties of RPET blends depended on the prior thermal history of the material and could be improved with an extra annealing step that increased the degree of crystallinity. POLYM. ENG. SCI., 51:1023-1032, 2011. [C] 2011 Society of Plastics Engineers, INTRODUCTION Poly(ethylene terephthalate) (PET) is one of the most widely used thermoplastic polyesters. PET is extensively used in various applications, such as beverage bottles, fibers, moldings, and sheets because of [...]

Solid and microcellular specimens made of poly (3-hydroxybutyrate-co-3-hydroxyvalerate)(PHBV)/poly(butylene adipate-co-terephthalate) (PBAT) blends with three different weight ratios (i.e., PHBV/PBAT = 98.5/1.5 (Y1000P), 45/55 (5010P), and 30/70 (6010P), respectively) were prepared via conventional and microcellular injection molding process, respectively. Various properties such as miscibility, cell morphology, thermal, and mechanical properties were investigated. Compared with the microcellular specimens, the solid specimens showed better miscibility. Increasing the PBAT content led to higher specific toughness and strain-at-break, but lower specific modulus and specific strength for both solid and microcellular specimens. In addition, increasing the PBAT content increased the average cell size, but decreased the cell density of the microcellular samples. Finally, the crystallinity of PHBV in the PHBV/PBAT blends decreased significantly with increasing PBAT content for both solid and microcellular specimens. POLYM. ENG. SCI., 50:1440-1448, 2010. [C] 2010 Society of Plastics Engineers, INTRODUCTION Biobased plastics have gained significant interest in recent years. Compared with petroleum-based synthetic polymers, biobased polymers made from renewable resources such as plants and crops can be naturally recycled [...]

Water is one of the important parameters in flotation and represents 80-85% of the volume of mineral pulp processed in flotation circuits. In our recent studies revealed was found that sulphide minerals generated H2O2 in pulp liquid during wet grinding and also the solids when placed in water immediately after dry grinding but the effect of type of water on the oxidation of pulp components and hence in deteriorating the concentrate grade and recovery in flotation has not been explored yet. In this study, the effect of two types of water on the formation of H2O2 as an oxidizing agent stronger than oxygen was investigated. process water is water that is used for a flotation process in Bama Company. It was shown that process water generated 482 μM H2O2 but deionized water generated 16 μM. The result shows the recovery of chalcopyrite in pH 6 is 60% and 40% in process water and deionized water respectively. Also, recovery of galena in pH 6 is 30% and 20% in process water and deionized water respectively. [ABSTRACT FROM AUTHOR]