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An AIE organic zinc chloride complex scintillator, in which the metal halide serves as X-ray sensitizer for the organic component, is discovered to exhibit a light yield of 13 423 Photon per MeV and a radioluminescence decay lifetime of 5.24 ns.

 

Cell identification is an important yet difficult process in data analysis of biological images. Previously, we developed an automated cell identification method called CRF_ID and demonstrated its high performance in C. elegans whole-brain images (Chaudhary et al, 2021). However, because the method was optimized for whole-brain imaging, comparable performance could not be guaranteed for application in commonly used C. elegans multi-cell images that display a subpopulation of cells. Here, we present an advance CRF_ID 2.0 that expands the generalizability of the method to multi-cell imaging beyond whole-brain imaging. To illustrate the application of the advance, we show the characterization of CRF_ID 2.0 in multi-cell imaging and cell-specific gene expression analysis in C. elegans. This work demonstrates that high accuracy automated cell annotation in multi-cell imaging can expedite cell identification and reduce its subjectivity in C. elegans and potentially other biological images of various origins.

 

A rigorous methodology is developed for computing elastic fields generated by experimentally observed defect structures within grains in a polycrystal that has undergone tensile extension. An example application is made using a near-field high energy x-ray diffraction microscope measurement of a zirconium sample that underwent$13.6\mathrm{\%}$tensile extension from an initially well-annealed state. (Sub)grain boundary features are identified with apparent disclination line defects in them. The elastic fields of these features identified from the experiment are calculated.

 

Abstract We investigate the impacts of the neutrino cooling mechanism inside the neutron star (NS) core on the light curves of type I X-ray bursts and X-ray superbursts. From several observations of NS thermal evolution, physical processes of fast neutrino cooling, such as the direct Urca (DU) process, are indicated. They significantly decrease the surface temperature of NSs, though the cooling effect could be suppressed by nucleon superfluidity. In the present study, focusing on the DU process and nucleon superfluidity, we investigate the effects of NS cooling on the X-ray bursts using a general-relativistic stellar-evolution code. We find that the DU process leads to a longer recurrence time and higher peak luminosity, which could be obstructed by the neutrons’ superfluidity. We also apply our burst models to the comparison with Clocked burster GS 1826−24, and to the recurrence time of a superburst triggered by carbon ignition. These effects are significant within a certain range of binary parameters and the uncertainty of the NS equation of state. 

This paper presents an innovative approach to improve engineering students’ problem-solving skills by implementing think-aloud exercises. Sometimes engineering students claim they do not know where to start with the problem-solving process, or they are not sure how to proceed to the next steps when they get stuck. A systematic training that focuses on the problem-solving process and the justification of each step could help. Think-aloud techniques help make the invisible mental processes visible to learners. Engineering think-aloud technique engages students and helps them make their way through a solving process step-by-step, reasoning along with them. In this study, a multiple faceted systematic approach that integrates think-aloud exercises through video assignments and oral exams were developed and implemented in two pilot engineering classes. We present our think-aloud exercises and oral exams structures in each of the courses and their impacts on students' learning outcomes, and students’ perceptions towards the pedagogical approach. Both quantitative and qualitative results show that the think-aloud exercise assignments and oral exams enhance students’ problem-solving skills and promote learning.