scholarly journals Toward a scalable framework for reproducible processing of volumetric, nanoscale neuroimaging datasets

GigaScience ◽  
2020 ◽  
Vol 9 (12) ◽  
Author(s):  
Erik C Johnson ◽  
Miller Wilt ◽  
Luis M Rodriguez ◽  
Raphael Norman-Tenazas ◽  
Corban Rivera ◽  
...  

Abstract Background Emerging neuroimaging datasets (collected with imaging techniques such as electron microscopy, optical microscopy, or X-ray microtomography) describe the location and properties of neurons and their connections at unprecedented scale, promising new ways of understanding the brain. These modern imaging techniques used to interrogate the brain can quickly accumulate gigabytes to petabytes of structural brain imaging data. Unfortunately, many neuroscience laboratories lack the computational resources to work with datasets of this size: computer vision tools are often not portable or scalable, and there is considerable difficulty in reproducing results or extending methods. Results We developed an ecosystem of neuroimaging data analysis pipelines that use open-source algorithms to create standardized modules and end-to-end optimized approaches. As exemplars we apply our tools to estimate synapse-level connectomes from electron microscopy data and cell distributions from X-ray microtomography data. To facilitate scientific discovery, we propose a generalized processing framework, which connects and extends existing open-source projects to provide large-scale data storage, reproducible algorithms, and workflow execution engines. Conclusions Our accessible methods and pipelines demonstrate that approaches across multiple neuroimaging experiments can be standardized and applied to diverse datasets. The techniques developed are demonstrated on neuroimaging datasets but may be applied to similar problems in other domains.

2019 ◽  
Author(s):  
Erik C. Johnson ◽  
Miller Wilt ◽  
Luis M. Rodriguez ◽  
Raphael Norman-Tenazas ◽  
Corban Rivera ◽  
...  

ABSTRACTEmerging neuroimaging datasets (collected through modalities such as Electron Microscopy, Calcium Imaging, or X-ray Microtomography) describe the location and properties of neurons and their connections at unprecedented scale, promising new ways of understanding the brain. These modern imaging techniques used to interrogate the brain can quickly accumulate gigabytes to petabytes of structural brain imaging data. Unfortunately, many neuroscience laboratories lack the computational expertise or resources to work with datasets of this size: computer vision tools are often not portable or scalable, and there is considerable difficulty in reproducing results or extending methods. We developed an ecosystem of neuroimaging data analysis pipelines that utilize open source algorithms to create standardized modules and end-to-end optimized approaches. As exemplars we apply our tools to estimate synapse-level connectomes from electron microscopy data and cell distributions from X-ray microtomography data. To facilitate scientific discovery, we propose a generalized processing framework, that connects and extends existing open-source projects to provide large-scale data storage, reproducible algorithms, and workflow execution engines. Our accessible methods and pipelines demonstrate that approaches across multiple neuroimaging experiments can be standardized and applied to diverse datasets. The techniques developed are demonstrated on neuroimaging datasets, but may be applied to similar problems in other domains.


2021 ◽  
Author(s):  
Tinashe M. Tapera ◽  
Matthew Cieslak ◽  
Max Bertolero ◽  
Azeez Adebimpe ◽  
Geoffrey K. Aguirre ◽  
...  

ABSTRACTThe recent and growing focus on reproducibility in neuroimaging studies has led many major academic centers to use cloud-based imaging databases for storing, analyzing, and sharing complex imaging data. Flywheel is one such database platform that offers easily accessible, large-scale data management, along with a framework for reproducible analyses through containerized pipelines. The Brain Imaging Data Structure (BIDS) is a data storage specification for neuroimaging data, but curating neuroimaging data into BIDS can be a challenging and time-consuming task. In particular, standard solutions for BIDS curation are not designed for use on cloud-based systems such as Flywheel. To address these challenges, we developed “FlywheelTools”, a software toolbox for reproducible data curation and manipulation on Flywheel. FlywheelTools includes two elements: fw-heudiconv, for heuristic-driven curation of data into BIDS, and flaudit, which audits and inventories projects on Flywheel. Together, these tools accelerate reproducible neuroscience research on the widely used Flywheel platform.


Author(s):  
R.G. Frederickson ◽  
R.G. Ulrich ◽  
J.L. Culberson

Metallic cobalt acts as an epileptogenic agent when placed on the brain surface of some experimental animals. The mechanism by which this substance produces abnormal neuronal discharge is unknown. One potentially useful approach to this problem is to study the cellular and extracellular distribution of elemental cobalt in the meninges and adjacent cerebral cortex. Since it is possible to demonstrate the morphological localization and distribution of heavy metals, such as cobalt, by correlative x-ray analysis and electron microscopy (i.e., by AEM), we are using AEM to locate and identify elemental cobalt in phagocytic meningeal cells of young 80-day postnatal opossums following a subdural injection of cobalt particles.


2020 ◽  
Vol 637 ◽  
pp. A52 ◽  
Author(s):  
R. Nanni ◽  
R. Gilli ◽  
C. Vignali ◽  
M. Mignoli ◽  
A. Peca ◽  
...  

We present the X-ray source catalog for the ∼479 ks Chandra exposure of the SDSS J1030+0524 field, which is centered on a region that shows the best evidence to date of an overdensity around a z > 6 quasar, and also includes a galaxy overdensity around a Compton-thick Fanaroff-Riley type II (FRII) radio galaxy at z = 1.7. Using wavdetect for initial source detection and ACIS Extract for source photometry and significance assessment, we create preliminary catalogs of sources that are detected in the full (0.5−7.0 keV), soft (0.5−2.0 keV), and hard (2−7 keV) bands, respectively. We produce X-ray simulations that mirror our Chandra observation to filter our preliminary catalogs and achieve a completeness level of > 91% and a reliability level of ∼95% in each band. The catalogs in the three bands are then matched into a final main catalog of 256 unique sources. Among them, 244, 193, and 208 are detected in the full, soft, and hard bands, respectively. The Chandra observation covers a total area of 335 arcmin2 and reaches flux limits over the central few square arcmins of ∼3 × 10−16, 6 × 10−17, and 2 × 10−16 erg cm−2 s−1 in the full, soft, and hard bands, respectively This makes J1030 field the fifth deepest extragalactic X-ray survey to date. The field is part of the Multiwavelength Survey by Yale-Chile (MUSYC), and is also covered by optical imaging data from the Large Binocular Camera (LBC) at the Large Binocular Telescope (LBT), near-infrared imaging data from the Canada France Hawaii Telescope WIRCam (CFHT/WIRCam), and Spitzer IRAC. Thanks to its dense multi-wavelength coverage, J1030 represents a legacy field for the study of large-scale structures around distant accreting supermassive black holes. Using a likelihood ratio analysis, we associate multi-band (r, z, J, and 4.5 μm) counterparts for 252 (98.4%) of the 256 Chandra sources, with an estimated reliability of 95%. Finally, we compute the cumulative number of sources in each X-ray band, finding that they are in general agreement with the results from the Chandra Deep Fields.


2016 ◽  
Vol 16 (4) ◽  
pp. 3705-3709 ◽  
Author(s):  
Zhi-Wen Nie ◽  
Cheng-Hui Zeng ◽  
Gang Xie ◽  
Sheng-Liang Zhong

Homogeneously doped Yb3+ and Er3+ cerium-based coordination polymer (CP) microspheres have been successfully synthesized on a large scale through a simple solvothermal route with 2, 5-pyridinedicarboxylic acid (2, 5-H2PDC) as the organic linker. CeO2:Yb3+, Er3+ porous microspheres were obtained by annealing the corresponding CP microspheres at 600 °C for 4 h under atmospheric pressure. These as-prepared products were characterized by Powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), energy-dispersion X-ray (EDX) spectroscopy, Thermogravimetric (TG) and derivative thermogravimetric (DTG) analysis. The room temperature upconversion luminescent spectra of the as-prepared microspheres were carried out by 980 nm NIR light excitation. Interestingly, Yb3+ and Er3+ codoped CP microspheres give a single-band emission centered at 673 nm, while the CeO2:Yb3+, Er3+ microspheres give emission in green and red region, with red being the dominant emission. The emission intensity of the CeO2:Yb3+, Er3+ microspheres were much stronger than that of the Yb3+ and Er3+ codoped CP microspheres.


2006 ◽  
Vol 05 (04n05) ◽  
pp. 479-485
Author(s):  
C. W. LAI ◽  
X. Y. ZHANG ◽  
H. C. ONG ◽  
J. Y. DAI ◽  
H. L. W. CHAN

Large-scale single crystalline In 2 O 3 nanowires were successfully synthesized on anodic alumina membranes by a simple thermal evaporation method at 570°C. X-ray diffraction, transmission electron microscopy, and scanning electron microscopy studies revealed the formation of single crystalline In 2 O 3 nanowires with diameters of 50–100 nm and lengths of up to a few hundreds of micrometers. Cathodeluminescence study revealed existence of oxygen vacancies evidenced by a strong and broad emission at 470 nm with a shoulder at 400 nm. The growth mechanism of the nanostructures is also discussed.


2012 ◽  
Vol 502 ◽  
pp. 164-168
Author(s):  
Ling Xu ◽  
Han Mei Hu ◽  
Hai Yan Xu

Novel mace-like (wolf-teeth clubs) CdS nanostructures were successfully prepared on a large scale using CdCl2•2.5H2O and NH2CSNH2 as starting materials through a convenient mixed-solvothermal route. The as-synthesized products were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectrometry (EDX), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and UV-visible absorption spectroscopy. The experimental results reveal that the morphology of CdS products was greatly affected by the volume ratio of anhydrous ethanol and distilled water. The possible mechanism for the formation of mace-like CdS nanostructures is simply discussed.


Author(s):  
Nitesh Yadav

Abstract: This review focuses on different imaging techniques such as MRI. This survey identifies a different approach with better accuracy for tumor detection. This further includes the image processing method. In most applications, machine learning shows better performance than manual segmentation of the brain tumors from MRI images as it is a difficult and timeconsuming task. For fast and better computational results, radiology used a different approach with MRI, CT-scan, X-ray, and PET. Furthermore, summarizing the literature, this paper also provides a critical evaluation of the surveyed literature which reveals new facets of research. Keywords: Brain tumor, data mining techniques, filtering techniques, MRI, classifiers, feature selection.


2021 ◽  
Author(s):  
Juan Felipe Moreno Manrique ◽  
Parker R. Voit ◽  
Kathryn E. Windsor ◽  
Aamuktha R. Karla ◽  
Sierra R. Rodriguez ◽  
...  

While electron microscopy represents the gold standard for detection of synapses, a number of limitations prevent its broad applicability. A key method for detecting synapses is immunostaining for markers of pre- and post-synaptic proteins, which can infer a synapse based upon the apposition of the two markers. While immunostaining and imaging techniques have improved to allow for identification of synapses in tissue, analysis and identification of these appositions are not facile, and there has been a lack of tools to accurately identify these appositions. Here, we delineate a macro that uses open-source and freely available ImageJ or FIJI for analysis of multichannel, z-stack confocal images. With use of a high magnification with a high NA objective, we outline two methods to identify puncta in either sparsely or densely labeled images. Puncta from each channel are used to eliminate non-apposed puncta and are subsequently linked with their cognate from the other channel. These methods are applied to analysis of a presynaptic marker, bassoon, with two different postsynaptic markers, gephyrin and N-methyl-d-aspartate (NMDA) receptor subunit 1 (NR1). Using gephyrin as an inhibitory, postsynaptic scaffolding protein, we identify inhibitory synapses in basolateral amygdala, central amygdala, arcuate and the ventromedial hypothalamus. Systematic variation of the settings identify the parameters most critical for this analysis. Identification of specifically overlapping puncta allows for correlation of morphometry data between each channel. Finally, we extend the analysis to only examine puncta overlapping with a cytoplasmic marker of specific cell types, a distinct advantage beyond electron microscopy. Bassoon puncta are restricted to virally transduced, pedunculopontine tegmental neuron (PPN) axons expressing yellow fluorescent protein. NR1 puncta are restricted to tyrosine hydroxylase labeled dopaminergic neurons of the substantia nigra pars compacta (SNc). The macro identifies bassoon-NR1 overlap throughout the image, or those only restricted to the PPN-SNc connections. Thus, we have extended the available analysis tools that can be used to study synapses in situ. Our analysis code is freely available and open-source allowing for further innovation. 


2020 ◽  
Vol 10 (3) ◽  
pp. 5648-5655

Single phase ZnO nanostructures were synthesized by simple and low temperature solvothermal process from two different alkaline sources; Potassium hydroxide (KOH) and Sodium hydroxide (NaOH) with zinc acetate dihydrate (Zn(CH3COO)2∙2H2O) as precursor. This facile and rapid synthesis technique achieve high purity of Zinc oxide (ZnO) nanostructures on large scale negating the use of complex and high temperature routes. The synthesized particles were characterized by X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM), Transmission Electron Microscopy (TEM), Energy-dispersive X-ray spectroscopy (EDX), Fourier Transform Infrared (FT-IR) Spectroscopy, Ultraviolet Visible (UV-Vis) spectroscopy and Brunauer-Emmett-Teller (BET) analysis. ZnO synthesized using KOH and NaOH exhibit wurtzite hexagonal and flake-like nanostructures with average crystallite size of 11.0 nm and 14.9 nm respectively. Surface area of 59.50 m2/g and 31.43 m2/g were determined for KOH and NaOH sources respectively. The optical absorption spectra of the two samples showed absorption bands of 367.70 and 365.30 nm. The results showed the effect of alkaline sources on the surface morphology, structural and optical properties of ZnO.


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