2,707 research outputs found

    Production of methyl ethyl ketone from biomass using a hybrid biochemical/catalytic approach

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    The recent demand for sustainable routes to fuels and chemicals has led to an increased amount of research in conversion of natural resources. A potential approach for conversion of biomass to fuels and chemicals is to combine biochemical and chemical processes. This research used microbial fermentation to produce 2,3-butanediol, which was then converted to methyl ethyl ketone by dehydration over a solid acid catalyst. The fermentation process was performed using the bacteria Klebsiella oxytoca (K.O). 2,3-butanediol then dehydrated to form methyl ethyl ketone on a solid acid catalyst, the proton form of ZSM-5, and heat. The goal was to determine the reaction kinetics of 2,3-butanediol dehydration over ZSM-5, and to demonstrate the hybrid biochemical/thermochemical approach for synthesizing chemicals from biomass. It was found that ZSM-5 produced methyl ethyl ketone with high selectivity (greater than 90%), and could convert fermentative 2,3-butanediol to methyl ethyl ketone. The reaction order of 2,3-butanediol dehydration was found to be slightly large than one, and an activation energy of 32.3 kJ/mol was measured

    Naked teaching: uncovering selves in the reflexive classroom

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    AbstractThis autoethnography explores our experiences teaching an undergraduate autoethnographycourse entitled, ‘Writing Lives’. We, Keith and Nathan, Professor and Doctoral candidate,convey narrative scenes and reflections of sharing and analysing our published stories withstudents, working with students through the process of writing their personal stories, andtransformative moments during the course. We emphasise a vulnerable, reflexive, andempathetic approach to teaching and learning that allows students and teachers to uncoveraspects of who they are and hope to be in the classroom. This work advocates a number ofunique benefits to autoethnographic practices that foster open and intimate bond

    Community Transportation Academy: Course Curriculum and Implementation Handbook

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    A Community Transportation Academy (CTA) is a course that harnesses the knowledge, technical expertise and passions of practicing transportation professionals in a city to immerse a cohort of interested and dedicated community members in transportation issues over a two to three month curriculum. The CTA curriculum was developed by drawing from the Portland Traffic and Transportation (PTT or Portland CTA) course, along with the Wasatch Transportation Academy (WTA or Wasatch CTA, which was inspired by the Portland course). Planning academy courses in cities around the country are also good models to look to for how to structure and operate such a course. However, the nature of the transportation course is that it goes into much greater depth on a specific topic, allowing the participant to go deeper into transportation history and technical discussions and develop a greater understanding of the agencies and policies involved

    Dynamics of mercury in eared grebes on Great Salt Lake

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    Launching the Wasatch Transportation Academy

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    The “Community Transportation Academy” model seeks to break down the barriers for community members to participate in transportation decision-making processes. Since 1991, the Portland Traffic and Transportation Course has held at least one course each year, connecting Portland residents with top planners, engineers, and decision-makers from agencies working on transportation in the region, with the goal of conveying the factors professionals consider, ranging from technical considerations, legal and policy mandates, other tradeoffs, and how the community can engage with and influence decisions. This project sought to implement a transportation academy in the Salt Lake City region inspired by the Portland course, using a handbook and report developed as part of a prior NITC-funded study. This report details the implementation of the Wasatch Transportation Academy. Using a curriculum handbook developed in 2015 based on the Portland course, this project sought to adapt the curriculum for the Salt Lake City region. The project brought in partners from the region’s municipalities and regional and state transportation agencies to create the first of what is hoped to be a continuing community-based course in transportation planning and decision-making. The course ran for eight weeks during January-March 2022, reaching a total of 49 students and concluding with a suite of 18 student-led project presentations and a field trip of a local transportation project in the process of being implemented. Student feedback from a post-course survey showed a high degree of satisfaction across a number of pedagogic factors, with a strongly positive net promoter score, indicating a likelihood of continued success for the course in future years. Experiences from the first run of the course suggest improvements to course structure and curriculum that would extend the course to a 10-week format (like Portland’s), and a shifting geographic focus to capture differing substantive foci and engage a broader set of students and stakeholders

    Calculating expected DNA remnants from ancient founding events in human population genetics

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    <p>Abstract</p> <p>Background</p> <p>Recent advancements in sequencing and computational technologies have led to rapid generation and analysis of high quality genetic data. Such genetic data have achieved wide acceptance in studies of historic human population origins and admixture. However, in studies relating to small, recent admixture events, genetic factors such as historic population sizes, genetic drift, and mutation can have pronounced effects on data reliability and utility. To address these issues we conducted genetic simulations targeting influential genetic parameters in admixed populations.</p> <p>Results</p> <p>We performed a series of simulations, adjusting variable values to assess the affect of these genetic parameters on current human population studies and what these studies infer about past population structure. Final mean allele frequencies varied from 0.0005 to over 0.50, depending on the parameters.</p> <p>Conclusion</p> <p>The results of the simulations illustrate that, while genetic data may be sensitive and powerful in large genetic studies, caution must be used when applying genetic information to small, recent admixture events. For some parameter sets, genetic data will not be adequate to detect historic admixture. In such cases, studies should consider anthropologic, archeological, and linguistic data where possible.</p

    A Method to Estimate Climate-Critical Construction Materials Applied to Seaport Protection

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    Climate adaptation for coastal infrastructure projects raises unique challenges because global-scale environmental changes may require similar projects to be completed in many locations over the same time frame. Existing methods to forecast resource demand and capacity do not consider this phenomenon of a global change affecting many localities and the resulting increased demand for resources. Current methods do not relate to the most up-to-date climate science information, and they are too costly or too imprecise to generate global, regional, and local forecasts of “climate-critical resources” that will be required for infrastructure protection. They either require too much effort to create the many localized designs or are too coarse to consider information sources about local conditions and structure-specific engineering knowledge. We formalized the concept of a “minimum assumption credible design” (MACD) to leverage available local information (topography/bathymetry and existing infrastructure) and the essential engineering knowledge and required construction materials (i.e., a design cross-section template). The aggregation of the resources required for individual local structures then forecasts the resource demand for global adaptation projects. We illustrate the application of the MACD method to estimate the demand for construction materials critical to protect seaports from sea-level-rise-enhanced storm surges. We examined 221 of the world’s 3,300+ seaports to calculate the resource requirements for a coastal storm surge protection structure suited to current upper-bound projections of two meters of sea level rise by 2100. We found that a project of this scale would require approximately 436 million cubic meters of construction materials, including cement, sand, aggregate, steel rebar, and riprap. For cement alone, ∌49 million metric tons would be required. The deployment of the MACD method would make resource forecasts for adaptation projects more transparent and widely accessible and would highlight areas where current engineering knowledge or material, engineering workforce, and equipment capacity fall short of meeting the demands of adaptation projects

    Nontargeted biomonitoring of halogenated organic compounds in two ecotypes of bottlenose dolphins (Tursiops truncatus) from the Southern California Bight.

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    Targeted environmental monitoring reveals contamination by known chemicals, but may exclude potentially pervasive but unknown compounds. Marine mammals are sentinels of persistent and bioaccumulative contaminants due to their longevity and high trophic position. Using nontargeted analysis, we constructed a mass spectral library of 327 persistent and bioaccumulative compounds identified in blubber from two ecotypes of common bottlenose dolphins (Tursiops truncatus) sampled in the Southern California Bight. This library of halogenated organic compounds (HOCs) consisted of 180 anthropogenic contaminants, 41 natural products, 4 with mixed sources, 8 with unknown sources, and 94 with partial structural characterization and unknown sources. The abundance of compounds whose structures could not be fully elucidated highlights the prevalence of undiscovered HOCs accumulating in marine food webs. Eighty-six percent of the identified compounds are not currently monitored, including 133 known anthropogenic chemicals. Compounds related to dichlorodiphenyltrichloroethane (DDT) were the most abundant. Natural products were, in some cases, detected at abundances similar to anthropogenic compounds. The profile of naturally occurring HOCs differed between ecotypes, suggesting more abundant offshore sources of these compounds. This nontargeted analytical framework provided a comprehensive list of HOCs that may be characteristic of the region, and its application within monitoring surveys may suggest new chemicals for evaluation
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