57 research outputs found

    Flash sintering of zirconia/alumina powders

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    Yttria-stabilized cubic zirconia (YSZ) is the most-common electrolyte material for solid oxide fuel cells due to its reasonable oxygen-ion conductivity and chemical stability. To achieve suitable ionic conductivities, YSZ ceramics must be near theoretical density, requiring sintering temperatures around 1450°C. In 2011, it was demonstrated that flash sintering densifies YSZ in a few seconds at 750°C.1 During flash sintering, an electric field is applied across the sample and at a certain threshold temperature, the sample conductivity and power dissipation rapidly increase causing densification. Since densification occurs in just a few seconds, grain growth can be difficult to control. During conventional sintering of YSZ ceramics, researchers have demonstrated that the addition of a small quantity of aluminum oxide (Al2O3) pins grain boundaries, reducing YSZ grain size.2 However, the effect of small quantities of Al2O3 addition on the grain growth of flash sintered YSZ has not been studied. Please click Additional Files below to see the full abstract

    Feasibility of a mHealth Approach to Nutrition Counseling in an Appalachian State

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    Abstract: West Virginia is a rural state with an aging population that may experience barriers to accessing nutritional and lifestyle counseling. This study examined feasibility of an online personalized nutrition tracking application, Good Measures (GM), with patients at seven health care clinics throughout the state. Fourteen healthcare providers and 64 patients 18 years or older with a Body Mass Index (BMI) greater than or equal to 30 and access to the Internet were recruited for this 12-week feasibility study. Patient participants logged meals and exercise into the GM application via smart phone, tablet, or computer and virtually engaged with a Registered Dietitian Nutritionist (RDN) in one-on-one sessions. The primary endpoint was to examine feasibility of the program by usage of the application and feedback questions regarding the benefits and challenges of the application. Participants were predominately white (92%) and female (76%). Minimal improvements in weight and systolic blood pressure were found. Participant attitude survey data declined from 4-weeks to 12-weeks of the intervention. Interestingly though, patients in a rural clinic had lesser declines in attitudes than peri-urban participants. Qualitative feedback data identified participants predominately had a positive overall feeling toward the approach. Participants expressed favorability of RDN access, the variety of foods, but did give suggestions for in-person meetings and more updating of the application. Implementing a technology approach to nutrition in rural areas of West Virginia using a mobile application with RDN access may be one strategy to address public health issues such as obesity

    HP1-β is required for development of the cerebral neocortex and neuromuscular junctions

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    HP1 proteins are thought to be modulators of chromatin organization in all mammals, yet their exact physiological function remains unknown. In a first attempt to elucidate the function of these proteins in vivo, we disrupted the murine Cbx1 gene, which encodes the HP1-β isotype, and show that the Cbx1−/−-null mutation leads to perinatal lethality. The newborn mice succumbed to acute respiratory failure, whose likely cause is the defective development of neuromuscular junctions within the endplate of the diaphragm. We also observe aberrant cerebral cortex development in Cbx1−/− mutant brains, which have reduced proliferation of neuronal precursors, widespread cell death, and edema. In vitro cultures of neurospheres from Cbx1−/− mutant brains reveal a dramatic genomic instability. Our results demonstrate that HP1 proteins are not functionally redundant and that they are likely to regulate lineage-specific changes in heterochromatin organization

    Integrated Seismic Reservoir Characterization and Modeling: A Gulf of Mexico 3D Case History

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    Poly(oxazolines)

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    The effectiveness of e-learning in focused cardiac ultrasound training: a prospective controlled study

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    Abstract Introduction Focused Cardiac Ultrasound (FOCUS) is an essential tool for rapid cardiac assessment across various clinical subspecialties. Consequently, teaching foundational FOCUS skills is of critical importance. This study investigates the effectiveness of e-learning in imparting FOCUS skills. Materials and methods This prospective, controlled study assessed competency development among medical students attending a FOCUS workshop (study group) at two time points: T1 (pre-training) and T2 (post-training, after completing e-learning). The competence gain of the group was compared to a reference group (control group) of physicians who had also used the e-learning in preparation for a certified FOCUS workshop. Objective competencies were measured at both time points using short-answer and multiple-choice theory tests. Subjective self-assessments of competencies and opinions of the e-learning were investigated through evaluation forms at T2 using a 7-point Likert scale (1 = strongly disagree, 7 = strongly agree). Demographic information was collected at T1, and user behaviour during e-learning was assessed at T2. Primary endpoints were the increase in theoretical competencies (study group) and the comparison of subjective and objective competency levels (study vs. reference). Results A total of 104 participants (study group = 48; reference group = 56) were included. The study group exhibited a significant (p < 0.001) increase in theoretical competencies. However, at T2 the reference group achieved significantly higher theoretical test scores (p < 0.001). One influencing factor was previous practical experience (p = 0.02), which was significantly higher in the reference group (p < 0.001). Both groups estimated their competency at the end of preparation to be at similar levels (4.3 ± 0.9 scalepoints [SP] versus 4.3 ± 1.0 SP; p = 0.94). Evaluation results of the e-learning were positive in both groups (5.8 ± 0.9 SP versus 6.2 ± 0.7 SP; p = 0.04), with results in the reference group being significantly higher. Conclusion Both the improvement in competencies and the positive reception of digital learning media should encourage the increased implementation of e-learning formats. This study shows that such formats in ultrasound training can effectively complement face-to-face workshops and should be included in certified training curricula

    The Effectiveness of Digital vs. Analogue Teaching Resources in a Flipped Classroom for Undergraduate Focus Cardiac Ultrasound Training: A Prospective, Randomised, Controlled Single-Centre Study

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    Introduction: This study investigated the effectiveness of e-learning compared to traditional teaching methods in ultrasound education, centring on a focus cardiac ultrasound (FoCUS) course for third-year undergraduate medical students. With the rise of digital teaching methods, it is essential to evaluate their impact on the development of theoretical and practical skills in ultrasound training. Methods: A prospective, randomised, controlled trial was conducted involving two groups of students participating in a one-day FoCUS course delivered in a flipped classroom format. The study group used e-learning resources, while the control group used hard-copy lecture notes. Assessments were conducted at three stages: before the course, during the preparation phase, and after the course. Evaluations included self-assessment surveys, theory tests, and practical exams using direct observation of procedural skills (DOPS) tests. The study group had 15% less practice time compared to the control group. Results: A total of 109 complete datasets (study group, n = 52; control group, n = 57) were analysed. Both groups showed an equivalent initial level of and a continuous and significant (p &lt; 0.01) increase in subjective and objective skills over the evaluated time frame. The study group achieved significantly (p = 0.03) higher results in DOPS (T2) than the control group. No significant differences were found in the total scores of the theory tests (T2 + T3) or DOPS (T3). Both groups rated their teaching materials, motivation, and the course concept in similarly high scale ranges. Conclusions: The findings suggest that e-learning is as effective as traditional methods in developing ultrasound skills and may serve as a viable alternative, even with reduced face-to-face interaction. These results indicate that accreditation processes could be applied similarly to those for traditional formats without requiring in-person training as a prerequisite for qualit
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