Passive Maple-seed Robotic Fliers for Education, Research and Entrepreneurship

As inspirations from flora and fauna have led to many advances in modern technology, the concept of drawing ideas from nature for design should be reflected in engineering education. This paper focuses on a maple-seed robotic flier (MRF) with various complexities, a robotic platform modeled after the samaras of maple or ash trees, to teach STEM concepts to K-12 learners. Experiments using MRFs were also designed and incorporated into an undergraduate engineering course. Details are given on how the MRFs have been incorporated into K-12 camps and the undergraduate course. Unique features of MRF development are (a) very simple (using LEGOs and paper) to extremely complex (incorporation of microcontrollers and sensors) learning suitable for pre-K children, free-will adult learners, workforce training, undergraduate and graduate students, (b) research-oriented education, (c) entrepreneurship education and (d) trans-disciplinary education and research. Using microfabrication and nanofabrication technologies, the long range goal is to mass produce MRFs for surveillance in hard-to-reach and dangerous environments

UNRWA and a durable solution for Palestinian refugees : a comparative study

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Mathematical modelling of complex host-parasite interactions under global climate change

Mathematical modelling in microbiology, especially simulating bacteria-phage interactions, has been a subject of extensive research. However, despite numerous previous publications, several fundamental questions regarding modelling this complex system remain unanswered. In particular, a key question is about the role of spatial heterogeneity of the environment in the dynamics of bacteria and phages, as well as their interactions. Another challenge is our current lack of understanding of how external forcing of the system, due to daily, seasonal, or global trends (climate change) would influence the long-term behaviour and prediction of the model. This thesis focuses on the mathematical modelling of host-parasite interactions under global climate change and its implications for Melioidosis, a significant infectious disease caused by the environmental bacterium B. pseudomallei, which is prevalent in Southeast Asia and Northern Australia. We utilized mathematical modelling to predict dangerous timings and locations, particularly for agricultural workers. We collected temperature and UV index data and projected future trends using SARIMA and trigonometric models. Our projections indicate a slightly greater annual temperature increase than previous studies. We then analyzed the probability of controlling bacterial populations by phages using a model and historical data from high-risk provinces. Seasonal variations in population dynamics were observed, influenced by temperature and UV radiation. The density of susceptible bacteria was highest in the evening, warmer months, and correlated with temperature. We also studied spatiotemporal dynamics in the upper layer of soil using an extended temperature-dependent lysogeny model. Lysogenic bacteria dominated the upper soil layers, while lytic bacteria were found near the surface. Soil mixing and excessive use of fertilizers were found to impact bacterial and phage densities, highlighting the need for revising the existing agricultural practices. Furthermore, the study emphasized the role of pesticides and environmental factors in bacteria-phage interactions. Understanding these dynamics is crucial for predicting disease spread and implementing preventive measures. Our findings provide insights into the effects of climate change and agricultural practices on Melioidosis dynamics, emphasizing the need to consider environmental factors in future studies.</p

Mineral trioxide aggregate apexogenesis: A systematic review

Objectives: To evaluate the clinical and radiographic outcomes of apexogenesis with mineral trioxide aggregate (MTA) against other pulpotomy agents in carious/traumatized immature permanent teeth. Data Source: A web-based search for possibly relevant scientific papers in the English language between January 2013 and August 2022 was undertaken in the databases such as PubMed, Scopus, Cochrane Library, and EMBASE. Only randomized clinical trials that compared MTA against other pulpotomy medicaments conducted in vital immature permanent dentition with open apex, having a sample size of not less than 20 with at least 6 months follow-up, reporting clinical or radiographic outcomes were included in the current review. Case studies, case series, animal studies, in vitro studies, non-clinical/clinical trials on mature/necrotic permanent or primary dentition, systematic reviews, and letters to the editor were excluded. Study Selection: A total of 236 articles were retrieved from the databases during the search procedure. Two independent investigators conducted a full-text review of 83 studies following a screening of titles and abstracts. Eventually, seven studies were considered for the review. The Cochrane bias assessment tool was used to evaluate the quality of included studies. Five of the selected studies were assigned a low evidence level, whereas two were rated a high evidence level. Conclusion: The present review indicated that the diverse pulpotomy agents had comparable clinical outcomes with MTA for apexogenesis in traumatized or carious immature permanent teeth. However, there is a lack of substantial information to draw firm conclusions about the benefits of one material over another

Pharmacological and toxicological investigations on foeniculum vulgare dried fruit extract in experimental animals

The ethanol extract of the dried ripe fruit of Foeniculum vulgare (500 mg/kg) was tested for diuretic, analgesic, antipyretic, antimicrobial, cytotoxic activities and its effect on bile secretion in rats. Also, the acute toxicity after 0.5, 1 and 3 gkg was investigated in mice. The extract showed diuretic, analgesic, antipyretic activities and it enhanced bile secretion. As an antimicrobial agent, the extract inhibited the growth of Staphylococcus aweus and Bacillus subtilis and showed a marked mitodepressive effect. At a dose of 3 fig, it caused piloerection and it depressed locomotor activity but caused no deaths when administered acutely to mice.This work was performed in the College of Pharmacy, King Saud University, Riyadh-Saudi Arabia and was funded by a grant from King Abdulaziz City for Science and Technology

Performance investigation of organic Rankine-vapor compression refrigeration integrated system activated by renewable energy

In this article, the performance and working fluid selection for an organic Rankine cycle-vapor compression refrigeration (ORC–VCR) integrated system activated by renewable energy is investigated. The performance of the system is described by the system coefficient of performance (COPS), and the refrigerant mass flow rate per kilowatt refrigeration capacity ( m˙total m ˙ total ). Twenty-three pure substances are proposed as working fluids for the integrated system. The basic integrated system performance is assessed and compared using the proposed working fluids. The basic VCR cycle works between 35 and 0 °C, while the basic ORC works between 35 and 100 °C. The impacts of different operating parameters such as the evaporator, the boiler, and the condenser temperatures on the ORC–VCR system performance are also examined. The results show that the cyclopentane accomplished the highest system performance under all investigated operating conditions. Accordingly, among the examined 23 working fluids, cyclopentane is the most appropriate working fluid for the integrated system from the viewpoints of environmental concerns and system performance. Nevertheless, due to its high flammability, further restrictions should be taken. The basic integrated system COPS, refrigeration effect, and the corresponding m˙total m ˙ total utilizing cyclopentane are 0.654, 361.3 kW, and 0.596 × 10−2 kg/(s kW), respectively