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Implication des biofilms dans la rhinosinusite chronique et l’évaluation des traitements avec un modèle in vitroBendouah, Zohra 08 1900 (has links)
Introduction : La chronicité de la rhinosinusite, sa résistance aux antibiotiques, et ses exacerbations aiguës laissent croire que les biofilms sont impliqués dans la rhinosinusite chronique. Objectifs : Nous avons évalué la capacité des bactéries Pseudomonas aeruginosa, staphylocoques à coagulase négative et Staphylococcus aureus à former des biofilms par un essai in vitro, et si cette capacité de formation a un lien avec l’évolution de la maladie. Nous avons évalué in vitro l’effet de la moxifloxacine, un antibiotique utilisé dans le traitement de la rhinosinusite chronique sur des biofilms matures de Staphylococcus aureus. Méthodes : Trent et une souches bactériennes ont été isolées de 19 patients atteints de rhinosinusite chronique et qui ont subit au moins une chirurgie endoscopique des sinus. L’évolution de la maladie a été notée comme "bonne" ou "mauvaise" selon l’évaluation du clinicien. La production de biofilm a été évaluée grâce à la coloration au crystal violet. Nous avons évalué la viabilité du biofilm après traitement avec la moxifloxacine. Ces résultats ont été confirmés en microscopie confocale à balayage laser et par la coloration au LIVE/DEAD BacLight. Résultat et Conclusion : Vingt deux des 31 souches ont produit un biofilm. La production d’un biofilm plus importante chez Pseudomonas aeruginosa et Staphylococcus aureus était associée à une mauvaise évolution. Ceci suggère un rôle du biofilm dans la pathogenèse de la rhinosinusite chronique. Le traitement avec la moxifloxacine, à une concentration de 1000X la concentration minimale inhibitrice réduit le nombre des bactéries viables de 2 à 2.5 log. Ces concentrations (100 µg/ml - 200 µg/ml) sont faciles à atteindre dans des solutions topiques. Les résultats de notre étude suggèrent que l’utilisation de concentrations supérieure à la concentration minimale inhibitrice sous forme topique peut ouvrir des voies de recherche sur de nouveaux traitements qui peuvent être bénéfiques pour les patients atteints de forme sévère de rhinosinusite chronique surtout après une chirurgie endoscopique des sinus. / Introduction: The role of biofilms in chronic diseases is increasingly recognized. Chronic rhinosinusitis, with its chronic indolent course, resistance to antibiotics, and acute exacerbations, has an evolution that parallels that of other biofilm-related diseases. Objectives: 1-To develop an in vitro method to assess the biofilm formation capacity. 2- To determine whether biofilm-forming capacity of bacteria demonstrated in chronic rhinosinusitis has an impact on persistence of the disease following endoscopic sinus surgery. 3- To determine the in vitro activity of moxifloxacin against Staphyylococcus aureus in biofilm form. Method: Thirty-one bacterial strains recovered from 19 patients with chronic rhinosinusitis at least one year post-endoscopic sinus surgery. Evolution of disease was assessed by questionnaire and endoscopy as favorable or unfavorable. The bacteria were cultured on a 96-well culture plaque and a semi-quantitative method using crystal violet to quantify biofilm production was used. Confirmation of the effect of the antimicrobial agents on viability was performed with confocal laser microscopy, using a LIVE/DEAD BacLight staining. Results: Twenty-two of 31 samples produced a biofilm thicker or equal to the positive control. Biofilm formation was associated with a poor evolution for Pseudomonas aeruginosa and Staphylococcus aureus, but not for coagulase-negative staphylococci. Biofilm treated with moxifloxacin at 1000X (0.1mg/ml – 0.2 mg/ml) gave a 2 to 2.5 log reduction in number of viable bacteria. Conclusion: We have shown that Crystal violet method is able to detect biofilm formation. There is a correlation between in vitro biofilm production by Pseudomonas aeruginosa and Staphylococcus aureus and unfavorable evolution after endoscopic sinus surgery, suggesting a role for biofilm in chronic rhinosinusitis. Increased concentrations of moxifloxacin, easily attainable in topical solutions have a potential role in the management of biofilm infections.
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Life on the Edge: Structural Analysis of Forest Edges to Aid Urban ManagementBenjamin Zachary McCallister (11205411) 30 July 2021 (has links)
<div>The accelerating expansion of agricultural and urban areas fragments and degrades forests</div><div>and their capacity to provide essential ecosystem services while increasing physiological stress</div><div>and mortality rates of trees growing near forest edges. Previous studies have documented that</div><div>edges are hotter and drier than forest interiors and trees nearer the edge grow slower. However,</div><div>the physical structure of a forest’s canopy may serve to mitigate to these effects. This study</div><div>quantifies forest fragmentation across the Central Hardwoods Region (CHR; containing Missouri,</div><div>Illinois, and Indiana) and characterizes structural differences between the canopies of forest edges</div><div>and forest interiors. Importantly, we distinguish between edges that neighbor developed land and</div><div>agricultural lands since these landcover types may impose distinct effects on forest structure. We</div><div>characterized forest canopy structure in a subset of the CHR region using the 2016-2020 Indiana</div><div>3DEP Lidar Program data. Our findings indicate edge forest (forests within 30m of an edge) makes</div><div>up 29.8% of the total forest in our study extent, with urban and agricultural edges accounting for</div><div>17.8% and 72.8% of the edge edges in the region, respectively. Analysis of 15 separate structural</div><div>metrics derived from aerial laser scanning (ALS) showed no significant structural differences</div><div>between developed and agricultural edge canopies but did find differences between structure of</div><div>canopies in forest cores and those in forest edges of any kind. As developed and agricultural lands</div><div>increase so too will forest fragmentation and the creation of new forest edges. If there are no</div><div>significant differences between forest edge types, then we could begin to treat edges without</div><div>distinction. This could lead to simplified management practices for foresters and urban foresters</div><div>alike to protect and preserve forest fragments.</div>
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Crime scenes in Virtual Reality : A user centered study / Brottsplatser i Virtuell Verklighet : En användarcentrerad studieDath, Catrin January 2017 (has links)
A crime scene is a vital part of an investigation. There are however, depending on the situation and crime, issues connected to physically being at the scene; risk of contamination, destruction of evidence or other issues can hinder the criminal investigators to stay, visit or revisit the scene. It is therefore important to visually capture the crime scene and any possible evidence in order to aid the investigation. This thesis aims to, with an initial research question, map out the main visual documentation needs, wishes and challenges that criminal investigators face during an investigation. In addition, with a second research question, it aims to address these in a Virtual Reality (VR) design and, with a third research question, explore however other professions in the investigation process could benefit from it. This was conducted through a literature review, interviews, workshops and iterations with the approach of the Double Diamond Model of Design. The results from the interviews were thematically analyzed and ultimately summarized into five key themes. These, together with various design criteria and principals, acted as design guidelines when creating a high fidelity VR design. The first two research questions were presented through the key themes and the VR design. The results of the third research question indicated that, besides criminal investigators, both prosecutors and criminal scene investigators may benefit from a VR design, although in different ways. A VR design can, in conclusion, address the needs, wishes and challenges of criminal investigators by being developed as a compiled visualization and collaboration tool. / En brottsplats är en vital del av en brottsundersökning. Det finns emellertid, beroende på situation och brott, problem som är kopplade till att fysiskt befinna sig på brottsplatsen. Risk för kontamination, förstörelse av bevis eller andra problem kan hindra brottsutredarna att stanna, besöka eller återvända till brottsplatsen. Det är därför viktigt att visuellt dokumentara brottsplatsen och eventuella bevis för att bistå utredningen. Detta masterarbete ämnar att, med en första forskningsfråga, kartlägga de viktigaste behoven, önskemålen och utmaningarna gällande visuell dokumentation, som brottsutredare möter under en utredning. Vidare ämnar projektet att, med en andra forskningsfråga, möta dessa i en Virtuell Verklighet (VR) -design och, med en tredje forskningsfråga, undersöka hur andra yrkesgrupper i en utredningsprocess skulle kunna dra nytta av den. Detta genomfördes genom en litteraturstudie, intervjuer, workshops och iterationer grundat i tillvägagångssättet Double Diamond Model of Design. Resultaten från intervjuerna analyserades tematiskt och sammanfattades i fem huvudteman. Dessa teman, tillsammans med olika designkriterier och principer, agerade designriktlinjer vid skapandet av en high-fidelity VR-design. De två första frågorna presenterades genom nyckeltemana och VR-designen. Resultaten gällande den tredje forskningsfrågan visar att, utöver brottsutredare, både åklagare och kriminaltekniker kan dra nytta av en VR-design, även om på olika vis. Sammanfattningsvis kan en VRdesign möta utredarnas behov, önskemål och utmaningar gällande visuell dokumentation genom att utvecklas som ett kompilerat visualiserings- och samarbetsverktyg.
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Rauheitsuntersuchungen an Glaskanten mittels konfokalem Laserscanning-MikroskopBukieda, Paulina, Weller, Bernhard 22 February 2024 (has links)
Untersuchungen zur Kantenfestigkeit von Gläsern zeigen, dass diese in Abhängigkeit des Herstellers und der Kantenbearbeitungsart nach DIN 1249-11 stark variiert. Insbesondere der Bearbeitungsprozess des Schleifens weist eine Vielzahl von Parametern auf, welche die resultierende Oberflächenbeschaffenheit der Glaskante beeinflussen, allerdings noch unzureichend untersucht sind. Eine objektive Erfassung der Oberflächenbeschaffenheit über Kennwerte der Rauheit könnte helfen, Prozessparameter bewertbar zu machen und eine Korrelation zwischen dem Bearbeitungsprozess und der Kantenfestigkeit zu schaffen. Im Rahmen einer ersten Vorstudie wurden Rauheitskennwerte geschliffener und polierter Kantenoberflächen von drei Herstellern mittels konfokalem Laserscanning-Mikroskop ermittelt und hinsichtlich ihrer Eignung zur Bewertung der Bearbeitungsprozesse geprüft. / Roughness examination of processed glass edges under a confocal laser scanning microscope. Findings on the edge strength show that, it varies depending on the manufacturer and the type of edge finishing. In particular the grinding process has a large number of parameters that influence the surface quality of the glass edge, which have not yet been fully investigated. The determination of objective roughness parameters could help to evaluate the grinding processes and further correlate the surface quality with the edge strength. Within the scope of a preliminary study, roughness parameters were calculated for ground and polished glass edges of three manufacturers using a confocal laser scanning microscope. Finally the method was tested regarding to its suitability for a determination of characteristic roughness parameters that could be used to evaluate the grinding processes.
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An Experimental Approach for the Determination of the Mechanical Properties of Base-Excited Polymeric Specimens at Higher Frequency ModesKucher, Michael, Dannemann, Martin, Böhm, Robert, Modler, Niels 27 October 2023 (has links)
Structures made of the thermoplastic polymer polyether ether ketone (PEEK) are widely
used in dynamically-loaded applications due to their high-temperature resistance and high mechanical
properties. To design these dynamic applications, in addition to the well-known stiffness and
strength properties the vibration-damping properties at the given frequencies are required. Depending
on the application, frequencies from a few hertz to the ultrasonic range are of interest here. To
characterize the frequency-dependent behavior, an experimental approach was chosen and applied
to a sample polymer PEEK. The test setup consists of a piezoelectrically driven base excitation of
the polymeric specimen and the non-contact measurement of the velocity as well as the surface
temperature. The beam’s bending vibrations were analyzed by means of the Timoshenko theory
to determine the polymer’s storage modulus. The mechanical loss factor was calculated using the
half-power bandwidth method. For PEEK and a considered frequency range of 1 kHz to 16 kHz, a
storage modulus between 3.9 GPa and 4.2 GPa and a loss factor between 9 103 and 17 103
were determined. For the used experimental parameters, the resulting mechanical properties were
not essentially influenced by the amplitude of excitation, the duration of excitation, or thermal
degrad.ation due to self-heating, but rather slightly by the clamping force within the fixation area.
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Bone material characteristics influenced by osteocytesKerschnitzki, Michael 01 March 2012 (has links)
In dieser Doktorarbeit wird die Hypothese geprüft, ob Osteozyten einen direkten Einfluss auf die Knocheneigenschaften in ihrer unmittelbaren Umgebung haben. Der zentrale Experimentieransatz ist dabei die Korrelation der Organisation des Osteozytennetzwerks mit den Mineraleigenschaften des Knochens auf der Submikrometerebene. Es wird gezeigt, dass bereits die anfängliche Ausrichtung der Osteoblasten entscheidend für die Synthese von hoch ausgerichtetem Knochenmaterial ist. Die dabei entstehenden Osteozytennetzwerke sind so organisiert, dass die Osteozyten und ihre Zellfortsätze jeweils einen möglichst kleinen Abstand zum Knochenmineral haben. Deshalb wird vermutet, dass genau diese Netzwerkorganisation mitentscheidend ist, wie gut die Zellen das Mineral in ih-rer Umgebung beeinflussen können. Messungen der Knochenmineraleigenschaften auf Submikrometerebene mit Röntgenkleinwinkelstreuung bestätigen diese Vermutung. Dabei wird deutlich, dass Knochenmaterial in der Nähe der Osteozyten durch andere Mineraleigenschaften geprägt ist. Um zu klären, wie Osteozyten Mineral in ihrer direkten Umgebung verändern können, werden Mechanismen der passiven Mineralherauslösung aus der mineralisierten Oberfläche des Osteozytennetzwerks untersucht. Es wird gezeigt, dass kalziumarme ionische Lösungen unter physiologischen Bedingungen große Mengen von Kalzium-Ionen aus dem Knochen lösen und diese dann durch die Osteozytennetzwerkstrukturen diffundieren können. Zum Abschluss wurde medullärer Knochen von Hühnern als ein Modellsystem für rasanten Knochenumbau untersucht. Dieser spezielle Knochentyp dient den Hennen als labiles Kalziumreservoir und ermöglicht dadurch die tägliche Eierschalenproduktion. Experimente am medullären Knochen-material zeigen insbesondere die Bedeutung von weniger stabilen Mineralstrukturen die benötigt werden um den Knochen an den schnellen, sich wiederholenden Knochenauf- sowie Abbau optimal anzupassen. / This thesis aims to test the hypothesis whether osteocytes have a direct influence on bone material properties in their vicinity. In this regard, the concomitant ana-lysis of osteocyte network organization and bone ultrastructural properties on the submicron level is the central approach to answer this question. In this work, it is shown that already initial cell-cell alignment during the process of bone formation is crucial for the synthesis of highly organized bone. Furthermore it is proposed that the occurrence of highly ordered osteocyte networks visualized with confocal laser scanning microscopy (CLSM) has a strong impact on the ability of osteocytes to directly influence bone material properties. These highly organized networks are another consequence of initial cell-cell alignment and are found to be arranged such as to feature short mineral cell distances. Examination of sub-micron mineral properties with scanning small angle x-ray scattering (sSAXS) shows that bone material in the direct vicinity of osteocytes and their cell proc-esses shows different mineral properties compared to bone further away in the depth of the tissue. Moreover, mechanisms of passive mineral extraction from the mineralized surface of the osteocyte network, due to the treatment with calcium poor ionic solutions, are investigated. It is shown that this chemical process occurring under physiological conditions leads not only to the dissolution of considerable amounts of calcium, but also to efficient diffusion of these ions through the osteocyte network structures. Finally, medullary bone which is intended as a labile calcium source for daily egg shell formation in hens is used as a model system for rapid bone turnover rates. This bone type in particular indicates the importance of uniquely adapted, less stable mineral structures to fit the requirements for rapid bone resorption as well as reformation.
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Regenerationspotenzial CD133+-hämatopoetischer Progenitorzellen der humanen Nabelschnur beim Nierendefekt im Mausmodell / Regenerative potential of human umbilical cord blood derived CD133 positive hematopoietic progenitor cells after kidney injury in a mouse modelHoffschulte, Birgit 19 August 2009 (has links)
No description available.
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Optical Analysis of [Ca<sup>2+</sup>]i and Mitochondrial Signaling Pathways: Implications for the Selective Vulnerability of Motoneurons in Amyotrophic Lateral Sclerosis (ALS) / Optische Analysen von [Ca<sup>2+</sup>]i und mitochondrialen Signalwegen: Untersuchungen zur selektiven Verwundbarkeit von Motoneuronen in der amyotrophen Lateralsklerose (ALS)Jaiswal, Manoj Kumar 23 January 2008 (has links)
No description available.
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Development of an enzyme immobilization platform based on microencapsulation for paper-based biosensorsZhang, Yufen 11 1900 (has links)
Un papier bioactif est obtenu par la modification d’un papier en y immobilisant une ou plusieurs biomolécules. La recherche et le développement de papiers bioactifs est en plein essor car le papier est un substrat peu dispendieux qui est déjà d’usage très répandu à travers le monde. Bien que les papiers bioactifs n’aient pas connus de succès commercial depuis la mise en marche de bandelettes mesurant le taux de glucose dans les années cinquante, de nombreux groupes de recherche travaillent à immobiliser des biomolécules sur le papier pour obtenir un papier bioactif qui est abordable et possède une bonne durée de vie. Contrairement à la glucose oxidase, l’enzyme utilisée sur ces bandelettes, la majorité des biomolécules sont très fragiles et perdent leur activité très rapidement lorsqu’immobilisées sur des papiers. Le développement de nouveaux papiers bioactifs pouvant détecter des substances d’intérêt ou même désactiver des pathogènes dépend donc de découverte de nouvelles techniques d’immobilisation des biomolécules permettant de maintenir leur activité tout en étant applicable dans la chaîne de production actuelle des papiers fins.
Le but de cette thèse est de développer une technique d’immobilisation efficace et versatile, permettant de protéger l’activité de biomolécules incorporées sur des papiers. La microencapsulation a été choisie comme technique d’immobilisation car elle permet d’enfermer de grandes quantités de biomolécules à l’intérieur d’une sphère poreuse permettant leur protection. Pour cette étude, le polymère poly(éthylènediimine) a été choisi afin de générer la paroi des microcapsules. Les enzymes laccase et glucose oxidase, dont les propriétés sont bien établies, seront utilisées comme biomolécules test. Dans un premier temps, deux procédures d’encapsulation ont été développées puis étudiées. La méthode par émulsion produit des microcapsules de plus petits diamètres que la méthode par encapsulation utilisant un encapsulateur, bien que cette dernière offre une meilleure efficacité d’encapsulation. Par la suite, l’effet de la procédure d’encapsulation sur l’activité enzymatique et la stabilité thermique des enzymes a été étudié à cause de l’importance du maintien de l’activité sur le développement d’une plateforme d’immobilisation. L’effet de la nature du polymère utilisé pour la fabrication des capsules sur la conformation de l’enzyme a été étudié pour la première fois.
Finalement, l’applicabilité des microcapsules de poly(éthylèneimine) dans la confection de papiers bioactifs a été démontré par le biais de trois prototypes. Un papier réagissant au glucose a été obtenu en immobilisant des microcapsules contenant l’enzyme glucose oxidase. Un papier sensible à l’enzyme neuraminidase pour la détection de la vaginose bactérienne avec une plus grande stabilité durant l’entreposage a été fait en encapsulant les réactifs colorimétriques dans des capsules de poly(éthylèneimine). L’utilisation de microcapsules pour l’immobilisation d’anticorps a également été étudiée.
Les avancées au niveau de la plateforme d’immobilisation de biomolécules par microencapsulation qui ont été réalisées lors de cette thèse permettront de mieux comprendre l’effet des réactifs impliqués dans la procédure de microencapsulation sur la stabilité, l’activité et la conformation des biomolécules. Les résultats obtenus démontrent que la plateforme d’immobilisation développée peut être appliquée pour la confection de nouveaux papiers bioactifs. / Biosensing paper attracts increasing attention due to its benefits of being simple, visible, portable and useful for detecting various contaminants, pathogens and toxins. While there has been no bioactive paper commercialized since glucose paper strips developed in the fifties, many research groups are working to immobilize biomolecules on paper to achieve a bioactive paper that is affordable and has good shelf life. The goal of this research is to develop some highly useful bioactive paper that could, for example, measure blood glucose, or immediately detect and simultaneously deactivate pathogens such as neuraminidase and E.coli. Previously, bioactive paper was produced either through physically absorbing biorecognition elements or printing bio-ink onto paper substrate. Our methodology for fabrication of bioactive paper strips is compatible with existing paper making process and includes three procedures: the fabrication of microcapsules, enzyme or antibody microencapsulation, immobilization of enzymes or antibody-entrapped microcapsules into paper pulp.
The first step, in fabricating of bioactive paper strips is to produce biocompatible and inexpensive microcapsules with suitable parameters. To do so, two types of microencapsulation methods were compared; the emulsion method and the vibration nozzle method accomplished with an encapsulator. The parameters for producing optimal microcapsules with both methods were studied. Factors that affect their diameter, wall thickness, shell pore size, encapsulation efficiency and membrane compositions were also discussed. By comparison, microcapsules prepared with poly(ethyleneimine) (PEI) by the emulsion method exhibit properties that were more suitable for enzyme encapsulation and paper making process, whereas the microcapsules prepared by the vibration nozzle method were too big to be immobilized within paper pulp, and had lower encapsulation efficiency, enzymatic activity and productivity. Thus the emulsion method was chosen for subsequent experiments such as enzyme and antibody microencapsulation and bacterial vaginosis (BV) paper preparation. Microcapsules made by the emulsion method were semi-permeable in that the diffusion of substrate and product molecules were allowed freely across the membranes but the encapsulated enzymes would be retained inside.
Glucose oxidase from Aspergillus niger (GOx) and laccase from Trametes versicolor (TvL) microcapsules showed high encapsulation efficiency, but the encapsulation process caused a severe decrease in the specific activities of both enzymes. Results from circular dichroism (CD) studies, fluorescence properties, enzymatic activities of free enzymes and Michaelis-Menten behavior demonstrated that the Vmax decrease for GOx was due to the restriction of diffusion across microcapsule membranes with pore size less than 5 nm. The microencapsulation process improved the thermal stability of GOx but decreased that of laccase.
Bioactive papers were fabricated either by incorporating microcapsules containing different enzymes or empty microcapsules soaked in substrate and enhancer solution into the paper pulp during the sheet making process. Both the GOx and the BV paper strips underwent a color change in the presence of glucose and potassium iodide, and sialidase from Clostridium perfringens respectively. Some preliminary studies on antibody sensitized microcapsules, in which antibody was either encapsulated within the PEI microcapsules or conjugated to its membranes, were also performed.
Our objective was to establish an enzyme immobilization platform based on microencapsulation techniques for paper based biosensors. Even though our current studies only focused on the microencapsulation of two enzymes, TvL and GOx, as well as the bioactive paper preparation, a similar approach can be applied to other enzymes. We believe that this immobilization method can potentially be employed for bioactive paper preparation on an industrial scale.
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Estimation cohérente de l'indice de surface foliaire en utilisant des données terrestres et aéroportées / Consistent forest leaf area index retrieval using ground and airborne dataHu, Ronghai 27 August 2018 (has links)
L’indice de surface foliaire (Leaf Area Index, LAI), défini comme la moitié de la surface foliaire par unité de surface de sol, est un paramètre clé du cycle écologique de la Terre, et sa précision d'acquisition a toujours la nécessité et la possibilité d'amélioration. La technologie du scanner laser actif offre une possibilité d'obtention cohérente du LAI à plusieurs échelles, car le scanner laser terrestre et le scanner laser aéroporté fonctionnent sur le même mécanisme physique. Cependant, les informations tridimensionnelles du scanner laser ne sont pas complètement explorées dans les méthodes actuelles et les théories traditionnelles ont besoin d'adaptation. Dans cette thèse, le modèle de distribution de longueur de trajet est introduit pour corriger l'effet d’agrégation, et il est appliqué aux données du scanner laser terrestre et du scanner laser aéroporté. La méthode d'obtention de la distribution de longueur de trajet de différentes plates-formes est étudiée et le modèle de récupération cohérent est établi. Cette méthode permet d’améliorer la mesure du LAI des arbres individuels dans les zones urbaines et la cartographie LAI dans les forêts naturelles, et ses résultats sont cohérents à différentes échelles. Le modèle devrait faciliter la détermination cohérente de l'indice de surface foliaire des forêts à l'aide de données au sol et aéroportées. / Leaf Area Index (LAI), defined as one half of the total leaf area per unit ground surface area, is a key parameter of vegetation structure for modeling Earth's ecological cycle and its acquisition accuracy always has the need and opportunity for improvement. Active laser scanning provides an opportunity for consistent LAI retrieval at multiple scales because terrestrial laser scanning (TLS) and airborne laser scanning (ALS) have the similar physical mechanism. However, the three-dimensional information of laser scanning is not fully explored in current methods and the traditional theories require adaptation. In this thesis, the path length distribution model is proposed to model the clumping effect, and it is applied to the TLS and ALS data. The method of obtaining the path length distribution of different platforms is studied, and the consistent retrieval model is established. This method is found to improve the individual tree measurement in urban areas and LAI mapping in natural forest, and its results at consistent at different scales. The model is expected to facilitate the consistent retrieval of the forest leaf area index using ground and airborne data.
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