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  1. We present a study that examines the effects of guidance on learning about addressing ill-defined problems in undergraduate bi- ology education. Two groups of college students used an online labo- ratory named VERA to learn about ill-defined ecological phenomena. While one group received guidance, such as giving the learners a specific problem and instruction on problem-solving methods, the other group re- ceived minimal guidance. The results indicate that, while performance in a problem-solving task was not different between groups receiving more vs. minimal guidance, the group that received minimal guidance adopted a more exploratory strategy and generated more interesting modelsmore »of the given phenomena in a problem-solving task.« less
    Free, publicly-accessible full text available June 1, 2023
  2. Free, publicly-accessible full text available January 15, 2023
  3. Virtual laboratories that enable novice scientists to construct, evaluate and revise models of complex systems heavily involve parameter estimation tasks. We seek to understand novice strategies for parameter estimation in model exploration to design better cognitive supports for them. We conducted a study of 50 college students for a parameter estimation task in exploring an ecological model. We identified three types of behavioral patterns and their underlying cognitive strategies. Specifically, the students used systematic search, problem decomposition and reduction, and global search followed by local search as their cognitive strategies
  4. Modeling is an important aspect of scientific problem-solving. How- ever, modeling is a difficult cognitive process for novice learners in part due to the high dimensionality of the parameter search space. This work investigates 50 college students’ parameter search behaviors in the context of ecological modeling. The study revealed important differences in behaviors of successful and unsuccessful students in navigating the parameter space. These differences suggest opportunities for future development of adaptive cognitive scaffolds to support different classes of learners
  5. Citizen scientists have the potential to expand scientific research. The virtual research assistant called VERA empowers citizen scientists to engage in environmental science in two ways. First, it automatically generates simulations based on the conceptual models of ecological phenomena for repeated testing and feedback. Second, it leverages the Encyclopedia of Life biodiversity knowledgebase to support the process of model construction and revision.
  6. A bstract A search is presented for a heavy W′ boson resonance decaying to a B or T vector-like quark and a t or a b quark, respectively. The analysis is performed using proton-proton collisions collected with the CMS detector at the LHC. The data correspond to an integrated luminosity of 138 fb − 1 at a center-of-mass energy of 13 TeV. Both decay channels result in a signature with a t quark, a Higgs or Z boson, and a b quark, each produced with a significant Lorentz boost. The all-hadronic decays of the Higgs or Z boson and ofmore »the t quark are selected using jet substructure techniques to reduce standard model backgrounds, resulting in a distinct three-jet W′ boson decay signature. No significant deviation in data with respect to the standard model background prediction is observed. Upper limits are set at 95% confidence level on the product of the W′ boson cross section and the final state branching fraction. A W′ boson with a mass below 3.1 TeV is excluded, given the benchmark model assumption of democratic branching fractions. In addition, limits are set based on generalizations of these assumptions. These are the most sensitive limits to date for this final state.« less
    Free, publicly-accessible full text available September 1, 2023
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  10. A bstract Results are presented from a search for charged-lepton flavor violating (CLFV) interactions in top quark production and decay in pp collisions at a center-of-mass energy of 13 TeV. The events are required to contain one oppositely charged electron-muon pair in the final state, along with at least one jet identified as originating from a bottom quark. The data correspond to an integrated luminosity of 138 fb − 1 , collected by the CMS experiment at the LHC. This analysis includes both the production (q → e μ t) and decay (t → e μ q) modes of themore »top quark through CLFV interactions, with q referring to a u or c quark. These interactions are parametrized using an effective field theory approach. With no significant excess over the standard model expectation, the results are interpreted in terms of vector-, scalar-, and tensor-like CLFV four-fermion effective interactions. Finally, observed exclusion limits are set at 95% confidence levels on the respective branching fractions of a top quark to an e μ pair and an up (charm) quark of 0 . 13 × 10 − 6 (1 . 31 × 10 − 6 ), 0 . 07 × 10 − 6 (0 . 89 × 10 − 6 ), and 0 . 25 × 10 − 6 (2 . 59 × 10 − 6 ) for vector, scalar, and tensor CLFV interactions, respectively.« less
    Free, publicly-accessible full text available June 1, 2023