scholarly journals Design, Calibration, and Application of a Robust, Cost-Effective, and High-Resolution Lensless Holographic Microscope

Sensors ◽  
2022 ◽  
Vol 22 (2) ◽  
pp. 553
Author(s):  
Jose Angel Picazo-Bueno ◽  
Karina Trindade ◽  
Martin Sanz ◽  
Vicente Micó
Keyword(s):  
High Resolution ◽  
Point Of Care ◽  
Cost Effective ◽  
Complete Characterization ◽  
Field Of View ◽  
Complete Analysis ◽  
Optical Parameters ◽  
Remote Areas ◽  
Quality Imaging

Lensless holographic microscope (LHM) is an emerging very promising technology that provides high-quality imaging and analysis of biological samples without utilizing any lens for imaging. Due to its small size and reduced price, LHM can be a very useful tool for the point-of-care diagnosis of diseases, sperm assessment, or microfluidics, among others, not only employed in advanced laboratories but also in poor and/or remote areas. Recently, several LHMs have been reported in the literature. However, complete characterization of their optical parameters remains not much presented yet. Hence, we present a complete analysis of the performance of a compact, reduced cost, and high-resolution LHM. In particular, optical parameters such as lateral and axial resolutions, lateral magnification, and field of view are discussed into detail, comparing the experimental results with the expected theoretical values for different layout configurations. We use high-resolution amplitude and phase test targets and several microbeads to characterize the proposed microscope. This characterization is used to define a balanced and matched setup showing a good compromise between the involved parameters. Finally, such a microscope is utilized for visualization of static, as well as dynamic biosamples.

X-ray topo-tomography studies of linear dislocations in silicon single crystals

2018 ◽  
Vol 51 (6) ◽  
pp. 1616-1622 ◽  
Author(s):  
Victor Asadchikov ◽  
Alexey Buzmakov ◽  
Felix Chukhovskii ◽  
Irina Dyachkova ◽  
Denis Zolotov ◽  
...  
Keyword(s):  
Numerical Analysis ◽  
High Resolution ◽  
Single Crystals ◽  
Complete Characterization ◽  
Reconstruction Technique ◽  
Algebraic Reconstruction Technique ◽  
X Ray ◽  
Laboratory Setup ◽  
Simultaneous Algebraic Reconstruction Technique

This article describes complete characterization of the polygonal dislocation half-loops (PDHLs) introduced by scratching and subsequent bending of an Si(111) crystal. The study is based on the X-ray topo-tomography technique using both a conventional laboratory setup and the high-resolution X-ray image-detecting systems at the synchrotron facilities at KIT (Germany) and ESRF (France). Numerical analysis of PDHL images is performed using the Takagi–Taupin equations and the simultaneous algebraic reconstruction technique (SART) tomographic algorithm.

scholarly journals Point of care high resolution ultrasound in the evaluation of Bangladeshi women presenting to a breast care center

2017 ◽  
Vol 49 (1-2) ◽  
pp. 3-6
Author(s):  
Richard R Love ◽  
Syed Mozammel Hossain ◽  
James Woods ◽  
Sk Farid Uddin Ahmed ◽  
Moslema Parvin ◽  
...  
Keyword(s):  
High Resolution ◽  
Physical Examination ◽  
Point Of Care ◽  
Care Center ◽  
Breast Disease ◽  
Ultrasound Findings ◽  
Breast Condition ◽  
Breast Care

Background: Mammography and ultrasound examinations for diagnosis and staging of breast problems have been traditionally performed in specialized facilities, which circumstances are associated with increased costs and inconvenience for patients. Point of care or clinical office provision of high resolution ultrasound may allow addressing these equity barriers to health services, but there are limited data in Bangladesh about such practice and the associated quality of care.Objective: To ascertain the advantage of ultrasonogram in the diagnosis of breast disease and screening of breast cancer.Methods: From February through November 2014, 1085 women presented to the Amader Gram Breast Care Center in Khulna. In each of these women in addition to standard history and physical examination, a high resolution ultrasound scan was performed of both breasts. Standard clinical and ultrasound practice definitions of breast conditions were applied to each case by an specialist surgeon trained in breast sonology.Results: Two thirds of women had history, physical examination and ultrasound findings consistent with fibrocystic conditions. 12% had fibro adenomas, 5% inflammatory infectious conditions, 2% obvious or strongly suspected breast malignacy, and 1% had masses of uncertain nature. 3% had more than one abnormal breast condition and 3% had no breast abnormalities at all. The overwhelming majority of women benefitted from having ultrasound examination which contributed to prompt, definitive characterization of their breast conditions and which pictorial demonstration contributed to patient education about the clinical diagnosis.Conclusion: Point of care high resolution breast ultrasound can contribute favorably to quality and equity of care for Bangladeshi women with breast problems.Bang Med J (Khulna) 2016; 49 : 3-6

High-Resolution Observation of Twinning in Fe1-XS Crystals

1985 ◽  
Vol 43 ◽  
pp. 224-225 ◽  
Author(s):  
Thao A. Nguyen ◽  
Linn W. Hobbs ◽  
Peter R. Buseck
Keyword(s):  
High Resolution ◽  
Iron Sulfide ◽  
Optical Parameters ◽  
Planar Defects ◽  
Electrical And Magnetic Properties ◽  
Transmission Electron ◽  
Resolution Observation ◽  
Half Angle ◽  
Lattice Images

The ordering of iron vacancies in highly nonstoichiometric iron sulfide compounds (Fe1-xS, 0 ⩽ x ⩽ 0.125) at temperature below 425K give rise to at least two different superstructures and a number of possible planar defect configurations. These ordered iron vacancies and associated planar defects are believed to influence greatly the electrical and magnetic properties of Fe1-xS crystals. Extensive efforts, employing high resolution transmission electron microscopy, to characterize the ordering of iron vacancies and associated planar defects have been carried out by Nguyen and Hobbs, Pierce and Buseck, and Nakazawa, et al. In this paper we report the characterization of twin boundaries in iron sulfide crystal of composition nominally Fe9S10.Many beam lattice images of crushed synthetic Fe9S10 crystals were obtained in a top-entry JEM 200CX transmission electron microscope. Relevant electron optical parameters were Cs = 1.2mm; divergence half-angle α = 0.5mrad; and an objective aperture which allowed electron beams up to 5nm-1 to contribute to the final image.

Combination of high resolution melting (HRM) analysis and SSR molecular markers speeds up plum genotyping: case study genotyping the Greek plum GeneBank collection

2016 ◽  
Vol 15 (4) ◽  
pp. 366-375 ◽  
Author(s):  
Georgios Merkouropoulos ◽  
Ioannis Ganopoulos ◽  
Athanasios Tsaftaris ◽  
Ioannis Papadopoulos ◽  
Pavlina Drogoudi
Keyword(s):  
High Resolution ◽  
High Resolution Melting ◽  
Cost Effective ◽  
Ex Situ ◽  
Hrm Analysis ◽  
Prunus Salicina ◽  
Genebank Collection ◽  
Of Greece

AbstractIn a germplasm bank collection the conservation and characterization of genetic resources is a prerequisite in order to use the material in breeding projects aiming the creation of new cultivars. In the present study, 54 Prunus salicina domestica and Prunus domestica genotypes (including seven Greek cultivars), maintained in the ex situ National Genebank Collection of Greece, were classified using microsatellite (simple sequence repeat, SSR) markers on high resolution melting (HRM) analysis. The SSR primer pairs were chosen from the published literature as originally designed on Prunus species. This combined approach was used to genotype all plum accessions of the collection highlighting the benefits of either method (HRM and SSRs) for cultivar identification. Dendrograms for P. domestica and P. salicina and a combined one with all the genotypes assayed were produced. A total of 15 from the 19 P. domestica accessions analysed, including all the Greek accessions but ‘Avgati Skopelou’, were grouped into the same clade in the combined dendrogram, whereas the remaining four were dispersed into the P. salinica clades. Bayesian structure analysis confirmed that ‘Avgati Skopelou’ differs from the rest of the Greek plum cultivars since it was not grouped into the same cluster. The combination of HRM and SSRs, provided a considerably faster, cost-effective, closed-tube microsatellite genotyping method for molecular characterization of plum cultivars.

scholarly journals Wide-Field-of-View Longwave Camera for the Characterization of the Earth’s Outgoing Longwave Radiation

Sensors ◽  
2021 ◽  
Vol 21 (13) ◽  
pp. 4444
Author(s):  
Luca Schifano ◽  
Lien Smeesters ◽  
Francis Berghmans ◽  
Steven Dewitte
Keyword(s):  
Outgoing Longwave Radiation ◽  
Longwave Radiation ◽  
Cost Effective ◽  
Field Of View ◽  
Wide Field ◽  
Space Applications ◽  
Wide Field Of View ◽  
Camera Design ◽  
Effective Design

The measurement of the Earth’s Outgoing Longwave Radiation plays a key role in climate change monitoring. This measurement requires a compact wide-field-of-view camera, covering the 8–14 µm wavelength range, which is not commercially available. Therefore, we present a novel thermal wide-field-of-view camera optimized for space applications, featuring a field of view of 140° to image the Earth from limb to limb, while enabling a high spatial resolution of 4.455 km at nadir. Our cost-effective design comprises three germanium lenses, of which only one has a single aspherical surface. It delivers a very good image quality, as shown by the nearly-diffraction-limited performance. Radiative transfer simulations indicate excellent performance of our camera design, enabling an estimate of the broadband Outgoing Longwave Radiation with a random relative error of 4.8%.

Very High Resolution Analysis of the Dynamics of a Coronal Plasmoid

1994 ◽  
Vol 144 ◽  
pp. 593-596
Author(s):  
O. Bouchard ◽  
S. Koutchmy ◽  
L. November ◽  
J.-C. Vial ◽  
J. B. Zirker
Keyword(s):  
High Resolution ◽  
Solar Eclipse ◽  
Total Solar Eclipse ◽  
Field Of View ◽  
Small Field ◽  
High Resolution Analysis ◽  
Ccd Observations ◽  
Resolution Analysis ◽  
Very High ◽  
Small Field Of View

AbstractWe present the results of the analysis of a movie taken over a small field of view in the intermediate corona at a spatial resolution of 0.5“, a temporal resolution of 1 s and a spectral passband of 7 nm. These CCD observations were made at the prime focus of the 3.6 m aperture CFHT telescope during the 1991 total solar eclipse.

Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

1983 ◽  
Vol 41 ◽  
pp. 194-195
Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor
Keyword(s):  
High Resolution ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Structural Features ◽  
Sea Stars ◽  
High Resolution Tem ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

A High Resolution Scanning Microscope

1968 ◽  
Vol 26 ◽  
pp. 356-357
Author(s):  
A. V. Crewe ◽  
J. Wall ◽  
L. M. Welter
Keyword(s):  
High Resolution ◽  
Field Emission ◽  
Spherical Aberration ◽  
Focal Length ◽  
Spot Size ◽  
Emission Source ◽  
Field Of View ◽  
Scanning Microscope ◽  
Magnetic Lens ◽  
High Quality

A scanning microscope using a field emission source has been described elsewhere. This microscope has now been improved by replacing the single magnetic lens with a high quality lens of the type described by Ruska. This lens has a focal length of 1 mm and a spherical aberration coefficient of 0.5 mm. The final spot size, and therefore the microscope resolution, is limited by the aberration of this lens to about 6 Å.The lens has been constructed very carefully, maintaining a tolerance of + 1 μ on all critical surfaces. The gun is prealigned on the lens to form a compact unit. The only mechanical adjustments are those which control the specimen and the tip positions. The microscope can be used in two modes. With the lens off and the gun focused on the specimen, the resolution is 250 Å over an undistorted field of view of 2 mm. With the lens on,the resolution is 20 Å or better over a field of view of 40 microns. The magnification can be accurately varied by attenuating the raster current.

High-resolution electron microscopy of nanostructured materials

1995 ◽  
Vol 53 ◽  
pp. 172-173
Author(s):  
M. José-Yacamán
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Grain Boundaries ◽  
Nanostructured Materials ◽  
High Resolution Electron Microscopy ◽  
Hrem Image ◽  
Small Particles ◽  
Resolution Electron ◽  
Nanophase Materials

Electron microscopy is a fundamental tool in materials characterization. In the case of nanostructured materials we are looking for features with a size in the nanometer range. Therefore often the conventional TEM techniques are not enough for characterization of nanophases. High Resolution Electron Microscopy (HREM), is a key technique in order to characterize those materials with a resolution of ~ 1.7A. High resolution studies of metallic nanostructured materials has been also reported in the literature. It is concluded that boundaries in nanophase materials are similar in structure to the regular grain boundaries. That work therefore did not confirm the early hipothesis on the field that grain boundaries in nanostructured materials have a special behavior. We will show in this paper that by a combination of HREM image processing, and image calculations, it is possible to prove that small particles and coalesced grains have a significant surface roughness, as well as large internal strain.

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