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Holographic microscopy

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https://www.readbyqxmd.com/read/29044431/computational-imaging-of-sperm-locomotion
#1
Mustafa Ugur Daloglu, Aydogan Ozcan
Not only essential for scientific research, but also in the analysis of male fertility and for animal husbandry, sperm tracking and characterization techniques have been greatly benefiting from computational imaging. Digital image sensors, in combination with optical microscopy tools and powerful computers, have enabled the use of advanced detection and tracking algorithms that automatically map sperm trajectories and calculate various motility parameters across large data sets. Computational techniques are driving the field even further, facilitating the development of unconventional sperm imaging and tracking methods that do not rely on standard optical microscopes and objective lenses, which limit the field of view and volume of the semen sample that can be imaged...
August 1, 2017: Biology of Reproduction
https://www.readbyqxmd.com/read/29041487/3d-image-distortion-problem-in-digital-in-line-holographic-microscopy-and-its-effective-solution
#2
Heejung Lee, Philjun Jeon, Dugyoung Kim
Digital in-line holographic microscopy (DIHM) has attracted attention because of its simple but powerful three-dimensional (3D) imaging capability. To improve the spatial resolution, 3D image reconstruction algorithms use numerical magnification, which generates distortions in the generated images. We propose a method to overcome this problem by using the simple relation between the object and image positions in 3D space. Several holograms were taken while translating a resolution target at different axial positions by a motorized stage...
September 4, 2017: Optics Express
https://www.readbyqxmd.com/read/29041477/towards-a-holographic-approach-to-spherical-aberration-correction-in-scanning-transmission-electron-microscopy
#3
Vincenzo Grillo, Amir H Tavabi, Emrah Yucelen, Peng-Han Lu, Federico Venturi, Hugo Larocque, Lei Jin, Aleksei Savenko, Gian Carlo Gazzadi, Roberto Balboni, Stefano Frabboni, Peter Tiemeijer, Rafal E Dunin-Borkowski, Ebrahim Karimi
Recent progress in phase modulation using nanofabricated electron holograms has demonstrated how the phase of an electron beam can be controlled. In this paper, we apply this concept to the correction of spherical aberration in a scanning transmission electron microscope and demonstrate an improvement in spatial resolution. Such a holographic approach to spherical aberration correction is advantageous for its simplicity and cost-effectiveness.
September 4, 2017: Optics Express
https://www.readbyqxmd.com/read/29041474/coherent-noise-reduction-in-digital-holographic-microscopy-by-averaging-multiple-holograms-recorded-with-a-multimode-laser
#4
Feng Pan, Lizhi Yang, Wen Xiao
In digital holographic microscopy (DHM), it is undesirable to observe coherent noise in the reconstructed images. The sources of the noise are mainly the parasitic interference fringes caused by multiple reflections and the speckle pattern caused by the optical scattering on the object surface. Here we propose a noise reduction approach in DHM by averaging multiple holograms recorded with a multimode laser. Based on the periodicity of the temporal coherence of a multimode semiconductor laser, we acquire a series of holograms by changing the optical path length difference between the reference beam and object beam...
September 4, 2017: Optics Express
https://www.readbyqxmd.com/read/29041395/compact-and-stable-real-time-dual-wavelength-digital-holographic-microscopy-with-a-long-working-distance-objective
#5
Rongli Guo, Fan Wang
We propose a compact dual wavelength digital holographic Microscopy (DHM) based on a long working distance objective, which enabling quantitative phase imaging of opaque samples with extended measurement range in one shot. The compactness of the configuration is achieved by constructing a miniature modified Michelson interferometer between the objective and the sample, and as a result it provides higher temporal stability than conventional dual wavelength DHM. In the setup, the propagation directions of two reference beams of different wavelengths can be independently adjusted, and thus two off axis interferograms having orthogonal fringe directions can be simultaneously captured through a monochrome CCD camera...
October 2, 2017: Optics Express
https://www.readbyqxmd.com/read/29041325/spatial-mode-multiplexing-using-volume-holographic-gratings
#6
Sunil Vyas, Po-Hao Wang, Yuan Luo
We experimentally demonstrate spatial mode multiplexing of optical beams using multiplexed volume holographic gratings (MVGHs) formed in phenanthrenquinone-poly (methyl methacrylate) (PQ-PMMA) photopolymer. Multiple spatial modes of Laguerre-Gaussian (LG) beams are recorded at the same pupil area of a volume hologram resulting in MVHGs, for simultaneous reconstruction of spatial modes. In addition, a helical phase beam, a non-diffracting beam with conical phase profile, and a parabolic non-diffracting beam with cubic phase profile have also been simultaneously recorded and reconstructed from MVHGs...
October 2, 2017: Optics Express
https://www.readbyqxmd.com/read/29041134/depth-filtering-in-common-path-digital-holographic-microscopy
#7
Markus Finkeldey, Lena Göring, Carsten Brenner, Martin Hofmann, Nils C Gerhardt
We demonstrate a method to select different layers in a sample using a low coherent gating approach combined with a stable common-path quantitative phase imaging microscopy setup. The depth-filtering technique allows us to suppress the negative effects generated by multiple interference patterns of overlaying optical interfaces in the sample. It maintains the compact and stable common-path setup, while enabling images with a high phase sensitivity and acquisition speed. We use a holographic microscope in reflective geometry with a non-tunable low coherence light source...
August 7, 2017: Optics Express
https://www.readbyqxmd.com/read/28990642/quantitative-phase-microscopy-for-evaluation-of-intestinal-inflammation-and-wound-healing-utilizing-label-free-biophysical-markers
#8
REVIEW
Dominik Bettenworth, Arne Bokemeyer, Christopher Poremba, Nik Sheng Ding, Steffi Ketelhut, Philipp Lenz, Björn Kemper
Inflammatory bowel diseases (IBD) are inflammatory disorders of the gastrointestinal tract characterized by a chronic relapsing disease course. As uncontrolled intestinal inflammation can result in severe disease complications, recent treatment targets of IBD evolved toward seeking the absence of mucosal and histological inflammation. However, this approach requires adequate histological evaluation of IBD disease activity. The diagnostic challenge of histological examination of intestinal inflammation is documented by the multitude of proposed histological scoring systems...
October 9, 2017: Histology and Histopathology
https://www.readbyqxmd.com/read/28979841/evaluation-of-the-metastatic-potential-of-malignant-cells-by-image-processing-of-digital-holographic-microscopy-data
#9
Violeta L Calin, Mona Mihailescu, Eugen I Scarlat, Alexandra V Baluta, Daniel Calin, Eugenia Kovacs, Tudor Savopol, Mihaela G Moisescu
The cell refractive index has been proposed as a putative cancer biomarker of great potential, being correlated with cell content and morphology, cell division rate and membrane permeability. We used digital holographic microscopy to compare the refractive index and dry mass density of two B16 murine melanoma sublines of different metastatic potential. Using statistical methods, the distribution of phase shifts within the reconstructed quantitative phase images was analyzed by the method of bimodality coefficients...
October 2017: FEBS Open Bio
https://www.readbyqxmd.com/read/28957245/field-induced-lifetime-enhancement-of-photorefractive-gratings-in-a-mn-fe-ktn-crystal
#10
Qieni Lu, Bihua Li, Zhen Li, Baozhen Ge
We report the lifetime enhancement of light-induced refractive index grating by applying a bias field during writing. In comparison with the lifetime of about 10 hours of the photorefractive grating prepared without a bias field, the lifetime of the grating with a 4  kV/cm bias field can be prolonged to 7.5 years, which is obtained from the dynamic behavior of grating visualized and monitored with digital holographic microscopy. The higher the bias field is applied, the longer the dark decay time of grating can be achieved...
July 1, 2017: Optics Letters
https://www.readbyqxmd.com/read/28957063/compact-surface-plasmon-holographic-microscopy-for-near-field-film-mapping
#11
Jiwei Zhang, Siqing Dai, Chaojie Ma, Jianglei Di, Jianlin Zhao
We develop a compact objective-coupling surface plasmon holographic microscopy with a common-path configuration by introducing a Wollaston prism. Through off-axis hologram recording and numerical reconstruction, amplitude- and phase-contrast surface plasmon resonance (SPR) images can be obtained simultaneously. Based on the four-layer SPR model, the thin film thickness distribution in near field can be mapped unambiguously using a novel demodulation method without a priori knowledge. The technique demonstrates nondestructive and full-field measurement capabilities with sub-nanometer resolution theoretically...
September 1, 2017: Optics Letters
https://www.readbyqxmd.com/read/28947803/observation-of-nanoscale-magnetic-fields-using-twisted-electron-beams
#12
Vincenzo Grillo, Tyler R Harvey, Federico Venturi, Jordan S Pierce, Roberto Balboni, Frédéric Bouchard, Gian Carlo Gazzadi, Stefano Frabboni, Amir H Tavabi, Zi-An Li, Rafal E Dunin-Borkowski, Robert W Boyd, Benjamin J McMorran, Ebrahim Karimi
Electron waves give an unprecedented enhancement to the field of microscopy by providing higher resolving power compared to their optical counterpart. Further information about a specimen, such as electric and magnetic features, can be revealed in electron microscopy because electrons possess both a magnetic moment and charge. In-plane magnetic structures in materials can be studied experimentally using the effect of the Lorentz force. On the other hand, full mapping of the magnetic field has hitherto remained challenging...
September 25, 2017: Nature Communications
https://www.readbyqxmd.com/read/28940694/sterol-synthesis-and-cell-size-distribution-under-oscillatory-growth-conditions-in-saccharomyces-cerevisiae-scale-down-cultivations
#13
Anna-Maria Marbà-Ardébol, Anika Bockisch, Peter Neubauer, Stefan Junne
Physiologic responses of yeast to oscillatory environments as they appear in the liquid phase in large-scale bioreactors were studied in the past. So far, however, the impact on the sterol household and intracellular regulation remains to be investigated. Since oxygen is a co-factor in several reaction steps within the sterol metabolism, changes in oxygen availability, as it occurs in aerated bioreactors of production scales, might have an influence on the regulation and incorporation of free sterols into the cells' lipid layer...
September 21, 2017: Yeast
https://www.readbyqxmd.com/read/28933990/influence-of-salinomycin-treatment-on-division-and-movement-of-individual-cancer-cells-cultured-in-normoxia-or-hypoxia-evaluated-with-time-lapse-digital-holographic-microscopy
#14
Sofia Kamlund, Daniel Strand, Birgit Janicke, Kersti Alm, Stina Oredsson
Most studies on new cancer drugs are based on population-derived data, where the absence of response of a small population may pass unnoticed. Thus, individual longitudinal tracking of cells is important for the future development of efficient cancer treatments. We have used digital holographic microscopy to track individual JIMT-1 human breast cancer cells and L929 mouse fibroblast cultivated in normoxia or hypoxia. In addition, JIMT-1 cells were treated with salinomycin, a cancer stem cell targeting compound...
September 21, 2017: Cell Cycle
https://www.readbyqxmd.com/read/28916149/wavelet-based-tracking-of-bacteria-in-unreconstructed-off-axis-holograms
#15
Zach Marin, J Kent Wallace, Jay Nadeau, Andre Khalil
We propose an automated wavelet-based method of tracking particles in unreconstructed off-axis holograms to provide rough estimates of the presence of motion and particle trajectories in digital holographic microscopy (DHM) time series. The wavelet transform modulus maxima segmentation method is adapted and tailored to extract Airy-like diffraction disks, which represent bacteria, from DHM time series. In this exploratory analysis, the method shows potential for estimating bacterial tracks in low-particle-density time series, based on a preliminary analysis of both living and dead Serratia marcescens, and for rapidly providing a single-bit answer to whether a sample chamber contains living or dead microbes or is empty...
September 13, 2017: Methods: a Companion to Methods in Enzymology
https://www.readbyqxmd.com/read/28894326/calcite-dissolution-rate-spectra-measured-by-in-situ-digital-holographic-microscopy
#16
Alexander S Brand, Pan Feng, Jeffrey W Bullard
Digital holographic microscopy in reflection mode is used to track in situ, real-time nanoscale topography evolution of cleaved (104) calcite surfaces exposed to flowing or static deionized water. The method captures full-field holograms of the surface at frame rates of up to 12.5 s(-1). Numerical reconstruction provides 3D surface topography with vertical resolution of a few nanometers and enables measurement of time-dependent local dissolution fluxes. A statistical distribution, or spectrum, of dissolution rates is generated by sampling multiple area domains on multiple crystals...
September 2017: Geochimica et Cosmochimica Acta
https://www.readbyqxmd.com/read/28864356/lensless-digital-holographic-microscopy-and-its-applications-in-biomedicine-and-environmental-monitoring
#17
REVIEW
Yichen Wu, Aydogan Ozcan
Optical compound microscope has been a major tool in biomedical imaging for centuries. Its performance relies on relatively complicated, bulky and expensive lenses and alignment mechanics. In contrast, the lensless microscope digitally reconstructs microscopic images of specimens without using any lenses, as a result of which it can be made much smaller, lighter and lower-cost. Furthermore, the limited space-bandwidth product of objective lenses in a conventional microscope can be significantly surpassed by a lensless microscope...
August 29, 2017: Methods: a Companion to Methods in Enzymology
https://www.readbyqxmd.com/read/28846747/distinctive-behaviour-of-live-biopsy-derived-carcinoma-cells-unveiled-using-coherence-controlled-holographic-microscopy
#18
Břetislav Gál, Miroslav Veselý, Jana Čolláková, Marta Nekulová, Veronika Jůzová, Radim Chmelík, Pavel Veselý
Head and neck squamous cell carcinoma is one of the most aggressive tumours and is typically diagnosed too late. Late diagnosis requires an urgent decision on an effective therapy. An individualized test of chemosensitivity should quickly indicate the suitability of chemotherapy and radiotherapy. No ex vivo chemosensitivity assessment developed thus far has become a part of general clinical practice. Therefore, we attempted to explore the new technique of coherence-controlled holographic microscopy to investigate the motility and growth of live cells from a head and neck squamous cell carcinoma biopsy...
2017: PloS One
https://www.readbyqxmd.com/read/28841322/dissolution-kinetics-of-cubic-tricalcium-aluminate-measured-by-digital-holographic-microscopy
#19
Alexander S Brand, Jeffrey W Bullard
In situ digital holographic microscopy is used to characterize the dissolution flux of polycrystalline cubic tricalcium aluminate (C3A-c). The surface dissolves at rates that vary considerably with time and spatial location. This implies a statistical distribution of fluxes, but an approximately steady-state median rate was obtained by using flowing solutions and by reducing the water activity in the solution. The dissolution flux from highly crystalline C3A-c depends on the water activity raised to an empirically derived exponent of 5...
September 7, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28836416/automated-classification-of-cell-morphology-by-coherence-controlled-holographic-microscopy
#20
Lenka Strbkova, Daniel Zicha, Pavel Vesely, Radim Chmelik
In the last few years, classification of cells by machine learning has become frequently used in biology. However, most of the approaches are based on morphometric (MO) features, which are not quantitative in terms of cell mass. This may result in poor classification accuracy. Here, we study the potential contribution of coherence-controlled holographic microscopy enabling quantitative phase imaging for the classification of cell morphologies. We compare our approach with the commonly used method based on MO features...
August 2017: Journal of Biomedical Optics
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