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Final Design Report, Team 12: The Rad Finders
Get PDFThe Rad Finder team was tasked with developing an array of detectors that could locate the position of a radioactive gamma-ray source in three dimensions. Since the strength of the source was to be unknown, standard triangulation algorithms would not work. Thus, the team had to develop a method of triangulation that, to the team’s knowledge, had never been done before. This project was sponsored by Los Alamos National Laboratory (LANL) and overseen by Dr. Bahram Nassersharif from the University of Rhode Island. The detection array, the “RADFINDER”, consisted of three gamma-ray detector wands attached to three subsequent analyzers from which the readings were gathered. Each detector wand was then mounted on its respective tripod. Ergonomic tripod adapters for these wands were designed in AutoCAD and manufactured using 3D printers. Additionally, it was vital to the triangulation algorithm that the exact positions of each detector wand were known. A Leica DISTO measuring device was thus implemented to determine the exact position of each detector wand. For the DISTO’s laser to gather accurate data, targets that were to be placed around each wands’ crystals were designed and 3D printed.
The triangulation algorithm constructed by the team was initially constructed in Mathematica, but later moved to MATLAB. The functionality of MATLAB allowed for a GUI to be constructed, as well as a three-dimensional plot displaying the positions of each detector wand and the calculated source position. The algorithm consisted of a system of three spherical equations, one for each detector. The system was then solved, and the result was two sets of x, y, and z coordinates. One of these sets was a phantom point that could be eliminated using logic. However, to improve the consistency of the array, a method of mathematically eliminating the phantom point was developed and implemented. This involved gathering a fourth detector point and solving an additional system of equations. The results could then be compared and the two source points closest to one another was where the source position was calculated to be.
Using the array and triangulation software that was constructed, the team utilized the Rhode Island Nuclear Science Center (RINSC) to conduct testing of the accuracy of the RADFINDER. The RINSC provided the team with gamma-ray emitting sources of varying strengths. For each source, the team tested to find the maximum range at which the detectors could be from the source before the readings were less than 150% of the background radiation. Once this distance was found, the target volume could be calculated for. The detectors were then placed at the corners of the target volume and shot with the DISTO device to find each wand’s position. The radioactive source was then placed randomly in the target volume and shot with the DISTO device to find its true position. Readings were then gathered off the analyzers in counts per second (cps) for 60 seconds and averaged. The readings off the detectors and the position of the detectors were then entered into the MATLAB analysis program, which calculated the position of the source in three dimensions. Through all the team’s trials, the calculated source position was always within +/- 10% of the target volume, which satisfied one of the team’s design specifications. Additionally, no team member picked up a measurable dose, which also satisfied the team’s specification for ALARA (maintaining radiation doses as low as reasonably achievable).
The RADFINDER was designed to prove concepts that are integral to the team’s final design goal. If scaled up, the RADFINDER could have real-world applications in nuclear non-proliferation and the detection of orphan sources
Variable Ballasting Systems
Get PDFThis report describes the overall design procedure to compose a ballasting system for various Autonomous Underwater Vehicles (AUVs) sponsored by Raytheon Technologies. Common AUV systems are used for a wide range of applications from environmental monitoring, oceanic exploration, to data collection. AUVs also have many technical advantages that make underwater tasks more efficient, cost-effective, and generally safer. Raytheon Technology, specifically, is looking to improve their existing ballasting mechanism for their AUVs to use for military defense. For this project, Raytheon Technology has set a standard for this design to improve upon current space, weight, and power efficiencies. The end goal of this design is to create a modular ballasting system, to meet the specification requirements set by Raytheon, to be designed for a Type B AUV.
Ballasting systems are known to drive the vertical motion of AUV systems based on density control. To control the desired depth of such devices, ballast is used to create negative, neutral, or positive buoyancy based on Archimedes Principle. Throughout the semester the team was able to research, collaborate, and design 120 concepts for potential ballasting systems. After utilizing the engineering and scientific method these concepts were evaluated using various analysis procedures. The determination process included the assessment of the designs through multiple Pugh analysis and Gantt charts and mentor advice. Each concept had to be met with the design specifications set by Raytheon. Predominantly, the vehicle should be able to remove .6lbs of water and reach a depth of 14ft, having a variable ballasting time no longer than 10 minutes. Conclusively, the expected mission length for this system is to be at least 30 minutes.
Over the course of the semester, a syringe-type ballast system design was established to meet the desired criteria. To establish proof of this concept, a total of 500 budget and is expected to increase as more improvements are to be made. Furthermore, the weight of the current system using a linear actuator and plastic syringe is under 3lbs; however, this weight is also expected to decrease in the next few months. The work of the previous five-month period is logged in this report as are future project aspirations. Continuously, a financial and market analysis was done to evaluate the overall cost of this project and industry. The goal of next semester is to optimize the efficiency of the control system through multiple ballast tests to finalize this product
Effects of Radiation Dose on Material Properties
Get PDFConducting experiments is a vital process for any progression. Nuclear science is a complex subject that still requires immense research. With progression in this field there are many technological advancements that are possible. Our student design team has the unique opportunity to help make this process more efficient for the employees at the RINSC.
In collaboration with the RINSC and General Dynamics Electric Boat, our student capstone team will design and implement a machine to make testing more efficient. As of now the RINSC has a tedious process to test the effects of gamma radiation on samples. The reactor pool has an irradiation tube that extends to the bottom of the tank. Samples spend a variety of time at various depths to measure the effects of gamma radiation. To do this the samples are lowered by hand into the tube via a small aluminum container. The cotton rope is then tied in place and the sample is timed by stop watch. When testing is complete the samples are then pulled out. Our design team plans to automate most of this process and make testing more efficient.
We attached our final design to the rail on the edge of the pool by C-clamp. Our team proposes that our design will allow the ability to test up to three samples at a time. We expect to make this process seamless for anyone conducting experiments. A scroll wheel will help lower and rise the samples to the desirable depth. If certain samples need to be taken out at varying times, clips will link the cups together for easy removal. There will also be a wire that runs along the rope to directly monitor the sample degradation.
This report highlights our completion of the processes for this design. We have conducted extensive research on related patents and the reaction gamma radiation may have on our materials. Our team created a list of concepts that could possibly improve the testing process. We then compared those topics to the design specifications and narrowed down our selection. The final design is a result of this elimination. After having a concrete idea of what we wanted to accomplish the team then put together a purchase order well under budget. Finally having the needed materials we were able to finish the building
Generation and Computational Characterization of a Complex Staphylococcus aureus Lipid Bilayer
Get PDFStudies indicate a crucial cell membrane role in the antibiotic resistance of Staphylococcus aureus. To simulate its membrane structure and dynamics, a complex molecular-scale computational representation of the S. aureus lipid bilayer was developed. Phospholipid types and their amounts were optimized by reverse Monte Carlo to represent characterization data from the literature, leading to 19 different phospholipid types that combine three headgroups [phosphatidylglycerol, lysyl-phosphatidylglycerol (LPG), and cardiolipin] and 10 tails, including iso- and anteiso-branched saturated chains. The averaged lipid bilayer thickness was 36.7 Å, and area per headgroup was 67.8 Å2. Phosphorus and nitrogen density profiles showed that LPG headgroups tended to be bent and oriented more parallel to the bilayer plane. The water density profile showed that small amounts reached the membrane center. Carbon density profiles indicated hydrophobic interactions for all lipids in the middle of the bilayer. Bond vector order parameters along each tail demonstrated different C–H ordering even within distinct lipids of the same type; however, all tails followed similar trends in average order parameter. These complex simulations further revealed bilayer insights beyond those attainable with monodisperse, unbranched lipids. Longer tails often extended into the opposite leaflet. Carbon at and beyond a branch showed significantly decreased ordering compared to carbon in unbranched tails; this feature arose in every branched lipid. Diverse tail lengths distributed these disordered methyl groups throughout the middle third of the bilayer. Distributions in mobility and ordering reveal diverse properties that cannot be obtained with monodisperse lipids
A Decade of Time Series Sampling Reveals Thermal Variation and Shifts in Pseudo-nitzschia Species Composition That Contribute to Harmful Algal Blooms in an Eastern US Estuary
Get PDFIn 2016-17, shellfish harvesting closed for the first time in Narragansett Bay, Rhode Island, USA, from domoic acid (DA), a neurotoxin produced by diatoms of the Pseudo-nitzschiagenus. Pseudo-nitzschia have occurred frequently for over 60 years in Narragansett Bay’s Long-Term Plankton Time Series (NBPTS), therefore it is surprising that the first closure only recently occurred. Pseudo-nitzschia species are known to vary in their toxin production, thus species identification is critical for understanding the underlying ecological causes of these harmful algal blooms (HABs). DNA in plankton biomass can be preserved for many years, so molecular barcoding of archived samples is useful for delineation of taxa over time. This study used amplification of the Pseudo-nitzschia-specific 18S-5.8S rDNA internal transcribed spacer region 1 (ITS1) in plankton samples and high throughput sequencing to characterize Pseudo-nitzschia species composition over a decade in Narragansett Bay, including eight years before the 2016-17 closures and two years following. This metabarcoding method can discriminate nearly all known Pseudo-nitzschia species. Several species recur as year-round residents in Narragansett Bay (P. pungens var. pungens, P. americana, P. multiseries, and P. calliantha). Various other species increased in frequency after 2015, and some appeared for the first time during the closure period. Notably, P. australis, a species prevalent in US West Coast HABs and known for high DA production, was not observed in Narragansett Bay until the 2017 closure but has been present in several years after the closures. Annual differences in Pseudo-nitzschia composition were correlated with physical and chemical conditions, predominantly water temperature. The long-term composition trends of Pseudo-nitzschia in Narragansett Bay serve as a baseline for identifying the introduction of new species, understanding shifting assemblages that contributed to the 2016-17 closures, and monitoring species that may be cause for future concern
Screencasting Information Literacy. Insights in pre-service teachers’ conception of online searching
Get PDFInformation Literacy (IL) has been named a key competence for the twenty-first century and is being progressively introduced in many compulsory school curricula. Nonetheless, the actual implementation of effective IL education cannot be carried out without the sound preparation of teachers. This study explores the naïve, pre-instruction conceptions of online information searching of pre-service pre-primary and primary teachers through the structured qualitative analysis of participant-produced screencasts. The results indicate that teachers have a mainly technical view of IL, leading them to focus on basic computer literacy skills (e.g., how to use a search engine) and to overlook mental processes (e.g., the definition of an information need or strategy). Implications for the development of pre-service teachers’ IL education are discussed
Clinical and epidemiological features in hospitalized young children with acute gastroenteritis in Taiwan: A multicentered surveillance through 2014–2017
No full textBackground/purpose: Acute gastroenteritis (AGE) remains a significant health issue in children. The worldwide evolution of pediatric AGE pathogens had been recorded since the introduction of rotavirus vaccine. Ten years after the rotavirus vaccine was introduced to the private sectors in Taiwan, a nationwide study was conducted to elucidate the epidemiological changes among major AGE pathogens. Methods: From January 2014 to December 2017, children younger than 5 years old, hospitalized with AGE at 10 hospitals across Taiwan were enrolled. Stool specimens were tested for Salmonella spp., Campylobacter spp., Clostridiodes difficile, norovirus, and rotavirus by polymerase chain reaction (PCR). The epidemiological and clinical information was collected. Results: Enteric pathogen were detected in 1983 (42.2%) of 4700 subjects, with Salmonella spp. (12.5%) being the leading cause of AGE, followed by norovirus (11.2%), rotavirus (8.7%), C. difficile (4.2%), Campylobacter spp. (1.0%), and a mixture of at least 2 of 5 above-mentioned pathogens (4.6%). The case distributions varied across different regions. In eastern Taiwan, rotavirus (21/131, 16.0%) remained the most common pathogen detected. The rotavirus vaccine uptake rate is significantly lower in patients with rotavirus AGE. Besides, rotavirus AGE frequently occurred in children with foreign parent(s), Taiwanese indigenous people, and those with the household monthly income \u3c NT$ 60,000. Conclusion: Salmonella spp. and norovirus were two major pathogens of pediatric AGE in Taiwan during 2014–17. Providing low-to middle-income households with free rotavirus vaccine nationwide and an industry-led act to reduce salmonellosis should be considered by the authorities
Investigating preservation of stable isotope ratios in subfossil deep-sea proteinaceous coral skeletons as paleo-recorders of biogeochemical information over multimillennial timescales
Get PDFPaleoproxy records in deep-sea proteinaceous coral skeletons can reconstruct past ocean conditions on centennial to millennial time scales. Commonly recovered subfossil specimens could potentially extend these archives through the Holocene. However, protein matrix stability and integrity of stable isotope proxies over multi-millennial timescales in such specimens have never been examined. Here we compare amino acid (AA) composition together with bulk and AA compound-specific carbon (δ13C) and nitrogen (δ15N) isotopes in live-collected and subfossil (∼9.6–11.6 kyrs BP) Kulamanamana haumeaae deep-sea coral specimens from the central Pacific to understand the effects of long-duration benthic oxic exposure on primary coral chemistry. We find large coupled shifts in bulk δ15N (∼7‰) and δ13C (∼2‰) in the outermost portion (0–10 mm) of the subfossil coral, coincident with extensive alteration of the protein matrix. Microstructural changes in skeletal texture coincide with higher C/N ratios (+0.8) and isotope-based amino acid degradation parameters (e.g. ΣV ≥ 3), indicating extensive degradation of seawater-exposed gorgonin. However, interior gorgonin (\u3e10 mm) retained amino acid molecular compositions (with exception of major Glycine loss) and bulk and amino acid-specific isotopic values that were similar to live-collected specimens. These results indicate that compound-specific isotope analysis of amino acids can reconstruct paleo-oceanographic biogeochemical and ecosystem information in subfossil corals beyond a clear diagenetic horizon, which is easily identifiable from an evaluation of C/N ratios together with the ΣV degradation proxy
The Aroma of Legitimacy in the Late Middle Ages
No full textGrowing from research undertaken for Rollo-Koster’s latest book, The Great Western Schism, 1378-1417: Performing Legitimacy, Performing Unity, this new article project emphasizes the sense of smell as a vehicle to inculcate political authority. Using several case studies delimited by “performances” of papacy, The Great Western Schism, 1378-1417: Performing Legitimacy, Performing Unity emphasizes the frequent recourse to the senses in the education and somewhat acculturation of audiences to political legitimacy and authority. But while seeing, hearing, tasting, and touching are overly emphasized by the historiography, smell (distinct from food and taste) has not been fully considered.
Using the example of the scented Golden Rose, a precious object that the pope offered to the most remarkable Christian of his time, Rollo-Koster discussed how the rose taught its audience (via its aroma) how to recognize legitimate authority, either sacred or profane. Since approximately the middle of the eleventh century the Golden rose was scented (it still is today). The ceremonial usually labeled Ordo Romanus XI (1140/1143) mentions the presence of musk in the rose during its benediction at the Roman Church of Santa Croce in Jerusalem on the last Sunday of Lent (in Laetere). Musk is the rarest and most prestigious of all perfumes. It is pungent and can be diluted hundreds of times without losing its fragrance. Cencius’ ceremonial, the Ordo Romanus XII (1192), adds that the Rose was perfumed with musk and balsam (rosam auream cum muschio et balsamo). Balsam, with incense, belongs to Christian liturgy. For example, both substances became mandatory in funerals’ liturgy. Still, and more importantly, mixed with olive oil balsam transformed into the holy chrism of consecration, and became the symbol of the Holy Ghost’s “presence.”
It can only be emphasized that the Rose and its musk were closely knit with the office of pope. Musk, and balsam helped define the institutional immaterial, office. But eventually the scented rose passed on to someone else, and with this passing the rose emphasized this time the legitimacy not of the donor but of the grantee