skip to main content


Title: Ultrashort􀀁Pulse-beam Characterization Using Femtosecond Interferometric􀀁Shack-Hartmann Frequency Resolved Optical Gating
We introduce a self-referenced system that retrieves the full spatio-temporal profile of an ultrashort pulse using a Shack-Hartmann and second harmonic generation FROG. The key feature is the precise co-location of a spectral phase measurement at one spatial position with the spectrally resolved spatial measurements.  more » « less
Award ID(s):
1903709
PAR ID:
10416591
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Quantum Electronics and Laser Science
ISSN:
2160-8989
Page Range / eLocation ID:
1-2
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Abstract

    Spatial proteomics can visualize and quantify protein expression profiles within tissues at single-cell resolution. Although spatial proteomics can only detect a limited number of proteins compared to spatial transcriptomics, it provides comprehensive spatial information with single-cell resolution. By studying the spatial distribution of cells, we can clearly obtain the spatial context within tissues at multiple scales. Spatial context includes the spatial composition of cell types, the distribution of functional structures, and the spatial communication between functional regions, all of which are crucial for the patterns of cellular distribution. Here, we constructed a comprehensive spatial proteomics functional annotation knowledgebase, scProAtlas (https://relab.xidian.edu.cn/scProAtlas/#/), which is designed to help users comprehensively understand the spatial context within different tissue types at single-cell resolution and across multiple scales. scProAtlas contains multiple modules, including neighborhood analysis, proximity analysis and neighborhood network, to comprehensively construct spatial cell maps of tissues and multi-modal integration, spatial gene identification, cell-cell interaction and spatial pathway analysis to display spatial variable genes. scProAtlas includes data from eight spatial protein imaging techniques across 15 tissues and provides detailed functional annotation information for 17 468 394 cells from 945 region of interests. The aim of scProAtlas is to offer a new insight into the spatial structure of various tissues and provides detailed spatial functional annotation.

     
    more » « less
  2. Women reliably perform worse than men on measures of spatial ability, particularly those involving mental rotation. At the same time, females also report higher levels of spatial anxiety than males. What remains unclear, however, is whether and in what ways gender differences in these cognitive and affective aspects of spatial processing may be interrelated. Here, we tested for robust gender differences across six different datasets in spatial ability and spatial anxiety (N = 1257, 830 females). Further, we tested for bidirectional mediation effects. We identified indirect relations between gender and spatial skills through spatial anxiety, as well as between gender and spatial anxiety through spatial skills. In the gender → spatial anxiety → spatial ability direction, spatial anxiety explained an average of 22.4% of gender differences in spatial ability. In the gender → spatial ability → spatial anxiety direction, spatial ability explained an average of 25.9% of gender differences in spatial anxiety. Broadly, these results support a strong relation between cognitive and affective factors when explaining gender differences in the spatial domain. However, the nature of this relation may be more complex than has been assumed in previous literature. On a practical level, the results of this study caution the development of interventions to address gender differences in spatial processing which focus primarily on either spatial anxiety or spatial ability until such further research can be conducted. Our results also speak to the need for future longitudinal work to determine the precise mechanisms linking cognitive and affective factors in spatial processing.

     
    more » « less
  3. A natural language interface (NLI) to databases is an interface that translates a natural language question to a structured query that is executable by database management systems (DBMS). However, an NLI that is trained in the general domain is hard to apply in the spatial domain due to the idiosyncrasy and expressiveness of the spatial questions. Inspired by the machine comprehension model, we propose a spatial comprehension model that is able to recognize the meaning of spatial entities based on the semantics of the context. The spatial semantics learned from the spatial comprehension model is then injected to the natural language question to ease the burden of capturing the spatial-specific semantics. With our spatial comprehension model and information injection, our NLI for the spatial domain, named SpatialNLI, is able to capture the semantic structure of the question and translate it to the corresponding syntax of an executable query accurately. We also experimentally ascertain that SpatialNLI outperforms state-of-the-art methods. 
    more » « less
  4. There is significant work indicating that spatial ability has correlations to student success in STEM programs. Work also shows that spatial ability correlates to professional success in respective STEM fields. Spatial ability has thus been a focus of research in engineering education for some time. Spatial interventions have been developed to improve student’s spatial ability that range from physical manipulatives to the implementation of entire courses. These interventions have had positive impact upon student success and retention. Currently, researchers rely on a variety of different spatial ability instruments to quantify participants spatial ability. Researchers classify an individual’s spatial ability as the performance indicated by their results on such an instrument. It is recognized that this measured performance is constrained by the spatial construct targeted with that spatial instrument. As such, many instruments are available for the researchers use to assess the variety of constructs of spatial ability. Examples include the Purdue Spatial Visualization Test of Rotations (PSVTR), the Mental Cutting Test (MCT), and the Minnesota Paper Foam Board Test. However, at this time, there are no readily accessible spatial ability instruments that can be used to assess spatial ability in a blind or low vision population (BLV). Such an instrument would not only create an instrument capable of quantifying the impacts of spatially focused interventions upon BLV populations but also gives us a quantitative method to assess the effectiveness of spatial curriculum for BLV students. Additionally, it provides a method of assessing spatial ability development from tactile perspective, a new avenue for lines of research that expand beyond the visual methods typically used. This paper discusses the development of the Tactile Mental Cutting Test (TMCT), a non-visually accessible spatial ability instrument, developed and used with a BLV population. Data was acquired from individuals participating in National Federation of the Blind (NFB) Conventions across the United States as well as NFB sponsored summer engineering programs. The paper reports on a National Science Foundation funded effort to garner initial research findings on the application of the TMCT. It reports on initial findings of the instrument’s validity and reliability, as well as the development of the instrument over the first three years of this project. 
    more » « less
  5. null (Ed.)
    Abstract Background Prior research has revealed positive effects of spatial activity participation (e.g., playing with blocks, sports) on current and future spatial skills. However, research has not examined the degree to which spatial activity participation remains stable over time, and little is known about how participating in spatial activities at multiple points in development impacts spatial thinking. In this study, adolescents completed measures of spatial thinking and questionnaires assessing their current and previous participation in spatial activities. Results Participation in childhood spatial activities predicted adolescent spatial activity participation, and the relation was stronger for females than for males. Adolescents’ current participation in spatial activities predicted spatial thinking skills, whereas participation in childhood spatial activities predicted adolescents’ spatial habits of mind, even when accounting for factors such as gender and academic performance. No cumulative benefit was incurred due to participating in spatial activities in both childhood and adolescence, and a lack of spatial activities in childhood was not made up for by later spatial activity participation. Conclusions These findings reveal a consistently positive relationship in spatial activity participation between childhood and adolescence. Results highlight the importance of participating in spatial activities during childhood, and underscore the differential impact that participation in spatial activities during childhood versus adolescence has on different facets of adolescents’ spatial thinking. Implications for the timing of interventions is discussed. 
    more » « less