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  1. ; ; ; ; ; ; ( , LAK 2024 (accepted))
    This exploratory study delves into the complex challenge of analyzing and interpreting student responses to mathematical problems, typically conveyed through image formats within online learning platforms. The main goal of this research is to identify and differentiate various student strategies within a dataset comprising image-based mathematical work. A comprehensive approach is implemented, including various image representation, preprocessing, and clustering techniques, each evaluated to fulfill the study’s objectives. The exploration spans several methods for enhanced image representation, extending from conventional pixel-based approaches to the innovative deployment of CLIP embeddings. Given the prevalent noise and variability in our dataset, an ablation study is conducted to meticulously evaluate the impact of various preprocessing steps, assessing their potency in eradicating extraneous backgrounds and noise to more precisely isolate relevant mathematical content. Two clustering approaches—k-means and hierarchical clustering—are employed to categorize images based on student strategies that underlies their responses. Preliminary results underscore the hierarchical clustering method could distinguish between student strategies effectively. Our study lays down a robust framework for characterizing and understanding student strategies in online mathematics problem-solving, paving the way for future research into scalable and precise analytical methodologies while introducing a novel open-source image dataset for the learning analytics research community. 
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    Free, publicly-accessible full text available January 1, 2025
  2. ; ; ; ; ( , Applied sciences)
    Full Text Available 
  3. ; ; ; ; ; ( , Science advances)
    Ultra-miniaturized microendoscopes are vital for numerous biomedical applications. Such minimally invasive imagers allow for navigation into hard-to-reach regions and observation of deep brain activity in freely moving animals. Conventional solutions use distal microlenses. However, as lenses become smaller and less invasive, they develop greater aberrations and restricted fields of view. In addition, most of the imagers capable of variable focusing require mechanical actuation of the lens, increasing the distal complexity and weight. Here, we demonstrate a distal lens-free approach to microendoscopy enabled by computational image recovery. Our approach is entirely actuation free and uses a single pseudorandom spatial mask at the distal end of a multicore fiber. Experimentally, this lensless approach increases the space-bandwidth product, i.e., field of view divided by resolution, by threefold over a best-case lens- based system. In addition, the microendoscope demonstrates color resolved imaging and refocusing to 11 distinct depth planes from a single camera frame without any actuated parts. 
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    Full Text Available 
  4. ; ; ; ( , Future generation computer systems)
    Accepted Manuscript Full Text Available
  5. ; ; ; ; ; ; ; ; ( , Experimental Physiology)
    New Findings

    What is the central question of this study?

    What is the impact of airway cholinergic history on the properties of airway mucus secretion in a cystic fibrosis‐like environment?

    What is the main finding and its importance?

    Prior cholinergic challenge slightly modifies the characteristics of mucus secretion in response to a second cholinergic challenge in a diminished bicarbonate and chloride transport environment. Such modifications might lead to retention of mucus on the airway surface, thereby potentiating exacerbations of airway disease.

     Abstract

    Viral infections precipitate exacerbations in many airway diseases, including asthma and cystic fibrosis. Although viral infections increase cholinergic transmission, few studies have examined how cholinergic history modifies subsequent cholinergic responses in the airway. In our previous work, we found that airway resistance in response to a second cholinergic challenge was increased in young pigs with a history of airway cholinergic stimulation. Given that mucus secretion is regulated by the cholinergic nervous system and that abnormal airway mucus contributes to exacerbations of airway disease, we hypothesized that prior cholinergic challenge would also modify subsequent mucus responses to a secondary cholinergic challenge. Using our established cholinergic challenge–rechallenge model in pigs, we atomized the cholinergic agonist bethanechol or saline control to pig airways. Forty‐eight hours later, we removed tracheas and measured mucus secretion properties in response to a second cholinergic stimulation. The second cholinergic stimulation was conducted in conditions of diminished chloride and bicarbonate transport to mimic a cystic fibrosis‐like environment. In pigs previously challenged with bethanechol, a second cholinergic stimulation produced a mild increase in sheet‐like mucus films; these films were scarcely observed in animals originally challenged with saline control. The subtle increase in mucus films was not associated with changes in mucociliary transport. These data suggest that prior cholinergic history might modify mucus secretion characteristics with subsequent stimulation in certain environmental conditions or disease states. Such modifications and/or more repetitive stimulation might lead to retention of mucus on the airway surface, thereby potentiating exacerbations of airway disease.

     
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  6. ; ; ; ; ; ; ; ; ; ; et al ( , Physics Letters B)
    Free, publicly-accessible full text available November 1, 2024
  7. ; ; ; ; ; ; ; ; ; ; et al ( , Physics Letters B)
    Free, publicly-accessible full text available October 1, 2024
  8. ; ; ; ; ; ; ; ; ; ; et al ( , Physical Review C)
    Free, publicly-accessible full text available September 1, 2024
  9. ; ; ; ; ; ; ; ; ; ; et al ( , Journal of High Energy Physics)
    A<sc>bstract</sc>

    Measurements of the production of electrons from heavy-flavour hadron decays in pp collisions at$$ \sqrt{s} $$s= 13 TeV at midrapidity with the ALICE detector are presented down to a transverse momentum (pT) of 0.2 GeV/cand up topT= 35 GeV/c, which is the largest momentum range probed for inclusive electron measurements in ALICE. In p-Pb collisions, the production cross section and the nuclear modification factor of electrons from heavy-flavour hadron decays are measured in thepTrange 0.5< pT<26 GeV/cat$$ \sqrt{s_{\textrm{NN}}} $$sNN= 8.16 TeV. The nuclear modification factor is found to be consistent with unity within the statistical and systematic uncertainties. In both collision systems, first measurements of the yields of electrons from heavy-flavour hadron decays in different multiplicity intervals normalised to the multiplicity-integrated yield (self-normalised yield) at midrapidity are reported as a function of the self-normalised charged-particle multiplicity estimated at midrapidity. The self-normalised yields in pp and p-Pb collisions grow faster than linear with the self-normalised multiplicity. A strongpTdependence is observed in pp collisions, where the yield of high-pTelectrons increases faster as a function of multiplicity than the one of low-pTelectrons. The measurement in p-Pb collisions shows nopTdependence within uncertainties. The self-normalised yields in pp and p-Pb collisions are compared with measurements of other heavy-flavour, light-flavour, and strange particles, and with Monte Carlo simulations.

     
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    Free, publicly-accessible full text available August 1, 2024
  10. ; ; ; ; ; ; ; ; ; ; et al ( , Physical Review D)
    Free, publicly-accessible full text available August 1, 2024