α-Helical Peptides on Plasma-Treated Polymers Promote Ciliation of Airway Epithelial Cells

Airway respiratory epithelium forms a physical barrier through intercellular tight junctions, which prevents debris from passing through to the internal environment while ciliated epithelial cells expel particulate-trapping mucus up the airway. Polymeric solutions to loss of airway structure and integrity have been unable to fully restore functional epithelium. We hypothesized that plasma treatment of polymers would permit adsorption of α-helical peptides and that this would promote functional differentiation of airway epithelial cells. Five candidate plasma compositions are compared; Air, N2, H2, H2:N2 and Air:N2. X-ray photoelectron spectroscopy shows changes in at% N and C 1s peaks after plasma treatment while electron microscopy indicates successful adsorption of hydrogelating self-assembling fibres (hSAF) on all samples. Subsequently, adsorbed hSAFs support human nasal epithelial cell attachment and proliferation and induce differentiation at an air-liquid interface. Transepithelial measurements show that the cells form tight junctions and produce cilia beating at the normal expected frequency of 10-11 Hz after 28 days in culture. The synthetic peptide system described in this study offers potential superiority as an epithelial regeneration substrate over present “gold-standard” materials, such as collagen, as they are controllable and can be chemically functionalised to support a variety of in vivo environments. Using the hSAF peptides described here in combination with plasma-treated polymeric surfaces could offer a way of improving the functionality and integration of implantable polymers for aerodigestive tract reconstruction and regeneration

Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700

Search for gravitational waves associated with gamma-ray bursts detected by Fermi and Swift during the LIGO–Virgo run O3b

We search for gravitational-wave signals associated with gamma-ray bursts (GRBs) detected by the Fermi and Swift satellites during the second half of the third observing run of Advanced LIGO and Advanced Virgo (2019 November 1 15:00 UTC–2020 March 27 17:00 UTC). We conduct two independent searches: a generic gravitational-wave transients search to analyze 86 GRBs and an analysis to target binary mergers with at least one neutron star as short GRB progenitors for 17 events. We find no significant evidence for gravitational-wave signals associated with any of these GRBs. A weighted binomial test of the combined results finds no evidence for subthreshold gravitational-wave signals associated with this GRB ensemble either. We use several source types and signal morphologies during the searches, resulting in lower bounds on the estimated distance to each GRB. Finally, we constrain the population of low-luminosity short GRBs using results from the first to the third observing runs of Advanced LIGO and Advanced Virgo. The resulting population is in accordance with the local binary neutron star merger rate

A Programmable-Logic Based Multiprocessor Engine for Real-Time Vision Preprocessing

: Real-time vision is central to many embedded applications (e.g. vehicle guidance). It is a computationally intensive task well beyond current general purpose computing platforms such as PCs and workstations. Thus, most real time vision systems need special high performance computing platforms, commonly provided in the form of parallel processing engines or dedicated hardware. It is well known that dedicated hardware has the potential to provide the fastest execution speeds but its rigidity often deters potential users. They prefer the economies of scale and flexibility which programmable systems offer. The proposed architecture uses new generations of re-programmable logic devices and modularised hardware, thereby gaining the performance advantage of hard-wired logic with the flexibility and associated economies of programmable systems. The architecture takes the form of an extensible processing hierarchy consisting of a set of tightly coupled parallel processors, each processing a ..

Discovery: Differential Student Impact is Evident Within an Inquiry-focused Secondary/Post-secondary Collaborative STEM Program

© 2020 American Society for Engineering EducationIntroduction: Curriculum for high school students who participate in a science, technology, engineering, and math (STEM) are generally focused on delivery of knowledge in effort to ensure achievement of learning outcomes related to important scientific concepts in preparation for post-secondary study. Considering a global learning environment of rapid technological change at the cutting edge, curriculum STEM knowledge quickly loses its relevance to application, highlighting the importance in focusing on development of a critical thinking framework for students. In 2016, graduate students at Institution X created Discovery, a collaborative educational program focused on developing and reinforcing critical thinking skills of high school students through inquiry in the context of biomedical engineering (BME) in a post-secondary setting. Evaluation of student performance has revealed the value of this a differential learning environment for students who struggle in a knowledge-focused classroom. Following five terms of activity, the program has recently grown to include participation of a second school from a different socioeconomic region, allowing for assessment of cultural impact of learning. Methods: To date, Discovery has included engagement each term of approximately 25 post-secondary student instructors and 2 faculty members, and has impacted approximately 200 senior science students (Grades 11 & 12; biology, chemistry and physics classes) and 9 STEM educators from two local secondary schools. Graduate student leaders and high school educators collaboratively developed hands-on BME-based practical challenges aligning with school science curricula (new ideation each term), executed by small groups of high school students in capstone format to address course-specific requests for proposals. Entire class cohorts from each school visited campus on different days throughout the term, executing the same project and sharing outcomes at a culminating symposium attended by both schools. To validate student learning in the context of high school curriculum, educators assigned 15% of term course grades to Discovery deliverables. Surveys were administered pre- and post-participation to garner insight into student perceptions of the experience. Student attendance was monitored and grades for on-campus program deliverables were compared to grades for remaining classroom deliverables. Results and Discussion: Combinational assessment of five terms of data from the inaugural participating high school demonstrated positive impact of this inquiry focused differential learning environment. Notably, a cohort of students with reduced success in the knowledge-focused classroom environment excelled during Discovery, displaying average program grades >15% higher than their overall course term average. This suggests the value of Discovery as a learning environment that inspires STEM participation. Program expansion in Spring 2019 saw the addition of a second school, doubling student and instructional participation. Preliminary assessment of one term of multi-school participation presents very different student outcomes, with notably less engagement observed by educators and program instructors in the inquiry-focused program structure. This suggests a potential cultural element to program impact, wherein the socioeconomics of the newest school is higher and educators remarked student attitudes toward more ambiguous learning is resistive. At ASEE 2020, we will expand on our findings to include longitudinal data reflecting variation in student success between these two school cohorts. Conclusions: To date, student and educator engagement and enthusiasm reinforce that Discovery provides a platform to blur the divide between secondary and post-secondary learning, fostering the development of critical thinking skills crucial for the success of future STEM generations. Our current findings suggest a cultural impact to this success, presenting opportunities to tune program structure to meet individual student needs. We anticipate continued positive impact of this program on high school science students this term, regardless of school of origin or previous participation.This program is financially supported by the IBBME and the NSERC PromoScience program(PROSC 515876-2017)