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Defect patterns on the curved surface of fish retinae suggest a mechanism of cone mosaic formation
User Collection
- Creator:
- Nunley, Hayden, Nagashima, Mikiko, Martin, Kamirah, Lorenzo Gonzalez, Alcides, Suzuki, Sachihiro C., Norton, Declan A., Wong, Rachel O. L., Raymond, Pamela A., and Lubensky, David K.
- Description:
- The outer epithelial layer of zebrafish retinae contains a crystalline array of cone photoreceptors, called the cone mosaic. As this mosaic grows by mitotic addition of new photoreceptors at the rim of the hemispheric retina, topological defects, called “Y-Junctions”, form to maintain approximately constant cell spacing. The generation of topological defects due to growth on a curved surface is a distinct feature of the cone mosaic not seen in other well-studied biological patterns like the R8 photoreceptor array in the _ Drosophila compound eye. Since defects can provide insight into cell-cell interactions responsible for pattern formation, here we characterize the arrangement of cones in individual Y-Junction cores (see Set of images for Figures 1 and 2 and 6 and Supplementary Figure 7) as well as the spatial distribution of Y-junctions across entire retinae (see Dataset for analyzing spatial distribution of Y-junctions in flat-mounted retinae). We find that for individual Y-junctions, the distribution of cones near the core corresponds closely to structures observed in physical crystals (see Set of images for Figures 1 and 2 and 6 and Supplementary Figure 7). In addition, Y-Junctions are organized into lines, called grain boundaries, from the retinal center to the periphery (see Dataset for analyzing spatial distribution of Y-junctions in flat-mounted retinae and Dataset for measuring tendency of Y-junctions to line up into grain boundaries during incorporation into retinae). In physical crystals, regardless of the initial distribution of defects, defects can coalesce into grain boundaries via the mobility of individual particles. By imaging in live fish, we demonstrate that grain boundaries in the cone mosaic instead appear during initial mosaic formation, without requiring defect motion (see Dataset for measuring tendency of Y-junctions to line up into grain boundaries during incorporation into retinae and Dataset for analyzing Y-junction motion in live fish retinae). Motivated by this observation, we show that a computational model of repulsive cell-cell interactions generates a mosaic with grain boundaries (see Code and example simulations of phase-field crystal model (for cone mosaic formation)). In contrast to paradigmatic models of fate specification in mostly motionless cell packings (see Code and accompanying input data for simulating lateral inhibition on motionless cell packing), this finding emphasizes the role of cell motion, guided by cell-cell interactions during differentiation, in forming biological crystals. Such a route to the formation of regular patterns may be especially valuable in situations, like growth on a curved surface, where the resulting long-ranged, elastic, effective interactions between defects can help to group them into grain boundaries.
- Keyword:
- zebrafish cone mosaic, lattice vectors, topological defects, tissue patterning, grain boundaries, lateral inhibition, photoconversion, phase-field crystal model, and defect motion
- Discipline:
- Science
7Works -
- Creator:
- Moniri, Saman and Shahani, Ashwin J.
- Description:
- The data is comprised of 20 .hdf files of the X-ray projections recorded during isothermal annealing of Zn-Mg samples, at discrete time-steps shown below for files names ending in ‘...30141’ to ‘…30161’: 30141: prior to annealing; 30142: 1 min annealing; 30143: 3 min; 30144: 5 min; 30145: 7 min; 30146: 10 min; 30147: 15 min; 30148: 20 min; 30150: 31 min; 30151: 1 hr; 30152: 2 hr; 30153: 3 hr; 30154: 4 hr; 30155: 5 hr; 30156: 6 hr; 30157:7 hr; 30158: 8 hr; 30159:9 hr; 30160: 9 hr, 10 min; 30161: 10 hr The raw data file is in .hdf format and can be reconstructed into .tiff, e.g., by using the TomoPy toolbox in Python.
- Keyword:
- Spiral eutectics
- Discipline:
- Engineering
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- Creator:
- Abid, Chaima, Kessentini, Marouane, Alizadeh, Vahid, Dhaouadi, Mouna, and Kazman, Rick
- Description:
- Data about the evaluation of the refactorings impact on security.
- Discipline:
- Science
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- Creator:
- Moniri, Saman, Bale, Hrishikesh , Volkenandt, Tobias, Wang, Yeqing, Gao, Jianrong, Lu, Tianxian, Sun, Kai, and Shahani, Ashwin J.
- Description:
- The data file contains (1) the grayscale images of the nano-tomography experiments that can be segmented into binary images and visualized to show the 3D morphology of spiral eutectics; and (2) crystallographic orientation maps of serial-sectioned sample, which can be processed in a variety of EBSD software packages.
- Keyword:
- crystallization, chirality, self-organization, and spiral eutectics
- Citation to related publication:
- Moniri, S., Bale, H., Volkenandt, T., Wang, Y., Gao, J., Lu, T., Sun, K., Ritchie, R.O., & Shahani, A.J. (23 January 2020). Multi‐Step Crystallization of Self‐Organized Spiral Eutectics. Small (1906146). https://doi.org/10.1002/smll.201906146
- Discipline:
- Engineering
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- Creator:
- Wang, Yi and Hendy, Ingrid L.
- Description:
- The dataset contains bulk sedimentary d15N, TOC, and TN data measured every 2 mm on the core SPR0901-03KC. Flood and turbidite layers are shaded with blue and orange in the files. and This work is supported by NSF OCE-1304327.
- Keyword:
- d15N, total organic carbon, nitrogen isotopes, SPR0901-03KC, and Santa Barbara Basin
- Citation to related publication:
- Wang, Y. , Hendy, I. L. and Thunell, R. (2019), Local and remote forcing of denitrification in the Northeast Pacific for the last 2000 years. Paleoceanography and Paleoclimatology. Volume 34, issue 8, pages 1517-1533. https://doi.org/10.1029/2019PA003577
- Discipline:
- Science
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- Creator:
- Jialei Zhu and Joyce E. Penner
- Description:
- The dataset contains the Fortran programs applied in the latest CESM/IMPACT model as well as the data created from this model, which are used in the referenced paper.
- Keyword:
- Second organic aerosol, Radiative effect, and Cirrus cloud
- Citation to related publication:
- Zhu, J and Penner, J. E.: Indirect effects of secondary organic aerosol on cirrus clouds, (2019), Journal of Geophysical Research: Atmospheres, https://doi.org/10.1029/2019JD032233
- Discipline:
- Science
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- Creator:
- Huang, Yihe (University of Michigan); De Barros, Louis (Université Côte d’Azur)
- Description:
- Numerous small and moderate injection-induced earthquakes have been recorded in North America, Europe and Asia. Here we present a detailed analysis about microearthquakes in an in-situ injection-induced earthquake experiment, which provides an unprecedented opportunity to investigate the mechanisms of induced earthquakes. Our analysis illuminates meter-scale earthquake sources distributed in a network of preexisting rock fractures. The majority of induced earthquakes in our analysis happened when injection pressure reached a peak, indicating a direct response of rock fractures to fluid pressure perturbation. But the relatively low ratio of stress drop to crustal strength reveals that a very small fraction of the crustal shear strength is released by earthquakes, supporting the previous notion that fluid injection induces large aseismic deformation during the experiment. and Citation for dataset: Huang, Y., De Barros, L. (2019). Seismograms of earthquake pairs in the injection experiment [Data set]. University of Michigan - Deep Blue.
- Keyword:
- Induced seismicity
- Citation to related publication:
- Huang, Y., De Barros, L., Cappa, F. (2019). Illuminating the Rupturing of Microseismic Sources in an Injection‐Induced Earthquake Experiment. Geophysical Research Letters, 46(16), 9563-9572. https://doi.org/10.1029/2019GL083856
- Discipline:
- Science
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- Creator:
- Lim, Hongki and Dewaraja, Yuni K.
- Description:
- Internally administered targeted radionuclide therapy (TRT) with radio-labelled targeting molecules that deliver cytotoxic radiation to tumor has been used successfully to treat multiple cancers. Lu-177, used increasingly in TRT, emits both beta particles that deliver the therapeutic effect. FDA recently approved a fixed activity (4 cycles of 7.4 GBq/cycle as in NETTER -1) administered every 8 weeks. With the patient studies under this treatment, we collected CT images and corresponding volume of interest (organs, lesions) contours.
- Keyword:
- Lu-177, CT, Segmentation, Organ, Tumor, Label
- Discipline:
- Health Sciences
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- Creator:
- Basile, Samantha, Lin, Xin, and Keppel-Aleks, Gretchen
- Description:
- Files contain the atmospheric CO2 mole fraction responses to land flux type (HRcasa, HRcorpse, HRmimics) and land flux region (latband variable). Land flux regions are categorized as: Northern Hemisphere high latitudes (NHL; 61 to 90°N), midlatitudes (NML; 24 to 60°N), tropics (NT; 1 to 23°N), Southern Hemisphere tropics (ST; 0 to 23°S), and extratropics (SE; 24 to 90°S). See the README file for how these land flux region definitions relate to the file's latband variable. and To cite dataset: Basile, S., Lin, X., Keppel-Aleks, G. (2019). Simulated CO2 dataset using the atmospheric transport model GEOSChem v12.0.0: Response to regional land carbon fluxes [Data set]. University of Michigan - Deep Blue. https://doi.org/10.7302/xjzc-xy05
- Keyword:
- carbon dioxide, soil heterotrophic respiration, GEOSChem, HR, CO2, CASA-CNP, CORPSE, and MIMICS
- Discipline:
- Science
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- Creator:
- Zhu, Jialei and Penner, Joyce E.
- Description:
- The dataset contains the Fortran programs applied in the latest CESM/IMPACT model as well as the data created from this model, which are used in the referenced paper.
- Keyword:
- Organic nucleation, CESM/IMPACT, and SOA
- Citation to related publication:
- Zhu, J. and Penner, J. E.: Global modelling of secondary organic aerosol (SOA) with organic nucleation, (2019), Journal of Geophysical Research: Atmospheres, 124, 8260– 8286, https://doi.org/10.1029/2019JD030414
- Discipline:
- Science