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In Pursuit of Ecosystem-Based Management for Narragansett Bay: An Overview of Previous Models and Roadmap for Future Research
No full textEcosystem models have emerged as vital tools for evaluating management strategies and are increasingly used by policymakers. We reviewed the history of modeling and identified research gaps based on policy needs for ecosystem-based management of Narragansett Bay (RI, USA)—a highly-impacted system with a history of research and monitoring dating back to the 1950s. There is a need to disentangle the impacts of nutrient reductions versus climate change on species interactions as well as understand the ecological and socio-economic tradeoffs of management actions. Within this context, we consider the following to be important for future research and creation of ecosystem models for Narragansett Bay: (i) account for multi-scale processes and patterns through two-way model coupling; (ii) incorporate human behavior as part of model predictions; and (iii) lessen the impact of model uncertainty by identifying robust management strategies that will sustain resources under a range of potential future scenarios. Ecosystem modeling that builds on prior models and is informed by knowledge gaps will be a powerful tool to operationalize ecosystem-based management in Narragansett Bay and globally, providing sustainable pathways for nature and people
Two canonically aerobic foraminifera express distinct peroxisomal and mitochondrial metabolisms
Get PDFCertain benthic foraminifera thrive in marine sediments with low or undetectable oxygen. Potential survival avenues used by these supposedly aerobic protists include fermentation and anaerobic respiration, although details on their adaptive mechanisms remain elusive. To better understand the metabolic versatility of foraminifera, we studied two benthic species that thrive in oxygen-depleted marine sediments. Here we detail, via transcriptomics and metatranscriptomics, differential gene expression of Nonionella stella and Bolivina argentea, collected from Santa Barbara Basin, California, USA, in response to varied oxygenation and chemical amendments. Organelle-specific metabolic reconstructions revealed these two species utilize adaptable mitochondrial and peroxisomal metabolism. N. stella, most abundant in anoxia and characterized by lack of food vacuoles and abundance of intracellular lipid droplets, was predicted to couple the putative peroxisomal beta-oxidation and glyoxylate cycle with a versatile electron transport system and a partial TCA cycle. In contrast, B. argentea, most abundant in hypoxia and contains food vacuoles, was predicted to utilize the putative peroxisomal gluconeogenesis and a full TCA cycle but lacks the expression of key beta-oxidation and glyoxylate cycle genes. These metabolic adaptations likely confer ecological success while encountering deoxygenation and expand our understanding of metabolic modifications and interactions between mitochondria and peroxisomes in protists
Biochemical and Regulatory Analyses of Xylanolytic Regulons in Caldicellulosiruptor bescii Reveal Genus-Wide Features of Hemicellulose Utilization
No full textCaldicellulosiruptor species scavenge carbohydrates from runoff containing plant biomass that enters hot springs and from grasses that grow in more moderate parts of thermal features. While only a few Caldicellulosiruptor species can degrade cellulose, all known species are hemicellulolytic. The most well-characterized species, Caldicellulosiruptor bescii, decentralizes its hemicellulase inventory across five different genomic loci and two isolated genes. Transcriptomic analyses, comparative genomics, and enzymatic characterization were utilized to assign functional roles and determine the relative importance of its six putative endoxylanases (five glycoside hydrolase family 10 [GH10] enzymes and one GH11 enzyme) and two putative exoxylanases (one GH39 and one GH3) in C. bescii. Two genus-wide conserved xylanases, C. bescii XynA (GH10) and C. bescii Xyl3A (GH3), had the highest levels of sugar release on oat spelt xylan, were in the top 10% of all genes transcribed by C. bescii, and were highly induced on xylan compared to cellulose. This indicates that a minimal set of enzymes are used to drive xylan degradation in the genus Caldicellulosiruptor, complemented by hemicellulolytic inventories that are tuned to specific forms of hemicellulose in available plant biomasses. To this point, synergism studies revealed that the pairing of specific GH family proteins (GH3, -11, and -39) with C. bescii GH10 proteins released more sugar in vitro than mixtures containing five different GH10 proteins. Overall, this work demonstrates the essential requirements for Caldicellulosiruptor to degrade various forms of xylan and the differences in species genomic inventories that are tuned for survival in unique biotopes with variable lignocellulosic substrates
The Effect of Rebate and Loan Incentives on Residential Heat Pump Adoption: Evidence from North Carolina
No full textElectrification can promote deep decarbonization to tackle climate change with a cleaner power grid. Electric heat pumps provide a feasible and energy-efficient way to replace fossil-fuel furnaces for space heating. Rebate and loan programs are the two most widely used incentives for residential heat pump installations in the U.S. This study compares the impacts of rebate and loan incentives on residential air-source heat pump adoption in North Carolina. First, our results show that the rebate program (450 per system) increases the adoption density by 13% in a year. Second, we find that the rebate program is more effective in promoting heat pump adoption for average consumers than two loan programs (annual loan interest rate: 9%, 3.9%). Third, we find the rebate program is less effective for low-income households than high-income households. Lastly, we compare the rebate with the loan programs in terms of cost-effectiveness and we find the rebate program is more cost-effective under certain circumstances
Optimal Shape Estimation and Methodologies for Towed Undersea Vehicles
Get PDFTeam 02 in part with Dr. Nassersharif, has been commissioned by the Naval Undersea Warfare Center to provide an optimal design and modeling for towed undersea vehicles. The proposed effort served to study, evaluate, and model the drag for the towing of cylindrical undersea vehicles. This project will model towing configurations for both single and multiple vehicle configurations. Recommendations were also made regarding the propulsion configuration of the leading vehicle. The proposed design solution aimed to achieve a drag coefficient of less than 0.3 to minimize the effect the towed vehicle may have on the range and endurance of its host. Range and endurance remain among the biggest factors that inhibit mission capability. For this reason, R.E.M.OR.A. was designed to induce well under a 500 Watt power loss from the drag of the vehicle(s). The effort included extensive initial research into methods that would aid in this study. Multiple C.F.D. simulations were run to obtain theoretical results for coefficients of drag on proposed shape estimations as well as the effects on varied surface roughness. As the Naval application has specified implications, one being undetected operation, measures were taken to minimize the acoustic power output of the proposed propulsion configurations. C.F.D.’s were also run on these configurations, that for a single screw propulsor and a 4 screw propulsor system. The efforts sought to reduce the noise output of the propulsion system to be less than 30 decibels. These targets were confirmed by in water testing of the proposed shape estimation where drag forces were obtained and respective coefficients calculated. From this testing quadratic models were created to predict power loss induced by full scaled model of the system. The proposed solution was found to have an almost negligible effect on full sized host vehicles, especially those that are nuclear powered. The loss of power for a single and dual vehicle both remained under 115 Watts after scaling test values obtained from in water testing. The experimental drag coefficients of these setups remained just under 0.3 with an average value of 0.286. These vehicles were optimized with a dynamic attachment point capable of varying the angle and point of attachment to the vehicle. This system allowed the operational target depth of 200-300ft
GermBurner: MechTech Company Limited
Get PDFTeam 13 was given a simple problem to solve: invent a design solution to a broad need for application. The purpose of this project as one of the invention teams was to design and produce an invention that has a large current day application and relativity. First was establishing the area of application that the group wanted to focus on. Collectively, a focus on portable sanitation was decided to be the route of most relevance and desire. With the ongoing COVID-19 pandemic, there has never been a more important time to keep yourself and the objects you frequently touch sanitary. To accomplish such a task, extensive research and development had to be conducted. After looking through literature, searching through patents, and deliberating as a group, a collective 120 concepts were generated and evaluated. They were evaluated using Pugh Analysis which eventually allowed for that 120 to be narrowed down to 3.
In order to then potentially separate an isolated winner, a Quality Function Development analysis was completed with the 3 final innovative ideas along with a few potential competitors. Ultimately, the winning invention was a phone case with integrated UV-C sanitation to conveniently clean a credit card of standard size. The design includes an internal power source that powers an arduino board and several UV-C LED lights. With a built-in rail system, the door to access the system, as well as the built-in tray that the card sits on, easily slides out for the desired card to be placed on. The case is a 2 piece ensemble, a polymer based, thin, inner shell and an PLA outer shell that contains the sanitation apparatus. This allows for the user to take the sanitation apparatus off if desired and still have a polymer case underneath for phone safety.
This full design was specked, drawn, generated 3 dimensionally, and finally prototyped. By generating 3-D renditions of the case, it was able to be printed and assembled in order to prove it physically met several design specifications the group had to meet. This ensured the case would not only be an effective form of sanitation for the desired need, but also maintained a desired aesthetic and size. Additional work was completed in the form of coding and electrical wiring. The UV-C LED chips were soldered to the PCB boards and successfully connected to the Arduino Nano which was properly coded to run the system for 60s. From there the 3 circuit boards were attached to the housing and connected to the power source, thus, the GermBurner was born
Robotics Process Automation
Get PDFMiniature Casting Corporation of Cranston, Rhode Island, proposed the robotics process automation project. Currently, secondary operations are performed by hand after the parts are cast on the factory floor. Workers must grab parts one by one and manually sand the tops and bottoms, and then promptly ream the inside tolerances using a drill bit. These workers can be utilized efficiently elsewhere in the factory if this process were to be automated. It is the wish of MiniCast to fully automate these tasks and involve a robotic arm in some way.
This is a project that primarily deals with process design, with the goal of successfully designing and implementing an automated system that meets the needs set by MiniCast. The process includes the execution of secondary operations on die-casted parts made of zinc. The parts that the project focuses on is a family of similarly shaped semi-truck key ignition housings, with the only difference between families being sizing. The secondary operations that must be automated include the sanding and reaming of any deformities that are a result of the casting process. In order to automate these tasks a series of processes had to be brainstormed, including the in-feed of the system, the automated sanding and reaming, as well as an exit process. The process of reaming is to be completed by a robotic arm with a reamer attachment. In total the team proposed 120 concepts for this project, however, through the process of elimination this was narrowed down to a more reasonable amount. Engineering analysis, as well as competitive analysis were performed in order to limit the amount of concepts the team had, the results of which are included later in this report.
During the design process the creation of a tray to hold parts during the secondary operations was created. This was the primary focus of the group, as everything else can be built around the tray design. Once the tray design was finalized the design of a conveyor system was also accomplished, as well as the recommendation of a robotic arm to MiniCast
Understanding the Public Perception of Available Scientific Resources in Coastal Southern Maine
Get PDFI have focused my education as an undergrad towards the effective communication of scientific fact to non-scientific groups. This area of study has recently been dubbed Science Communication and it encompasses the effective articulation, communication, and education of scientific topics to people who haven’t dedicated their lives to scientific study. A major component of effective Scientific Communication is understanding your audience and what kind of communication strategies are best for a chosen demographic.
I grew up in Ocean Park Maine, a small town on the coast of Southern Maine which drove my interest in Marine Science. With my experience in marine science and my focus on effective science communication, I knew I could build a project that would reflect my upbringing and my newly acquired experience.
I constructed a survey aimed at understanding the demographic I grew up in and how the scientific community, in particular their ability to communicate with non-scientific groups, is perceived. The survey was 10 questions long, approachable and non-intrusive, which made responding to it as appealing as I could make it. I published this survey in our community Facebook Group which gave back a great number of responses.
I proceeded to analyze the data and conduct statistical analysis on it to draw any significant conclusions. I then used the information I gained to construct an effective communication plan around the preferences and thoughts of our community. My hope is to take this kind of practice into my future with even more experience and expertise to construct community communication plans so that the scientists can more easily engage with the general public to share their incredible wealth of knowledge and experience with the world
