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1. Multi-label activity recognition using activity-specific features and activity correlations

   https://doi.org/10.1109/CVPR46437.2021.01439  

   Zhang Y, Li X ( June 2021 , 2021 IEEE/CVF Conference on Computer Vision and Pattern Recognition)
2. Protecting activity of desiccated enzymes

   https://doi.org/10.1002/pro.3604  

   Piszkiewicz, Samantha ; Gunn, Kathryn H. ; Warmuth, Owen ; Propst, Ashlee ; Mehta, Aakash ; Nguyen, Kenny H. ; Kuhlman, Elizabeth ; Guseman, Alex J. ; Stadmiller, Samantha S. ; Boothby, Thomas C. ; et al ( March 2019 , Protein Science)

   Protein‐based biological drugs and many industrial enzymes are unstable, making them prohibitively expensive. Some can be stabilized by formulation with excipients, but most still require low temperature storage. In search of new, more robust excipients, we turned to the tardigrade, a microscopic animal that synthesizes cytosolic abundant heat soluble (CAHS) proteins to protect its cellular components during desiccation. We find that CAHS proteins protect the test enzymes lactate dehydrogenase and lipoprotein lipase against desiccation‐, freezing‐, and lyophilization‐induced deactivation. Our data also show that a variety of globular and disordered protein controls, with no known link to desiccation tolerance, protect our test enzymes. Protection of lactate dehydrogenase correlates, albeit imperfectly, with the charge density of the protein additive, suggesting an approach to tune protection by modifying charge. Our results support the potential use of CAHS proteins as stabilizing excipients in formulations and suggest that other proteins may have similar potential.

    

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3. Spatial representability of neuronal activity

   https://doi.org/10.1038/s41598-021-00281-y  

   Akhtiamov, D. ; Cohn, A. G. ; Dabaghian, Y. ( October 2021 , Scientific Reports)

   A common approach to interpreting spiking activity is based on identifying the firing fields—regions in physical or configuration spaces that elicit responses of neurons. Common examples include hippocampal place cells that fire at preferred locations in the navigated environment, head direction cells that fire at preferred orientations of the animal’s head, view cells that respond to preferred spots in the visual field, etc. In all these cases, firing fields were discovered empirically, by trial and error. We argue that the existence and a number of properties of the firing fields can be established theoretically, through topological analyses of the neuronal spiking activity. In particular, we use Leray criterion powered by persistent homology theory, Eckhoff conditions and Region Connection Calculus to verify consistency of neuronal responses with a single coherent representation of space.

    

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4. Synchronization of world economic activity

   https://doi.org/10.1063/1.5001820  

   Groth, Andreas ; Ghil, Michael ( December 2017 , Chaos: An Interdisciplinary Journal of Nonlinear Science)
5. Activity triangles: a new approach to measure activity spaces

   https://doi.org/10.1007/s10109-023-00414-z  

   Sila-Nowicka, Katarzyna ; Fotheringham, A Stewart ; Demšar, Urška ( October 2023 , Journal of Geographical Systems)

   There is an on-going challenge to describe, analyse and visualise the actual and potential extent of human spatial behaviour. The concept of an activity space has been used to examine how people interact with their environment and how the actual or potential spatial extent of individual spatial behaviour can be defined. In this paper, we introduce a new method for measuring activity spaces. We first focus on the definitions and the applications of activity space measures, identifying their respective limitations. We then present our new method, which is based on the theoretical concept of significant locations, that is, places where people spent most of their time. We identify locations of significant places from GPS trajectories and define the activity space of an individual as a set of the first three significant places forming a so-called “activity triangle”. Our new method links the distances travelled for different activities to whether or not people group their activities, which is not possible using existing methods of measuring activity spaces. We test our method on data from a GPS-based travel survey across three towns is Scotland and look at the variations in size and shape of the designed activity triangle among people of different age and gender. We also compare our activity triangle with five other activity spaces and conclude by providing possible routes for improvement of activity space measures when using real human movement data (GPS data).

    

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