Influence of luminal stenosis in aneurysmal and non-aneurysmal blunt cerebrovascular injury

Background

Current blunt cerebrovascular injury (BCVI) grading grossly differentiates injury characteristics such as luminal stenosis (LS) and aneurysmal disease. The effect of increasing degree of LS beyond the current BCVI grading scale on stroke formation is unknown.

Increased hospital costs are associated with low skeletal muscle mass in patients undergoing elective open aortic surgery

Objective

Low psoas muscle area is shown to be an indicator for worse postoperative outcome in patients undergoing vascular surgical. Additionally, it has been associated with longer durations of hospital stay in patients with cancer who undergo surgery and subsequently greater health care costs in Europe and the United States. We sought to evaluate this effect on hospital expenditure for patients undergoing vascular repair in a health care system with universal access.

The roles of basic psychological needs,self-compassion,and self-efficacy in the development of mastery goals among medical students

Abstract

Aim: Competency-based medical education aims to foster mastery goals in learners. We examined medical students’ mastery approach (beneficial) and mastery avoidance (maladaptive) goals and their associations with students’ basic psychological needs, self-compassion, and self-efficacy.

Methods: This was a cross-sectional study employing an online questionnaire. Two hundred medical students in all four years of the medical program completed the questionnaire, containing measures of mastery goals, basic psychological needs (autonomy, competence, relatedness), self-compassion, and self-efficacy. Regression analyses were performed.

Results: Of the three basic psychological needs, the need for competence was significant in explaining both types of mastery goals. Self-efficacy and self-compassion were significant in explaining mastery approach and mastery avoidance goals, respectively.

Conclusions: Creating learning environments that are supportive of students’ need for competence, raising students’ awareness of the value of learning from mistakes in competency acquisition, and providing opportunities for students to experience self-efficacy may foster beneficial mastery approach goals in medical students.     

Ultrasound-Assist Extrusion Methods for the Fabrication of Polymer Nanocomposites Based on Polypropylene/Multi-Wall Carbon Nanotubes

Isotactic polypropylenes (iPP) with different melt flow indexes (MFI) were used to fabricate nanocomposites (NCs) with 10 wt % loadings of multi-wall carbon nanotubes (MWCNTs) using ultrasound-assisted extrusion methods to determine their effect on the morphology, melt flow, and electrical properties of the NCs. Three different types of iPPs were used with MFIs of 2.5, 34 and 1200 g/10 min. Four different NC fabrication methods based on melt extrusion were used. In the first method melt extrusion fabrication without ultrasound assistance was used. In the second and third methods, an ultrasound probe attached to a hot chamber located at the exit of the die was used to subject the sample to fixed frequency and variable frequency, respectively. The fourth method is similar to the first method, with the difference being that the carbon nanotubes were treated in a fluidized air-bed with an ultrasound probe before being used in the fabrication of the NCs with no ultrasound assistance during extrusion. The samples were characterized by MFI, Optical microscopy (OM), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), electrical surface resistivity, and electric charge. MFI decreases in all cases with addition of MWCNTs with the largest decrease observed for samples with the highest MFI. The surface resistivity, which ranged from 10¹³ to 10⁵ Ω/sq, and electric charge, were observed to depend on the ultrasound-assisted fabrication method as well as on the melt flow index of the iPP. A relationship between agglomerate size and area ratio with electric charge was found. Several trends in the overall data were identified and are discussed in terms of MFI and the different fabrication methods.