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Sammanhanget och naturen : En intervjustudie med seniorer i en intervention under covid-19-pandeminEriksson, Karolina January 2021 (has links)
Seniorer är en utsatt grupp under covid-19-pandemin då de riskerar att drabbas av allvarlig sjukdom eller död till följd av covid-19. Samtidigt innebär de restriktioner som har införts för att skydda mot covid-19 stora förändringar i människors vardag och riskerar att påverka den psykiska likväl som den fysiska hälsan negativt. Naturen påverkar däremot hälsan positivt på en rad olika sätt och människan tenderar att återhämta sig mer gynnsamt i kontakt med naturen. Naturen kan även utgöra en resurs för att hantera stress under en kris på ett bättre sätt. Den salutogena teorin känsla av sammanhang (KASAM) med delarna begriplighet, hanterbarhet och meningsfullhet, Attention Restoration Theory samt Supportive Environment Theory har använts som teoretiska ramverk i studien. Träffpunkten flyttar ut var en intervention med syfte att öka förekomsten av enkla friluftsaktiviteter i närnatur bland seniorer med mål att främja hälsan. I studien har tolv seniorer som deltog i träffpunkter förlagda utomhus deltagit i en semistrukturerad intervju. Materialet har analyserats med en kvalitativ innehållsanalys med induktiv ansats. Resultatet visar att seniorerna påverkades positivt socialt, fysiskt och psykiskt på ett holistiskt sätt genom interventionen, att naturen hade en gynnsam effekt för välmående och slutligen att seniorerna hade olika förhållningssätt i pandemin. Förhållningssätten utgjordes av inre och yttre strategier där samhörighet och sysselsättning framkom som yttre strategier där träffpunkten hade en betydande roll. Implikationen är att interventioner som använder naturen som arena kan utgöra en preventiv och hälsofrämjande åtgärd för seniorer som är betydelsefull för att främja folkhälsan i en kris såsom covid-19-pandemin. / Seniors are a vulnerable group during the COVID-19 pandemic as they are at risk of suffering from serious illness or death from COVID-19. At the same time, the restrictions that have been introduced to protect against COVID-19 have implied major changes in people's everyday lives and risk affecting the mental as well as the physical health negatively. Nature has a positive effect on health in various ways and humans tend to recover more favorably in contact with nature. Nature can also be a resource for dealing with stress during a crisis. The salutogenic theory Sense of Coherence (SOC) including the aspects of comprehensibility, manageability, and meaningfulness, has been used as a theoretical framework in the study. Twelve semi-structured interviews have been carried out with seniors who participated in meeting places outdoors. The material has been analyzed with a qualitative content analysis with an inductive approach. The results show that the seniors were influenced positively socially, physically, and mentally in a holistic way through the intervention. Furthermore, it emerged that nature has a beneficial effect for well-being and that different attitudes emerged in the pandemic among the seniors. The attitudes consisted of internal and external strategies where cohesion and carrying out activities emerged as external strategies where the meeting point had a significant role. The implication is that interventions using nature as an arena can constitute a preventive and health-promoting measure for seniors that is important for improving public health in a crisis such as COVID-19 pandemic.
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Omnidirectional Phase Matching In Zero-Index MediaGagnon, Justin 22 April 2021 (has links)
Since its inception, the field of nonlinear optics has only increased in importance as a result of a growing number of applications. The efficiency of all parametric nonlinear optical processes is limited by challenges associated with phase-matching requirements. To address this constraint, a variety of approaches, such as quasi-phase-matching, birefringent phase matching, and higher-order-mode phase matching have historically been used to phase-match interactions. However, the methods demonstrated to date suffer from the inconvenience of only being phase-matched for one specific arrangement of beams, typically co-propagating along the same axis. This stringency of the phase-matching requirement results in cumbersome optical configurations and large footprints for integrated devices. In this thesis, we show that phase-matching requirements in parametric nonlinear optical processes may be satisfied for all orientations of input and output beams when using zero-index media: a condition of omnidirectional phase matching. To validate this theory, we perform experimental demonstrations of phase matching for five separate FWM beam configurations to confirm this phenomenon. Our measurements constitute the first experimental observation of the simultaneous generation of a forward- and backward-propagating signal with respect to the pump beams in a medium longer than a free-space optical wavelength, allowing us to determine the coherence length of our four-wave-mixing process. Our demonstration includes nonlinear signal generation from spectrally distinct counter-propagating pump and probe beams, as well as the excitation of a parametric process with the probe beam's wave vector orthogonal to the wave vector of the pump beam. By sampling all of these beam configurations, our results explicitly demonstrate that the unique properties of zero-index media relax traditional phase-matching constraints, and provide strong experimental evidence for the existence of omnidirectional phase matching in zero-index media. This property can be exploited to facilitate nonlinear interactions and miniaturize nonlinear devices, and adds to the established exceptional properties of low-index materials.
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Proměny genderových archetypů ve filmu Hořký měsíc / Bitter Moon - The transformation of gender identity ( directed by Roman Polanski)Astapencov, Neli January 2013 (has links)
The thesis deals with gender analysis in films studying metamorphoses of archetypes in film Bitter Moon directed by Roman Polanski. The methodical and theoretical sections of the thesis analyse the influence of archetype changes of film characters in gender roles. The thesis identifies and analyses mainly woman film characters appearing in some classical feminist texts, feminist film theoretical and critical articles, in some psychoanalytical works, in dramatheraphy and film science. The sources mentioned above became primary resource materials for our archetypal research. The analysis of each of the film character is focused on the most distinctive archetype with respect to its metamorphosy. Apart from the archetype research the thesis is marginaly concerned with problems linked to the female ideal and her sexuality usually portrayed in an unalterable way, and archetypal patterns are in such a way transmitted to audiences through femininity and masculinity in the context of gender roles. Keywords: archetype, Roman Polanski, Laura Mulvey, Annis Pratt, cinematic archetypal coherence, feminist film criticism, film narrative analysis, archetypal masculinity, archetypal femininity.
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Quantitative Analyse retinaler Veränderungen bei nichtglaukomatösen Optikusatrophien mit Hilfe der Optischen KohärenztomographieKühn, Elisabeth 28 April 2011 (has links)
Nichtglaukomatöse Optikusatrophien führen nicht nur zu einer Verminderung der Dicke der retinalen Nervenfaserschicht (RNFL) sondern auch zu einer Reduktion des Makulavolumens. In dieser Arbeit wurde mit Hilfe der optischen Kohärenztomographie (OCT) untersucht, welche Schichten der Makula von Dickenveränderungen als Folge einer Optikusatrophie betroffen sind. Es wurden 27 Patienten mit nichtglaukomatösen Optikusatrophien unterschiedlicher Ätiologie (postneuritische, hereditäre und traumatische Atrophien) und 21 augengesunde Kontrollpersonen untersucht. OCT-Scans der RNFL und der Makula wurden mit Hilfe des Stratus OCT 3000 (Carl Zeiss Meditec) durchgeführt. Die axialen Reflektivitätsprofile der radialen Scans wurden aus den exportierten JPEG-Bildern an zwölf Punkten in je 1,5mm Entfernung von der Foveola vermessen und gemittelt. Das charakteristische Reflektivitätsprofil mit fünf Intensitätsmaxima und vier Intensitätsminima wurde der Lokalisation der einzelnen Makulaschichten zugeordnet. Die von nichtglaukomatöser Optikusatrophie betroffenen Augen wiesen im Vergleich zu den Augen der augengesunden Normalpersonen signifikant (p<0,05) reduzierte RNFL-Dicken (um 35,5% reduziert) und Makulavolumen-Werte (um 11,8% reduziert) auf. Bei allen untersuchten Formen der Optikusatrophie waren nicht nur die makuläre Nervenfaserschicht (MNFL) sondern alle inneren Schichten der Makula verdünnt. Die mittlere Reduktion betrug 21,2% für die MNFL, 39,7% für die Ganglienzellschicht, 33,2% für die innere plexiforme Schicht und 9,4% für die innere Körnerzellschicht im Vergleich zu den Werten der Normalpersonen. Veränderungen der äußeren Netzhautschichten traten nur bei den posttraumatischen Atrophien auf.
Eine Beurteilung der Dicke aller einzelnen Netzhautschichten aus OCT-Scans ist mit Hilfe geräteintegrierter Software bisher noch nicht möglich. Die quantitative Analyse der axialen Reflektivitätsprofile aus exportierten OCT-Bildern stellt eine geeignete Methode zur Beschreibung des Verlaufs und der Lokalisation von Makulaveränderungen bei Optikusatrophien verschiedener Genese dar.
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Measurement of surface topographies in the nm-range for power chip technologies by a modified low-coherence interferometerTaudt, Ch., Baselt, T., Nelsen, B., Aßmann, H., Greiner, A., Koch, E., Hartmann, P. 29 August 2019 (has links)
This work introduces a modified low-coherence interferometry approach for nanometer surface-profilometry. The key component of the interferometer is an element with known dispersion which defines the measurement range as well as the resolution. This dispersive element delivers a controlled phase variation which can be detected in the spectral domain and used to reconstruct height differences on a sample. In the chosen setup, both axial resolution and measurement range are tunable by the choice of the dispersive element.
The basic working principle was demonstrated by a laboratory setup equipped with a supercontinuum light source (Δλ = 400 ̶ 1700 nm). Initial experiments were carried out to characterize steps of 101 nm on a silicon height standard. The results showed that the system delivers an accuracy of about 11.8 nm. These measurements also served as a calibration for the second set of measurements. The second experiment consisted of the measurement of the bevel of a silicon wafer. The modified low-coherence interferometer could be utilized to reproduce the slope on the edge within the previously estimated accuracy. The main advantage of the proposed measurement approach is the possibility to collect data without the need for mechanically moving parts.
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Two-dimensional low-coherence interferometry for the characterization of nanometer wafer topographiesTaudt, Ch., Baselt, T., Nelsen, B., Aßmann, H., Greiner, A., Koch, E., Hartmann, P. 30 August 2019 (has links)
Within this work a scan-free, low-coherence interferometry approach for surface profilometry with nm-precision is presented. The basic setup consist of a Michelson-type interferometer which is powered by a supercontinuum light-source (Δλ = 400 - 1700 nm). The introduction of an element with known dispersion delivers a controlled phase variation which can be detected in the spectral domain and used to reconstruct height differences on a sample. In order to enable scan-free measurements, the interference signal is spectrally decomposed with a grating and imaged onto a two-dimensional detector. One dimension of this detector records spectral, and therefore height information, while the other dimension stores the spatial position of the corresponding height values.
In experiments on a height standard, it could be shown that the setup is capable of recording multiple height steps of 101 nm over a range of 500 µm with an accuracy of about 11.5 nm. Further experiments on conductive paths of a micro-electro-mechanical systems (MEMS) pressure sensor demonstrated that the approach is also suitable to precisely characterize nanometer-sized structures on production-relevant components. The main advantage of the proposed measurement approach is the possibility to collect precise height information over a line on a surface without the need for scanning. This feature makes it interesting for a production-accompanying metrology.
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3D handheld endoscope for optical coherence tomography of the human oral mucosa in vivoWalther, Julia, Schnabel, Christian, Ebert, Nadja, Baumann, Michael, Koch, Edmund 06 September 2019 (has links)
The early non-invasive diagnosis of epithelial tissue alterations in daily clinical routine is still challenging. Since optical coherence tomography (OCT) shows the potential to differentiate between benign and malignant tissue of primal endothelium, OCT could be beneficial for the early diagnosis of malignancies in routine health checks. In this research, a new handheld endoscopic scanning unit was designed and connected to a spectral domain OCT system of our workgroup for the in vivo imaging of the human oral mucosa.
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Imaging of nanoparticle-labeled stem cells using magnetomotive optical coherence tomography, laser speckle reflectometry, and light microscopyCimalla, Peter, Werner, Theresa, Winkler, Kai, Mueller, Claudia, Wicht, Sebastian, Gaertner, Maria, Mehner, Mirko, Walther, Julia, Rellinghaus, Bernd, Wittig, Dierk, Karl, Mike O., Ader, Marius, Funk, Richard H. W., Koch, Edmund 09 September 2019 (has links)
Cell transplantation and stem cell therapy are promising approaches for regenerative medicine and are of interest to researchers and clinicians worldwide. However, currently, no imaging technique that allows three-dimensional in vivo inspection of therapeutically administered cells in host tissues is available. Therefore, we investigate magnetomotive optical coherence tomography (MM-OCT) of cells labeled with magnetic particles as a potential noninvasive cell tracking method. We develop magnetomotive imaging of mesenchymal stem cells for future cell therapy monitoring. Cells were labeled with fluorescent iron oxide nanoparticles, embedded in tissue-mimicking agar scaffolds, and imaged using a microscope setup with an integrated MM-OCT probe. Magnetic particle-induced motion in response to a pulsed magnetic field of 0.2 T was successfully detected by OCT speckle variance analysis, and cross-sectional and volumetric OCT scans with highlighted labeled cells were obtained. In parallel, fluorescence microscopy and laser speckle reflectometry were applied as two-dimensional reference modalities to image particle distribution and magnetically induced motion inside the sample, respectively. All three optical imaging modalities were in good agreement with each other. Thus, magnetomotive imaging using iron oxide nanoparticles as cellular contrast agents is a potential technique for enhanced visualization of selected cells in OCT.
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Toward a comprehensive interpretation of intravital microscopy images in studies of lung tissue dynamicsGaertner, Maria, Schirrmann, Kerstin, Schnabel, Christian, Meissner, Sven, Kertzscher, Ulrich, Kirsten, Lars, Koch, Edmund 09 September 2019 (has links)
Intravital microscopy (IVM) is a well-established imaging technique for real-time monitoring of microscale lung tissue dynamics. Although accepted as a gold standard in respiratory research, its characteristic image features are scarcely understood, especially when trying to determine the actual position of alveolar walls. To allow correct interpretation of these images with respect to the true geometry of the lung parenchyma, we analyzed IVM data of alveoli in a mouse model in comparison with simultaneously acquired optical coherence tomography images. Several IVM characteristics, such as double ring structures or disappearing alveoli in regions of liquid filling, could be identified and related to the position of alveoli relative to each other. Utilizing a ray tracing approach based on an idealized geometry of the mouse lung parenchyma, two major reflection processes could be attributed to the IVM image formation: partial reflection and total internal reflection between adjacent alveoli. Considering the origin of the reflexes, a model was developed to determine the true position of alveolar walls within IVM images. These results allow thorough understanding of IVM data and may serve as a basis for the correction of alveolar sizes for more accurate quantitative analysis within future studies of lung tissue dynamics.
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In vivo imaging of human oral hard and soft tissues by polarizationsensitive optical coherence tomographyWalther, Julia, Golde, Jonas, Kirsten, Lars, Tetschke, Florian, Hempel, Franz, Rosenauer, Tobias, Hannig, Christian, Koch, Edmund 09 September 2019 (has links)
Since optical coherence tomography (OCT) provides three-dimensional high-resolution images of biological tissue, the benefit of polarization contrast in the field of dentistry is highlighted in this study. Polarization-sensitive OCT (PS OCT) with phase-sensitive recording is used for imaging dental and mucosal tissues in the human oral cavity in vivo. An enhanced polarization contrast of oral structures is reached by analyzing the signals of the co- and crosspolarized channels of the swept source PS OCT system quantitatively with respect to reflectivity, retardation, optic axis orientation, and depolarization. The calculation of these polarization parameters enables a high tissue-specific contrast imaging for the detailed physical interpretation of human oral hard and soft tissues. For the proof-of-principle, imaging of composite restorations and mineralization defects at premolars as well as gingival, lingual, and labial oral mucosa was performed in vivo within the anterior oral cavity. The achieved contrast-enhanced results of the investigated human oral tissues by means of polarizationsensitive imaging are evaluated by the comparison with conventional intensity-based OCT.
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