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Task-specific uncertainty of areal surface texture measurement using structured illumination microscopyLi, Zhen 31 May 2023 (has links)
Surface quality plays a vital role in controlling the function performance of the workpiece. With the development of the measuring technique, areal surface measurement has been widely applied in the industry. However, estimating the uncertainty of areal surface measurement is still a challenge. Except for the metrological characteristics of the measurement system, measurement conditions should be considered for uncertainty evaluation.
The dissertation investigates the influence of measurement settings on surface measurement. A silver-plated surface, three different rough grinding surfaces, and three different rough cylindrical grinding surfaces were measured using structured illumination microscopy. The measurements were at the different objective lenses, vertical scanning interval, exposure time, and sample tilt. The results show that the measurement settings influence the non-measured points, measurement noise, and areal surface texture parameters. Therefore, according to the investigation, the sample tilt and exposure time should also be included in the uncertainty budget.
An approach was proposed to investigate the influence of non-measured points on the areal surface texture parameters. The relation between the non-measured points ratio and measurement settings was investigated, and how the areal surface texture parameters changed due to the non-measured points was studied. Moreover, an approach based on the metrological characteristic method was proposed to estimate the uncertainty due to the measurement noise. This method can be extended to the uncertainty evaluation due to other metrological characteristics. Additionally, an approach based on the Monte Carlo Method was proposed to estimate the measurement uncertainty due to different influences. This approach was verified as feasible in the practical measurement.
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Optical micro-manipulation in HIV-1 infected cells for improved HIV-1 treatment and diagnosisLugongolo, Masixole Yvonne 06 1900 (has links)
Laser application in the field of biological and medical sciences has significantly grown, thereby
strengthening the field of Biophotonics. Research conducted in Biophotonics focuses on the concept
of using light especially in the visible and near infrared regions of the electromagnetic radiation for
the evaluation of living systems. In this thesis new discoveries are presented about low level laser
therapy, optical trapping, transmission spectroscopy, luminescence spectroscopy and structured
illumination microscopy (SIM), displaying the impact each technique has on HIV infected cells. The
results showed that the irradiation of HIV-1 infected TZM-bl cells with low power red laser reduces
HIV-1 infection. The outcomes of this study further proved that when irradiation is used in
conjunction with efavirenz, an antiretroviral drug, HIV-1 infection could be reduced to undetectable
levels in TZM-bl cells. Through the coupling of transmission spectroscopy with optical trapping, and
separately, use of luminescence spectroscopy, label free diagnosis of HIV in infected cell samples
was achieved. This finding affirms that HIV-1 infection can be detected in a label free manner when
using laser based techniques. Furthermore, the photoluminescence spectrometer system was
employed to generate a decay curve, which was necessary so as to have some understanding on
lifetime of the luminescent signal in infected TZM-bl cells. Finally, in order to confirm that indeed
TZM-bl cells were infected, an established super-resolution microscopy system SIM was used to
detect HIV-1 infection in TZM-bl cells. Indeed in the infected cells viral molecules p24 and gp41
were detected through SIM, while they were not detected in uninfected cells. In future studies, super
resolution microscopy would be coupled to an optical trapping system in order to confirm that each
trapped cells is whether infected or uninfected so as to improve HIV diagnosis. / College of Science, Engineering and Technology / Ph. D. (Science, Engineering and Technology)
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Non-destructive evaluation of white striping and microbial spoilage of Broiler Breast Meat using structured-illumination reflectance imagingOlaniyi, Ebenezer O 08 August 2023 (has links) (PDF)
Manual inspection is a prevailing practice for quality assessment of poultry meat, but it is labor-intensive, tedious, and subjective. This thesis aims to assess the efficacy of an emerging structured illumination reflectance imaging (SIRI) technique with machine learning approaches for assessing WS and microbial spoilage in broiler breast meat. Broiler breast meat samples were imaged by an in house-assembled SIRI platform under sinusoidal illumination. In first experiment, handcrafted texture features were extracted from direct component (DC, corresponding to conventional uniform illumination) and amplitude component (AC, unique to the use of sinusoidal illumination) images retrieved from raw SIRI pattern images build linear discriminant analysis (LDA) models for classifying normal and defective samples. A further validation experiment was performed using deep learning as a feature extractor followed by LDA. The third experiment was on microbial spoilage assessment of broiler meat, deep learning models were used to extract features from DC and AC images builds on classifiers. Overall, this research has demonstrated consistent improvements of AC over DC images in assessing WS and spoilage of broiler meat and that SIRI is a promising tool for poultry meat quality detection.
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Quantitation Strategies in Optically Sectioning Fluorescence Microscopy / Quantifizierungsstrategien in der optisch schnittbildenden FluoreszenzmikroskopieWeigel, Arwed 15 January 2009 (has links)
No description available.
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Proteins bind Neutrophil extracellular traps in specific patternsWinkler, Jonay Moritz Julius 24 June 2024 (has links)
Neutrophile sind die häufigsten weißen Blutkörperchen im menschlichen Blut. Sie bilden die
erste Verteidigungslinie und töten eindringende Krankheitserreger ab. Neutrophile
extrazelluläre Fallen (NETs) sind netzartige Strukturen, die aus dekondensiertem Chromatin
bestehen und mit zytotoxischen Proteinen dekoriert sind. NETs können Mikroben in vitro
und in vivo einfangen und abtöten, sind aber auch für verschiedene Krankheiten
verantwortlich. Frühere Studien haben eine spezifische Gruppe von 20-50
Neutrophilenproteinen identifiziert, die an NETs gebunden sind und von denen einige eine
mikrobizide Wirkung haben. Wie diese Proteine an die NETs binden, wie sie interagieren
und wie die Bindung ihre antimikrobielle Aktivität beeinflusst, ist noch nicht bekannt.
In dieser Dissertation habe ich die Verteilung von acht neutrophilen Proteinen und
Nukleosomen auf NETs mit Hilfe der Superauflösungsmikroskopie untersucht. Es wurden
drei unabhängige Techniken mit Auflösungen von mehr als 90 nm verwendet. Die
Nukleosomen bildeten auf den NETs periodische Cluster mit deutlich größeren Abständen
im Vergleich zum kondensierten Chromatin. Drei NET-Proteine waren ebenfalls in
periodischen Clustern auf den NETs lokalisiert und zwei von ihnen waren stark mit
Nukleosomen kolokalisiert. Alle anderen analysierten Proteine zeigten keine Muster der
Bindung an NETs. Zusammengenommen zeigen diese Ergebnisse, dass die Bindung von
Proteinen an NETs zumindest teilweise spezifisch ist und teilweise durch Wechselwirkungen
mit Nukleosomen vermittelt wird.
Die erfolgreiche Einführung der superauflösenden Mikroskopie für schwierige NET-Proben
in Kombination mit einem vorgeschlagenen rekonstituierten NET-System eröffnet neue
Möglichkeiten für das Verständnis der molekularen Mechanismen der NET-Bildung und der
Protein-Protein-Interaktion bei der NET-vermittelten Abtötung. / Neutrophils are the most abundant human white blood cell in circulation. They are the first
line of defense and kill invading pathogens. Neutrophil Extracellular Traps (NETs) are weblike
structures composed of decondensed chromatin decorated with cytotoxic proteins. NETs
can trap and kill microbes in vitro and in vivo, but also mediate several diseases. Previous
studies identified a specific set of 20-50 neutrophil proteins bound to NETs, several with
microbicidal activity. It remains unknown how these proteins bind to NETs, how they interact
and how binding influences their anti-microbial activity.
In this dissertation, I studied the distribution of eight neutrophil proteins and nucleosomes
on NETs using super-resolution microscopy. Three independent techniques with resolutions
larger than 90nm were used. Nucleosomes formed periodic clusters on NETs, with
significantly larger spacing compared to condensed chromatin. Three NET proteins also
localized in periodic clusters on NETs and two of them strongly co-localized with
nucleosomes. All other proteins analyzed showed no patterns binding to NETs. Taken
together, these findings demonstrate that, at least some, protein binding to NETs is specific
and in part mediated by interactions with nucleosomes.
The successful introduction of super-resolution microscopy to the challenging NET samples
in combination with a proposed reconstituted NET system opens new possibilities to
understand the molecular mechanisms behind NET formation and protein-protein
interaction in NET mediated killing.
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