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Artykuły w czasopismach na temat "Microscopie – Analyse informatique"
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Kucheriavyi, Y. P. "TRANSMISSION ELECTRON MICROSCOPY FOR THE DIRECT ANALYSIS OF FIBRIN CLOT STRUCTURE". Biotechnologia Acta 16, nr 2 (28.04.2023): 30–31. http://dx.doi.org/10.15407/biotech16.02.030.
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The aim of our study was to compare the structure of clots formed as a result of thrombin-induced fibrin polymerization in the presence or absence of monoclonal fibrin-specific antibodies fragments as factors that change the clot structure. We concentrated on the final stage of fibrin clot formation at maximal turbidity point for every sample. Methods. Fibrin polymerization was studied by transmission electron microscopy (TEM) of negatively contrasted samples on H-600 Transmission Electron Microscope (“Hitachi”,Japan); 1% water solution of uranyl acetate (“Merck”, Germany) was used as a negative contrast. For sample preparation, in sterile glass tubes were sequentially added 0.32 mg/mL human fibrinogen, 0.025 M CaCl2 in 0.05 M ammonium formiate buffer (pH 7.9), and a total sample volume was 0.22 mL. The polymerization of fibrin was initiated by the introduction of thrombin at a final concentration of 0.25 NIH/mL. After 180 s, aliquots were taken from the polymerization medium. Each aliquot was diluted to a final fibrinogen concentration of 0.07 mg/mL; 0.01 mL probes of fibrinogen solution were transferred to a carbon lattice, which was treated with a 1% uranyl acetate solution after 2 minutes. Investigations were per-formed using an H-600 electron microscope at 75 kV. Electron microscopic images were obtained at magnification of 20,000 -50,000. Results. Two monoclonal antibodies fragments were obtained towards the mixture of separated Aα-, Bβ- and γ-chains of fibrinogen. Antibodies fragments that were marked as III-1D and I-4A, had different epitopes within fragment Аα105-206 of D-region of fibrinogen. It was shown that addition of antibody fragment I-4A lead to formation of abnormal fibrils that were thinner than in the control sample and were organized in the dense network (Figure). Control sample exhibited the thick fibrils with well-structured classically organized network. The difference between control and I-4A samples demonstrated that antibody I-4A disrupted the structure of polymerized fibrin. In the same time the fibrils obtained in the presence of antibody fragment III-1D were closer to the control ones. Conclusions. TEM is an informative method for the study of the fibrin network formation. Its application allows to estimate the disruption in fi brin formation directly. In a combination with turbidity study and other functional tests TEM can provide important information about molecular mechanisms of clot formation.
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Rosen, Arlene Miller. "Ancient Town and City Sites: A View from the Microscope". American Antiquity 54, nr 3 (lipiec 1989): 564–78. http://dx.doi.org/10.2307/280783.
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Archaeological studies concerned with reconstructing activity areas, room functions, and site-formation processes can benefit greatly from analyses of the microartifacts found on and within occupation surfaces. These remains are often primary refuse directly related to activities, and can be used to identify such locations as food-preparation areas, flint-knapping stations, and storage facilities. In addition, certain microartifacts are informative about site-formation processes. For example, the grain-size distribution of charcoal may be indicative of primary vs. secondary refuse, high percentages of corroded and crushed bone from scavenger feces may indicate locations of secondary refuse, and many small sherds could point to heavily trampled areas. A case study from the Iron Age city site of Tel Miqne-Ekron in central Israel demonstrates the use of microarchaeology at a complex sedentary site.
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Demicheli, Romano, William Hrushesky, Michael Retsky i Elia Biganzoli. "Interpreting Breast Cancer Survival Data by the Hazard Function: Remarkable Findings from Event Dynamics". Medicina 56, nr 9 (12.09.2020): 468. http://dx.doi.org/10.3390/medicina56090468.
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The report addresses the role of the hazard function in the analysis of disease-free survival data in breast cancer. An investigation on local recurrences after mastectomy provided evidence that uninterrupted growth is inconsistent with clinical findings and that tumor dormancy could be assumed as working hypothesis to understand the clinical course of the disease. Additionally, it was deemed that the lag-time between primary tumor removal and tumor recurrence is dynamically dependent on the subclinical metastasis development within the host-tumor system and, therefore, may be informative about the biology of the disease. Accordingly, the hazard function, which estimates the event risk pattern through the time, was adopted to analyze survival data. The multipeak pattern of the hazard function suggested that the process metastasis development has discontinuous features. A new paradigm of breast cancer metastatic development was proposed, involving the notions of tumor homeostasis, tumor quiescence in specific metastatic microscopic phases and surgery-related acceleration of the metastatic process. All analyses by prognostic factors (e.g., by menopausal status) or treatment modalities (e.g., by adjuvant chemotherapy) or other parameters (e.g., site of metastasis), provided coherent data in agreement with the model. The hazard rate function allowed addressing several clinical questions including meaning of ipsilateral breast tumor recurrence (IBTR), oncologic effect of delayed breast reconstruction, surgery related metastasis acceleration, possible role of anti-inflammatory drugs and body mass index (BMI) to modulate the recurrence risk. We conclude that the hazard function is a powerful tool to investigate the post-surgical course of early breast cancer and other operable tumors and to make inferences on their biology.
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Iñiguez, Alena Mayo, Lorrayne Brito, Lucélia Guedes i Sergio Augusto de Miranda Chaves. "Helminth infection and human mobility in sambaquis: Paleoparasitological, paleogenetic, and microremains investigations in Jabuticabeira II, Brazil (2890 ± 55 to 1805 ± 65 BP)". Holocene 32, nr 3 (30.11.2021): 200–207. http://dx.doi.org/10.1177/09596836211060490.
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Sambaquis or shellmounds are archeological sites constructed by hunter-fisher-gatherers that inhabited the Brazilian coast about 10,000–2000 yrs BP. Jabuticabeira II (JABII: 2890 ± 55 to 1805 ± 65 BP) is one of dozens of contemporaneous sambaquis of the Santa Catarina state, South Brazil, and contains hundreds of neatly organized burials, indicating great population density. In order to gather information about the health, diet and way of life of people in JABII, a paleoparasitological, paleogenetic, and micro-human remains investigation was carried out. Pelvic region and environmental control samples from six individuals exhumed from JABII were submitted to microscopic and ancient DNA (aDNA) investigation. Paleoparasitological analyses based on light microscopy were negative. However, a variety of informative microremains were found. Diatoms, fish scales, and algae characterize the marine and estuarine environment. Ipomoea batatas and Zea mays starch grains suggested cultivated items as part of their diet in agreement with the literature. The finding of Podocarpus sp. pollen grain, characteristic of highlander vegetation, suggests human mobility of JABII individuals which were settlement in the coast. Paleogenetic analyses showed Ascaris sp. helminth infection based on nad1 gene fragment detected from an individual excavated at L3 FS7 burial (1826 ± 40 BP). This aDNA result places the antiquity of Ascaris sp. infection, and haplotypes that are circulating in humans and other animals nowadays, in Pre-Columbian South American times.
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Thuy, Ben, Larry Knox, Lea D. Numberger-Thuy, Nicholas S. Smith i Colin D. Sumrall. "Ancient deep ocean as a harbor of biotic innovation revealed by Carboniferous ophiuroid microfossils". Geology 51, nr 2 (3.01.2023): 157–61. http://dx.doi.org/10.1130/g050596.1.
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Abstract Fossil-informed molecular phylogenies have emerged as the most powerful tool for correlating biotic evolution and Earth history. The accuracy of these trees, however, depends on the completeness of fossil sampling. For most organismal clades, the available fossil record is insufficiently sampled. This is especially true for groups with a multi-element skeleton, such as echinoderms and vertebrates, where sampling efforts focus largely on rare finds of intact skeletons. For these groups, inconspicuous but informative skeletal fragments are commonly neglected. This sampling bias excludes the numerous paleoenvironments in which preservation of intact skeletons is extremely unlikely, in particular deep-water settings. We describe new finds of brittle-star, or ophiuroid, fossils retrieved from sieving residues of sediments deposited during the Atokan (Upper Carboniferous) on the deep shelf to upper slope of the Ardmore Basin in present-day southern Oklahoma, USA. Although preserved as disarticulated, microscopic ossicles, the pristine preservation of the skeletal microstructure allows for precise identification of the remains. Comparative anatomical and phylogenetic analyses confirm the presence of basal representatives of the extant ophiuroid orders Ophioscolecida and Amphilepidida. Our finds provide the first unambiguous fossil evidence that the early crown-group diversification of the Ophiuroidea was well under way long before the end-Permian mass extinction, and that a significant part of this diversification took place in deep-water settings, as previously predicted by molecular evidence.
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Boccacci, Giulia, Francesca Frasca, Chiara Bertolin i Anna Maria Siani. "Influencing Factors in Acoustic Emission Detection: A Literature Review Focusing on Grain Angle and High/Low Tree Ring Density of Scots Pine". Applied Sciences 12, nr 2 (14.01.2022): 859. http://dx.doi.org/10.3390/app12020859.
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Among non-destructive testing (NDT) techniques applied to structural health monitoring in existing timber structures, ranging from visual inspection to more sophisticated analysis, acoustic emission (AE) is currently seldomly used to detect mechanical stresses in wooden building assets. This paper presents the results from a systematic literature review on AE NDT applied to monitor micro and macro fracture events in softwood, specifically Scots pine. This survey particularly investigates its application with respect to the tree rings density and grain angle inspection, as influencing factors well correlated with physical and mechanical characteristics of wood. The literature review was performed in a three-step process defined by the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) flow diagram, leading to the selection of 31 documents from different abstract and citation databases (Scopus, Web of Science and Google Scholar). The outcomes have highlighted how laboratory experiments, including several types of tests (tensile, cutting, compressive, etc.), were conducted in most cases, while a very limited number of studies investigated on in situ monitoring. In addition, theoretical approaches were often explored in parallel with the experimental one. It emerges that—for tree ring density studies—a multi-technique approach, which may include microscopic observations, could be more informative. Indeed, although not widely investigated, high/low tree ring density and grain angle were found as influencing factors on the AE parameters detected by the sensors, during condition and structural health monitoring experiments.
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Burykina, S. I., S. P. Uzhevska i N. V. Pylyak. "METHOD OF ASSESSING THE NEMATOCIDAL EFFECTIVENESS OF A BIOPREPA-RATION BASED ON PREDATORY MICROMYCETE AGAINST THE POTATO STEM NEMATODE". Microbiology&Biotechnology, nr 3(59) (20.12.2023): 14–25. http://dx.doi.org/10.18524/2307-4663.2023.3(59).292392.
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Aim – Studing of methods for determining the effectiveness of Nematophagin BT against potato stem nematode in the laboratory. Materials and methods. For the experiment, potato tubers with signs of damage by the stem nematode Ditylenchus destructor Thorne, 1945 were selected. The method of treatment of cut potato tubers with the preparation was used. It was compared with the method of treatment of whole tubers in the laboratory. The effect of the microbiological nematicidal preparation (Nematofagin BT) developed by ITI Biotechnology of NAAS was determined. The effectiveness of the microbiological preparation of nematicidal action (Nematofagin BT), developed by ITI Biotechnology of NAAS, was determined. The active ingredient of the drug is a microscopic fungus-predator Arthrobotrys oligospora strain 12, the initial culture of which is deposited in the collection of microorganism cultures of the D.K. Zabolotny Institute of Microbiology and Virology of the National Academy of Sciences of Ukraine F100047. Results. The methods of laboratory evaluation of the nematicidal effect of the biological product against potato stem nematode are described. In laboratory conditions, to determine the effectiveness of the drug, it is more informative to use cut tubers that have been infected with stem nematode. This method requires much more time to set up, but the bioagent has bigger accessibility to the pest. The use of whole tubers is less labor-intensive, but there is a possibility of using uninfected material in the experiment. The expediency of using these methods in laboratory conditions for the selection of active strains and determination of their effectiveness is shown. Conclusion. The method of nematicidal treatment of cut tubers with established infection of stem nematode is more informative than the use of whole tubers. It is advisable to analyze for damage to potatoes by nematodes when using pieces of affected potatoes from 3 to 7 days after treatment with a 3% solution of the biological product with an exposure of 5 hours. In laboratory conditions, both methods of treatment of cut and whole tubers with the preparation can be used to test the effect of Nematophagin BT on potato stem nematode. Nematophagin BT showed nematicidal activity against potato stem nematode in laboratory conditions.
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Zeleneva, Yu V., Ph B. Gannibal, I. А. Kazartsev i V. P. Sudnikova. "Molecular Identification, Effector genes and Virulence of Isolates of <i>Parastagonospora nodorum</i> from Altai Krai (Russia)". Микология и фитопатология 57, nr 5 (1.09.2023): 362–71. http://dx.doi.org/10.31857/s0026364823050124.
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Septoria blotches represent some of the most harmful wheat diseases that encompass all grain-producing countries worldwide. They are caused mainly by fungi of the genera Parastagonospora and Zymoseptoria. The aims of the research were to analyze the nucleotide sequences of two phylogenetically informative DNA loci, ITS and tub2, of Parastagonospora nodorum isolates from the Altai Krai, to detect the presence of Tox1, Tox3, ToxA effector genes and to study the virulence of the isolates. Microscopic analysis of fragments of affected plant tissue was used for primary identification of the Septoria blotch. The causative agent from the studied plant samples was identified as P. nodorum. Fungal colonies cultivated on potato-glucose agar displayed a well-developed light brown velvety mycelium with dark periphery (mixed type) and numerous pycnidia exhibiting high sporulation capacity. Microbiological diagnostics were complemented by molecular genetic studies. Sequencing of ITS and tub2 loci isolates revealed complete genetic identity of all eight studied monoconidial isolates obtained from different samples. PCR-based detection of tree Tox-genes demonstrated that the only Tox3 was present in the geno-types of 80 tested P. nodorum monoconidial isolates. The ToxA and Tox1 genes were not found in the studied isolates. The virulence of P. nodorum isolates was evaluated in laboratory conditions using an isolated wheat leaves assay. Mixture of four isolates from spring wheat and one isolate from winter wheat, were characterized as virulent. When spring and winter wheat cultivars were infected with two isolates obtained from oats, pathogenic but avirulent properties were detected. The isolate from triticale was avirulent to winter wheat cultivars and virulent to spring wheat cultivars.
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Sokol, Ye I., K. V. Kolisnyk i T. V. Bernads’ka. "Evaluation of metrological characteristics of spectral analysis method for determining erythrocyte morphology". Технология и конструирование в электронной аппаратуре, nr 3-4 (2021): 45–49. http://dx.doi.org/10.15222/tkea2021.3-4.45.
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Spectral photometry is currently widely used for quantitative and qualitative analysis of biological molecules in medical biology. The method is based on the ability of molecules to absorb electromagnetic radiation. Modern clinical laboratory diagnostics extensively uses optical methods of analysis that rely on these physical properties of semitransparent objects, such as blood components. Knowing the absorption spectra of blood and its components, it is possible to quantify the concentration of all the components by solving the mathematical system of equations corresponding to these spectra. However, the existing methods of optical analysis of erythrocytes do not allow quantifying their geometric parameters, which may also indicate certain diagnostic signs and be used to analyze the clinical condition of the patient's body. The aim of this work is to evaluate the metrological characteristics of the newly developed method of determining the geometric parameters of erythrocytes, which combines spectral analysis and double annealing. The input data for the 3D imaging of erythrocytes were taken from the images of the sample both made in natural light and illuminated by a coherent light source with different wavelengths. The latter, after some additional image correlation, increases the reliability of the result. The calculation results on the errors and the measuring channel resolution of the digital interference microscope indicate an acceptable accuracy of the method. The accuracy of the three-dimensional image obtained by the proposed method is more than 20% higher than that of other known methods. This allows determining the informative geometric parameters of the structure of erythrocytes more accurately and using them to obtain additional clinical diagnostic characteristics of the patient's body.
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Drozd, O. M., M. Yu Zhuravel, O. Ye Naidionova, I. P. Lezhenina i N. Yu Polchaninova. "THE DETERMINATION OF LOCAL CHANGES IN THE SUPPORTING ECOSYSTEM SERVICE OF SOIL ON THE TERRITORY OF OIL AND GAS PRODUCTION". Ecological Safety and Balanced Use of Resources, nr 2(18) (3.12.2018): 15–25. http://dx.doi.org/10.31471/2415-3184-2018-2(18)-15-25.
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The temporary withdrawal of agricultural land for the construction or overhaul of wells and pipelines laying is, in essence, an interference with the natural soil-forming process, the result of which is a change in the implementation of the ecosystem functions of the soil and, consequently, ecosystem services of the soil.
The article analyses the influence of industrial activity and soils reclamation on the implementation of the supporting ecosystem service of soil. Such indicators as agrophysical, physico-chemical, chemical indices of soil, species composition, trophic structure and the state of the indicator groups of the invertebrates (rainworms, enchitrides, larvae of elaterids), the number of the microorganisms of the main ecofunctional and taxonomic groups (bacteria that absorb organic and mineral nitrogen, actinomycetes, microscopic fungi, oligotrophic bacteria), enzymatic activity and soil toxicity were selected as indicators of anthropogenic change. Four soil samples were taken at each experimental and background site for the reckoning of mesofauna (50×50×30 cm). Thus, 1 m² of land was surveyed on each experimental area. The final evaluation of the soil condition at different points was carried out using the integral index of the biological state of the soil (IIBS).
Following the research of the agro-ecological state of the soil on the territory of two rehabilitated sites of oil and gas production wells local changes in the supporting ecosystem service are defined within the spread of gray forest soil. It is established that the general unfavorable property of background and recultivated soils is high density indices. Unfavorable agrophysical properties determine the differentiation of the parameters of the analyzed indicators of the supporting ecosystem service of soil. The article proves the expediency of using the complex of the most informative biological indicators to assess the quality of reclamation and the state of reclaimed soils.
Rozprawy doktorskie na temat "Microscopie – Analyse informatique"
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Cazorla, Clément. "Analyse d'images en microscopie par réseaux de neurones dans un contexte frugal". Electronic Thesis or Diss., Université de Toulouse (2023-....), 2024. http://www.theses.fr/2024TLSES028.
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Dans ce manuscrit de thèse, nous explorons l'usage de réseaux de neurones dans un contexte frugal, c'est-à-dire avec peu de données d'entraînement, appliqué à des tâches d'analyse d'images de microscopie. Au cours de ces travaux, j'ai fourni un travail substantiel d'intégration dans des interfaces utilisateur ergonomiques. Celles-ci prennent la forme de plugins Napari, un logiciel open-source de visualisation d'images multi-dimensionnelles. Plus largement, ce travail permet de rapprocher les utilisateurs de microscopes et les technologies d'apprentissage profond, actuellement complexes à appréhender, et à implémenter, à travers des logiciels d'apprentissage interactifs. Les biologistes recourent de plus en plus à diverses modalités d'imagerie, dans le but d'accéder à de nouvelles sources d'information dans des contextes de recherche fondamentale comme applicative. Cette intensification de l'usage des microscopes a conduit à des volumes de données importants, dont l'analyse pose aujourd'hui de réelles questions techniques et scientifiques. Le traitement de ces données est bien souvent effectué de manière manuelle par des biologistes (comptage de cellules par exemple), induisant des problèmes de reproductibilité des résultats inter et intra opérateurs, mais aussi des temps de traitement parfois très importants. L'essor de l'apprentissage profond au cours des dernières années donne aujourd'hui accès à des possibilités d'analyse encore inatteignables il y a quelques années de cela. Néanmoins, à l'heure où les questions de consommation d'énergie et de stockage deviennent cruciales, ces approches posent certains problèmes. Le recueil de grandes quantités d'images et leur annotation sont coûteux et complexes. Leur fiabilité est parfois remise en cause, car ces modèles neuronaux sont fréquemment considérés comme difficiles, voire impossibles à interpréter. À l'heure actuelle, de nombreuses initiatives de mise en commun de modèles et de ressources de calculs, ainsi que de recherche sur l'interprétabilité de ces réseaux sont déployées, afin de les rendre accessibles à un plus large public. Cette thèse s'articule autour de deux grands axes de l'analyse d'images que sont la segmentation et la classification. Dans un premier temps, nous rappellerons l'état de l'art des méthodes d'analyse par apprentissage en microscopie, puis nous présenterons les méthodes frugales que nous avons développées pour ces deux tâches. Par la suite, nous présenterons leur intégration sous forme de plugins Napari open-source. Enfin, nous montrerons, à travers des exemples concrets de collaborations à la fois académiques et industrielles, l'intérêt de ces méthodes et les résultats qu'elles fournissentIn this thesis manuscript, we explore the use of neural networks in a frugal context, i.e. with little training data, applied to microscopy image analysis tasks. In the course of this work, I have carried out substantial integration work in ergonomic user interfaces. These take the form of plugins for Napari, an open-source software package for multi-dimensional image visualization. More broadly, this work brings microscope users and deep learning technologies, currently complex to grasp and implement, closer together through interactive learning software. Biologists are making increasing use of various imaging modalities, with the aim of accessing new sources of information in both basic and applied research contexts. This intensification in the use of microscopes has led to large volumes of data, the analysis of which today poses real technical and scientific questions. Data processing is often carried out manually by biologists (e.g. cell counting), leading to problems of inter- and intra-operator reproducibility of results, as well as processing times that can be very long. The development of deep learning over the last few years has opened up analysis possibilities that were unattainable just a few years ago. Nevertheless, at a time when energy consumption and storage are becoming crucial issues, these approaches pose certain problems. Collecting and annotating large quantities of images is costly and complex. Their reliability is sometimes called into question, as these neural models are frequently considered difficult, if not impossible, to interpret. Today, numerous initiatives are underway to pool models and computational resources, and to research the interpretability of these networks, in order to make them accessible to a wider audience. This thesis focuses on two main areas of image analysis : segmentation and classification. First, we will review the state of the art in learning-based analysis methods for microscopy, and then present the frugal methods we have developed for these two tasks. We will then present their integration as open-source Napari plug-ins. Finally, we'll use concrete examples from both academic and industrial collaborations to demonstrate the value of these methods and the results they deliver
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Bonnail, Nicolas. "Analyse des données, modélisation et commande pour la microscopie en champ proche utilisant des actionneurs piézoélectriques". Aix-Marseille 2, 2001. http://www.theses.fr/2001AIX22059.
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Dupé, François-Xavier. "Restauration et reconnaissance des formes dans des images avec bruit de Poisson : application à l'analyse des neurones en microscopies de fluorescence". Caen, 2010. http://www.theses.fr/2010CAEN2002.
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Dans le cadre de l'étude du cerveau, les biologistes et les médecins s'intéressent à de petites excroissances sur les dendrites appelées épines dendritiques. Ces épines jouent un rôle important au niveau des transmissions synaptiques. Elles sont observées par fluorescence avec un microscope confocal. Les images acquises sont difficiles à exploiter car elles sont 1) dégradées par le flou dû aux limites de la diffraction et du bruit, 2) les épines présentent une grande diversité morphologique et 3) une dendrite peut posséder une densité importante d'épines. Cette thèse se décompose donc en trois parties : la première partie présente un cadre théorique d'optimisation aboutissant à des algorithmes de déconvolution sous bruit de Poisson. La deuxième partie concerne la comparaison de formes par leur morphologie avec des noyaux sur graphes. La troisième partie propose une plateforme d'exploitation d'images d'épines pour obtenir automatiquement des informations morphologiques sur ces épinesWhile studying the brain, biologists and doctors focus on some small protrusions on the dendrites which go by the name of dendritic spines. These spines play an important role in the synaptic transmission process. They are observed using a fluorescent confocal microscope. Observed images are hard to exploit because 1) they are degraded by diffraction-related blur and noise, 2) they present a large morphological diversity and 3) one dendrite may show an important density of spines. This thesis is then divided into three parts : the first part presents a theoretical optimization framework that is then applied to deconvolution under Poisson noise. The second part considers shape comparison using morphological information by graph kernels. The third part proposes a framework that deploys the image analysis tools developed in the previous chapters to get automatically morphological information about the observed spines
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Bruch, Jean-Frédéric. "Analyse du cordon ombilical par microscopie informatisée "HOME" (Highly Optimized Microscope Environment) : algorithmes de segmentation et de paramétrisation, ergonomie des interfaces homme-machine, applications médicales concrètes". Paris 12, 1996. http://www.theses.fr/1996PA120080.
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Ce travail traite de la mise au point d'un nouvel outil d'analyse morphometrique du cordon ombilical par la technique de microscopie informatisee home pour highly optimized microscope environment, afin de mieux caracteriser et comprendre les malies funiculaires dans les maladies vasculaires de la grossesse. On etablit un principe d'analyse angio-architecturale selon trois niveaux: (i) structural (anatomie, developpement) ; (ii) fonctionnel (hemodynamique, regulation paracrine ; (iii) relations structure/fonction (biomecanique, modelisation). Cette etape aboutit a (i) la specification de parametres geometriques vasculaires ; (ii) la conception et l'implantation de deux logiciels de segmentation et parametrisation: cord-home et bubble-home (graphique et image) ; (iii) une evaluation clinique. On etudie (i) le developpement normal du cordon ; (ii) le retard de croissance intra-uterin avec anomalies hemodynamiques: (iii) l'artere ombilicale unique versus deux arteres. Les resultats permettent d'identifier trois types d'etats: (i) developpement vasculaire ombilical normal, (ii) hypo-developpement ; (iii) hyper-developpement. Cette etude montre l'importance de: (i) l'analyse conceptuelle prealable a la construction logicielle, (ii) l'ergonomie de l'interface homme-machine ; (iii) d'une pathologie du developpement vasculaire ombilical, soulignant le role potentiel du cordon dans la genese des anomalies anatomiques de la microcirculation placentaire. Les deux approches d'ingenierie et transfert sont ici mises en coherence pour poser les jalons d'une nouvelle ere diagnostique comprehensive en placentologie
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Andronov, Leonid. "Development of advanced methods for super-resolution microscopy data analysis and segmentation". Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAJ001.
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Parmi les méthodes de super-résolution, la microscopie par localisation de molécules uniques se distingue principalement par sa meilleure résolution réalisable en pratique mais aussi pour l’accès direct aux propriétés des molécules individuelles. Les données principales de la microscopie par localisation sont les coordonnées des fluorochromes, un type de données peu répandu en microscopie conventionnelle. Le développement de méthodes spéciales pour le traitement de ces données est donc nécessaire. J’ai développé les logiciels SharpViSu et ClusterViSu qui permettent d’effectuer les étapes de traitements les plus importantes, notamment une correction des dérives et des aberrations chromatiques, une sélection des événements de localisations, une reconstruction des données dans des images 2D ou dans des volumes 3D par le moyen de différentes techniques de visualisation, une estimation de la résolution à l’aide de la corrélation des anneaux de Fourier, et une segmentation à l’aide de fonctions K et L de Ripley. En plus, j’ai développé une méthode de segmentation de données de localisation en 2D et en 3D basée sur les diagrammes de Voronoï qui permet un clustering de manière automatique grâce à modélisation de bruit par les simulations Monte-Carlo. En utilisant les méthodes avancées de traitement de données, j’ai mis en évidence un clustering de la protéine CENP-A dans les régions centromériques des noyaux cellulaires et des transitions structurales de ces clusters au moment de la déposition de la CENP-A au début de la phase G1 du cycle cellulaireAmong the super-resolution methods single-molecule localization microscopy (SMLM) is remarkable not only for best practically achievable resolution but also for the direct access to properties of individual molecules. The primary data of SMLM are the coordinates of individual fluorophores, which is a relatively rare data type in fluorescence microscopy. Therefore, specially adapted methods for processing of these data have to be developed. I developed the software SharpViSu and ClusterViSu that allow for most important data processing steps, namely for correction of drift and chromatic aberrations, selection of localization events, reconstruction of data in 2D images or 3D volumes using different visualization techniques, estimation of resolution with Fourier ring correlation, and segmentation using K- and L-Ripley functions. Additionally, I developed a method for segmentation of 2D and 3D localization data based on Voronoi diagrams, which allows for automatic and unambiguous cluster analysis thanks to noise modeling with Monte-Carlo simulations. Using advanced data processing methods, I demonstrated clustering of CENP-A in the centromeric regions of the cell nucleus and structural transitions of these clusters upon the CENP-A deposition in early G1 phase of the cell cycle
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Marak, Laszlo. "On continuous maximum flow image segmentation algorithm". Phd thesis, Université Paris-Est, 2012. http://tel.archives-ouvertes.fr/tel-00786914.
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In recent years, with the advance of computing equipment and image acquisition techniques, the sizes, dimensions and content of acquired images have increased considerably. Unfortunately as time passes there is a steadily increasing gap between the classical and parallel programming paradigms and their actual performance on modern computer hardware. In this thesis we consider in depth one particular algorithm, the continuous maximum flow computation. We review in detail why this algorithm is useful and interesting, and we propose efficient and portable implementations on various architectures. We also examine how it performs in the terms of segmentation quality on some recent problems of materials science and nano-scale biology
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Fadili, Jalal M. "Une exploration des problèmes inverses par les représentations parcimonieuses et l'optimisation non lisse". Habilitation à diriger des recherches, Université de Caen, 2010. http://tel.archives-ouvertes.fr/tel-01071774.
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Ce mémoire résume mon parcours de recherche lors des dix dernières années. Ces travaux de recherche se trouvent à la croisée des chemins entre les mathématiques appliquées et le traitement du signal et des images. Ils s'articulent autour du triptyque: (i) modélisation stochastique-estimation statistique; (ii) analyse harmonique computationnelle-représentations parcimonieuses; (iii) optimisation. Ces trois piliers constituent le socle théorique de mes activités pour développer des approches originales capables de résoudre des problèmes classiques en traitement d'images comme les problèmes inverses en restauration et reconstruction, la séparation de sources, la segmentation, la détection, ou encore la théorie de l'échantillonnage compressé (compressed sensing). Ces travaux ont été appliqués à plusieurs modalités d'imagerie comme l'imagerie médicale et biomédicale (IRM fonctionnelle, échographie, microscopie confocale), le contrôle non destructif et l'imagerie astronomique.
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Sotomayor, Gonzalez Miguel. "Analisi e sviluppo di una procedura di post-processing per immagini acquisite da telecamere in toni di grigio". Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/20459/.
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Ai giorni nostri, la Microscopia è diventata una disciplina fortemente legata all’acquisizione di immagini digitali, in questo scenario, disporre di una telecamera in grado di acquisire immagini a colori, ad esempio una telecamera RGB, diventa fondamentale per varie discipline della Microscopia. Tuttavia, nel campo della Microscopia a Fluorescenza, dove si perde la correlazione cromaticità-tessuto e dove si contano fotoni emessi da sonde fluorescenti legate a particolari compartimenti sub-cellulari di interesse, sono tipicamente utilizzate telecamere in toni di grigio, molto più sensibili di quelle a colori. Non sempre nei laboratori è possibile avere a disposizione tutte le attrezzature necessarie, c’è quindi bisogno di poter sfruttare, dove possibile, tutte le potenzialità delle attrezzature già disponibili per l’acquisizione d’immagine in toni di grigio, poiché, utilizzando in maniera intelligente dei filtri di plastica, tipicamente presenti microscopio per selezionare fotoni d'interesse a seconda della sonda fluorescente utilizzata, si potrebbero ricostruire immagini a colori partendo da una serie di tre immagini acquisite in scala di grigio, utilizzando in sequenza un filtro per il range di lunghezze d’onda del Rosso (R), del Verde (G) e del Blu (B). Ciò permetterebbe l’opportunità di utilizzare immagini a colori e sfruttare l’attrezzatura già presente all’interno di un laboratorio, non appositamente sviluppata, rendendo superfluo l’uso o acquisto di strumentazione dedicata all’acquisizione di immagini a colori.
In questo lavoro di Tesi, abbiamo verificato la possibilità di acquisizione di immagini “fake-RGB” utilizzando un microscopio confocale dotato di telecamera in toni di grigio. Abbiamo quindi definito una metrica quantitativa, il Delta E normalizzato, per poter confrontare immagini “fake-RGB” con immagini a colori, realmente acquisite con una telecamera a colori, ed abbiamo discusso limiti e possibilità fornite dalla strumentazione.
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Conard, Didier. "Traitement d'images en analyse de défaillances de circuits intégrés par faisceau d'électrons". Grenoble INPG, 1991. http://tel.archives-ouvertes.fr/tel-00339510.
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Cette thèse présente l'étude et la réalisation d'un système automatique et intégré d'analyse de défaillances de circuits VLSI par faisceau d'électrons. Le principe d'analyse consiste a comparer les images représentant en contraste de potentiel le fonctionnement interne du circuit défaillant a celles d'un circuit de référence. L'application de cette technique de test a des circuits dont la structure détaillée est inconnue, a nécessité le développement d'un outil automatique permettant d'extraire les différences de contraste sur la totalité du circuit. L'automatisation s'est heurtée aux problèmes d'alignement entre les images a comparer. Une technique de reconnaissance des formes, basée sur la détection des coins, a été mise en œuvre pour s'affranchir de ces problèmes. Ces travaux ont été valides par une étude expérimentale menée sur des microprocesseurs 68000
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Ndiaye, Ismaïla Abderhamane. "Résolution de problèmes multicritères (durée/sécurité) pour la conception de plans d'évacuation de personnes". Thesis, Tours, 2016. http://www.theses.fr/2016TOUR4001/document.
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Les travaux présentés dans cette thèse visent à proposer des méthodes de routage d’une population de masse à travers un réseau perturbé dont les données varient dans le temps pour l’aide à la conception de plan d’évacuation. Ce problème s’illustre parfaitement en cas de catastrophe d’origine humaine ou naturelle où les populations (potentiellement) impactées par ces sinistres doivent quitter leur lieux de vie pour une période pouvant aller d’un à plusieurs jours. Dans la littérature, ces routages de masse sont souvent modélisés comme des problèmes de flots dynamiques dont l’objectif est de minimiser la durée globale du transfert des individus depuis un certain nombre de points de départs dangereux vers des points d’arrivé sûrs. Toutefois, peu de travaux prennent en compte la notion de sécurité durant ce routage et encore moins le déploiement d’agents (policiers, sapeur-pompiers, ambulanciers,...) pouvant sécuriser et/ou faciliter le déplacement des personnesThe work presented in this thesis aims to propose methods for routing a mass population through a disturbed network whose data vary over time. This problem can be illustrated by disasters due to humans or natural events where people (potentially) affected have to leave their living places for a period of one to several days. In the literature, mass routing are often modeled as dynamic flow problems whose objective is to minimize the overall duration of the evacuation process from a set of gathering points towards another set of shelter locations. However few papers take into account the concept of safety during this routing nor deploying task forces that can secure or facilitate this process. In this context, the safety security can be seen as a danger affecting the quality of life of people we organize the trip. In this context, the safety can be seen as a danger that influence the health of the people we are trying to evacuate. Indeed, this hazardous event can be related to a radioactive cloud, a fire, a tsunami, an earthquake or a flooding which make some of paths becoming dangerous or less usable by evacuees
Książki na temat "Microscopie – Analyse informatique"
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Mutter, Walter P. Urinalysis. Redaktor Christopher G. Winearls. Oxford University Press, 2015. http://dx.doi.org/10.1093/med/9780199592548.003.0006.
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Physicians have examined urine for over 6000 years. Urine microscopy was first employed to diagnose kidney disease in the seventeenth century and remains an indispensable tool. The value of urinalysis for diagnosis and management of renal and genitourinary disease is well accepted. Urinalysis aids in the diagnosis of renal disease especially in cases when a renal biopsy is not immediately available or is contraindicated. It is most informative when done by the treating physician with knowledge of the clinical context. Inspection is done by eye. Routine chemical analysis is done by dipstick but urine microscopy is essential for it may reveal abnormalities even when chemical evaluation is normal. Dysmorphic red cells, red cell casts, white blood cells, renal cells, and specific crystals may be diagnostically important. Urinalysis and microscopy can narrow the differential diagnosis faster than many more complex tests are able to.
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Hawkes, Peter W. Advances in Electronics and Electron Physics (Advances in Imaging and Electron Physics). Academic Press, 1990.
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Hawkes, Peter W. Advances in Electronics and Electron Physics (Advances in Imaging and Electron Physics). Academic Press, 1988.
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Hawkes, Peter W. Advances in Electronics and Electron Physics (Advances in Imaging and Electron Physics). Academic Press, 1990.
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Hawkes, Peter W. Advances in Electronics and Electron Physics (Advances in Imaging and Electron Physics). Academic Press, 1991.
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Hawkes, Peter W. Advances in Electronics and Electron Physics (Advances in Imaging and Electron Physics). Academic Press, 1986.
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Hawkes, Peter W. Advances in Electronics and Electron Physics (Advances in Imaging and Electron Physics). Academic Press, 1985.
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Hawkes, Peter W. Advances in Electronics and Electron Physics (Advances in Imaging and Electron Physics). Academic Press, 1989.
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Hawkes, Peter W. Advances in Electronics and Electron Physics (Advances in Imaging and Electron Physics). Academic Press, 1986.
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Hawkes, Peter W. Advances in Electronics and Electron Physics (Advances in Imaging and Electron Physics). Academic Press, 1986.
Znajdź pełny tekst źródłaCzęści książek na temat "Microscopie – Analyse informatique"
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Spence, Jackie. "Plant histology". W Plant Cell Biology, 189–206. Oxford University PressOxford, 2001. http://dx.doi.org/10.1093/oso/9780199638666.003.0009.
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Abstract The microscope is one of the most important instruments used in biological research and it has contributed much to our knowledge of morphology and cell dynamics. Over the past ten years there have been many advances in light microscopical techniques including the development of the confocal microscope and improved image analysis software. However the need for simpler analytical techniques has certainly not decreased. Today molecular biologists and biochemists often require the light or fluorescence microscope to analyse gene expression patterns, mutant phenotypes, and structure-function relationships (1), and, although most laboratories have access to a simple light and fluorescence micro scope, not all laboratories have the expertise in microscopical techniques. The aim of this chapter is to introduce the non-microscopist to some of the more simple, but no less informative, histological techniques for the study of plant tissues.
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Mohite Ramesh, D., Trilok Ranjan Mudgal i Krishan Kumar Kataria. "An Application of Magnetic and Geochemical Techniques to Determine Pollution Load In Leafy Vegetables in the Industrial Area". W Advances in Environmental Engineering and Green Technologies, 313–25. IGI Global, 2023. http://dx.doi.org/10.4018/978-1-6684-9231-4.ch017.
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A study is carried out to evaluate the heavy metals contamination in leafy vegetables in Navi Mumbai. Samples of four leafy vegetables—spinach, radish, mayalu, and red mat—were collected from Navi Mumbai. Heavy metals are determined in washed and unwashed bulk samples using a XRF spectrometer by the turbo quant-powder method. For visual identification of natural and anthropogenic particulates, geochemical, magnetic measurements, and scanning electron microscopy analysis of some washed and unwashed vegetable samples are carried out. The observed data when compared with the data of WHO limit, Fe, and Pb concentration were found to be more than permissible limits whereas the concentrations of Cu, Zn, Mn, and Ni were lower. Correlation coefficients between the magnetic susceptibility and concentrations of various elements in vegetable samples are computed. SEM images show the presence of a significant amount of magnetic spherules. Combined study of magnetic and chemical analyses provides informative results about shape, size, and surface structure of the particles contained in vegetables.
Streszczenia konferencji na temat "Microscopie – Analyse informatique"
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Xie, X. Sunney, i Robert C. Dunn. "Fluorescence Spectroscopy on a Single Molecule Basis with a Near-field Spectrometer". W Laser Applications to Chemical Analysis. Washington, D.C.: Optica Publishing Group, 1994. http://dx.doi.org/10.1364/laca.1994.thd.4.
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Recent advances in near-field optical microscopy [1] have offered exciting possibilities for conducting molecular spectroscopy at the nanometer dimension. In particular, fluorescence detection of single chromophores and single proteins containing several chromophores have been achieved using this technique[2][3]. For chemical analysis and biological applications, fluorescence measurements with near-field optics will be particularly informative, providing spectroscopic information not accessible with other scanning probe techniques, such as SEM, STM and AFM.
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Demarest, James J., i Hong-Ying Zhai. "Highly Automated Transmission Electron Microscopy Tomography for Defect Understanding". W ISTFA 2011. ASM International, 2011. http://dx.doi.org/10.31399/asm.cp.istfa2011p0137.
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Abstract Imaging tomography by transmission electron microscopy (TEM) is a technique which has been growing in popularity in recent years, yet it has not been widely applied to semiconductor defect studies and root cause determination [1- 3]. In part this is due to the complex equipment, computing needs, and microscope time required to generate the various images which ultimately compose the data set. However, the latest generation of TEMs—with their high level of stability and automation—are greatly reducing the resource needs to create high quality and informative movies of defects rotating about a central axis. One significant advance is the reduction in time required to fabricate a sample and perform the data acquisition by TEM. Today’s microscopes allow for sample fabrication to take place in a few hours or less and can acquire more than 100 images in about an hour at different sample tilt conditions with minimal analyst intervention. This paper describes using automated TEM sample preparation with dual beam focused ion beams (previously reported [4]) in conjunction with automated tomography software on a state-of-the-art TEM. By using an advanced tomography holder ±70° of tilt can be obtained. This is a powerful way to view defects as the failure can be viewed through more than 90° of rotation. Consequently a more complete understanding of the failure site can be obtained over a typical single projection TEM image. This can greatly facilitate root cause determination in a timely manner.
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Leavers, V. F., i M. D. Hanlon. "Establishment of the Accuracy and Consistency of Using Automatic Image Analysis to Classify Wear Debris Particles". W World Tribology Congress III. ASMEDC, 2005. http://dx.doi.org/10.1115/wtc2005-64385.
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Wear debris particle analysis is an equipment health monitoring technique used to identify possible failure modes in various engine components. One of the first stages in the analysis involves the examination under a microscope of particles collected from the component’s lubrication system on magnetic drain plugs and filters. However, the subjectivity of technicians’ judgements means that diagnosis may not be consistent between technicians. A software tool capable of automatically classifying the images of wear debris particles has been developed and tested using an 800-image database. It is shown that using automatic image analysis for the classification of wear debris particle images is more consistent, accurate and informative when compared to the classifications assigned by wear debris experts.
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Kim, Beomjun, Seonghee Park, Juhyun Kim, Moonhyun Lee, Seongjun Cho, Seokjun Won i Jinsung Kim. "Failure Analysis Approaches for Stacking Fault Defects in FinFET Devices". W ISTFA 2019. ASM International, 2019. http://dx.doi.org/10.31399/asm.cp.istfa2019p0313.
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Abstract In this paper, the stacking fault defects in FinFETs are described as the root cause of the PLL failure. Failure analysis approaches such as photon emission microscopy and nano probing were applied to pinpoint the exact stacking fault location in even transistor level and High resolution TEM confirmed the stacking fault defects in the Fin which was isolated by nano probing. RX local density was confirmed as the key factor in stacking fault generation by TCAD simulation. RX new mask with dummy addition was made to mitigate stress and was confirmed to be effective to reduce the compressive strain at the channel in FinFETs by Geometric Phase Analysis (GPA) which provided sufficiently practical local strain measurement data. The GPA techniques demonstrated here are informative for process improvement and failure analysis in FinFET devices. Keywords – Stacking Fault, Geometric Phase Analysis
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Al Hamad, Mohammed, Denis Klemin, Mark Ma Shouxiang i Wael Abdallah. "Digitally Derived Capillary Pressure Data for Reservoir Evaluation". W Middle East Oil, Gas and Geosciences Show. SPE, 2023. http://dx.doi.org/10.2118/213776-ms.
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Abstract Capillary pressure (Pc) is one of the fundamental parameters in formation evaluation. Currently, three methods are routinely used for Pc measurement; i.e., mercury injection, centrifuge, and porous plate. All three methods require testing of fluid displacement at capillary equilibrium conditions, an often-challenging condition to obtain, especially in low-quality rock samples. In this study, the ability to derive Pc data was investigated using digital rock (DR) physics techniques. Two sister carbonate outcrop samples were prepared. The samples were initially analyzed using thin-section analysis technique. The Pc measurements were then performed using methods of porous plate and mercury injection capillary pressure (MICP). After that, the samples were sub-cored, mounted in a unique computed tomography (CT) cell, scanned with a high-resolution micro-CT device at a confining stress of 800 psig, and analyzed digitally with a scanning electron microscope for data interpretation. Comparing the physically measured to the digitally simulated data, matches of pore throat sizes in terms of trends and peaks were obtained, including entry pressure, which validated and confirmed the quality of the constructed DR models. Using the established digital models of the rock samples, the Pc behavior was simulated. The results showed trend and connate water saturation matches with the experimental measurements. The results of this study demonstrate that the digitally generated Pc data obtained using the unique micro-CT polyetheretherketone (PEEK) high-pressure cell match the experimental data, opening new ways of generating Pc data quickly and reliably. With the developed DR technologies, performing special core analysis tests much faster becomes a reality without concerns for test equilibrium conditions, while also providing informative insights into the pore structure of the rock samples.
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Jumanov, I. I., i R. A. Safarov. "Optimization of recognition of micro-objects based on the use of morphometric characteristics of images". W III All-Russian Scientific Conference with International Participation "Science, technology, society: Environmental engineering for sustainable development of territories". Krasnoyarsk Science and Technology City Hall, 2022. http://dx.doi.org/10.47813/nto.3.2022.6.93-108.
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Constructive approaches, principles and methods of identification, recognition and classification of micro-objects based on the use of neural networks and mechanisms for extracting morphometric characteristics of images have been developed. Information processing technology based on obtaining images of micro-objects from a photo, video camera, digital microscope is proposed. A technique has been developed for interactive measurement of the size of micro-objects, counting, determining the structure, conducting statistical analysis, isolating and segmenting fragments, selecting informative points, recognizing and classifying images. A computational scheme for preliminary processing of images is built, including mechanisms for texture, contour segmentation, detection, and regulation of variables. Algorithms for learning neural networks with setting variables within the limits of permissible values, taking into account the properties of nonstationarity of image points, have been built. The effectiveness of learning algorithms combined with neural network dynamic models with mechanisms for regulating linear, nonlinear, compositional connections of neurons between network layers has been investigated. The study was carried out according to the criterion of the percentage of correct recognition. A software package for visualization, recognition, classification of images of pollen grains has been developed and implemented, which has been tested under conditions of a priori insufficiency, uncertainty and nonstationarity.
Raporty organizacyjne na temat "Microscopie – Analyse informatique"
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Glazer, Itamar, Alice Churchill, Galina Gindin i Michael Samish. Genomic and Organismal Studies to Elucidate the Mechanisms of Infectivity of Entomopathogenic Fungi to Ticks. United States Department of Agriculture, styczeń 2013. http://dx.doi.org/10.32747/2013.7593382.bard.
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The overall goal of this research was to elucidate the factors affecting early development of Metarhizium spp. (previously named M. anisopliae) on ticks or tick cuticle extracts and the molecular basis of these early infection processes. The original objectives were: 1. Characterize the pre-penetration events (adhesion, germination and appressorium formation) of spores of M. anisopliae strains with high or low virulence during tick infection. 2. Create GFP-expressing strains of M. anisopliae tick pathogens having high and low virulence to compare their progress of infection by microscopy. 3. Use microarray analyses, primarily with existing M. anisopliae EST sequences in GenBank, to identify and characterize fungal genes whose expression is regulated in response to host cuticle extracts. Objective 3 was later modified (as approved by BARD) to use RNAseq to characterize the early stages of fungal gene expression during infection of intact host cuticles. This new method provides a massively larger and more informative dataset and allows us to take advantage of a) recently published genomes of Metarhizium robertsii and M. acridum for RNAseq data analysis, and b) newly developed and highly efficient cDNA sequencing technologies that are relatively low cost and, therefore, allow deep sequencing of multiple transcriptome samples. We examined pre-penetration and penetration events that differentiate high and low virulence strains of Metarhizium spp., focusing on spore adhesion, germination, appressorium formation, and penetration of tick integuments. Initiation of fungal infection was compared on susceptible and resistant tick species at different tick developmental stages. In vitro studies comparing the effects of protein and fatty acid profiles from tick cuticle extracts demonstrated that resistant tick cuticles contain higher concentrations of specific lipids that inhibit fungal development than do susceptible tick cuticles, suggesting one mechanism of Ixodidae resistance to fungal entomopathogens (Objective 1). We used molecular markers to determine that the three M. anisopliae strains from Israel that we studied actually were three distinct species. M. brunneum is highly virulent against the tick Rhipicephalus annulatus, M. pingshaense and M. robertsii are intermediate in virulence, and M. majus is of low virulence. We transformed all four Metarhizium species to express GFP and used them in pathogenicity assays against diverse tick species. Key findings were that a) resistant ticks inhibit Metarhizium infection prior to hemocoel invasion by reducing fungal viability on the cuticle surface (Objective 2), as was supported by the in vitro studies of Objective 1, and b) Metarhizium kills susceptible ticks after cuticle penetration but prior to hemocoel colonization. Transcriptome studies of the most virulent species, M. brunneum, are in progress and include analyses of ungerminated conidia and conidia germination and development on a low nutrient medium or on susceptible R. annulatus exoskeleton (Objective 3). We anticipate these studies will contribute to identifying fungal genetic factors that increase virulence and speed of kill and may help reveal tick chemistries that could be included in biocontrol formulations to increase efficacy. Methodologies developed to screen tick cuticle extracts for ability to support conidia germination and development may help in the selection of wild fungi with increased virulence against resistant ticks. The overall knowledge gained should contribute not only to the improvement of tick control but also to the control of other blood-sucking arthropods and related plant pests. Use of bio-based agents for controlling arthropods will contribute to a healthier, more sustainable environment and serve a growing number of organic food farmers.