Academic literature on the topic 'Retina face'
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Journal articles on the topic "Retina face"
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Dunlop, S. A., S. R. Moore, and L. D. Beazley. "Changing patterns of vasculature in the developing amphibian retina." Journal of Experimental Biology 200, no. 18 (1997): 2479–92. http://dx.doi.org/10.1242/jeb.200.18.2479.
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Patterns of vascularisation were examined in whole-mounted retinae from tadpole stages to adulthood in the tree frog Litoria moorei using perfusion with Indian ink. Changing cell densities in the underlying ganglion cell layer were studied in a parallel Cresyl-stained series. Throughout development, the vasculature was pan-retinal and the hyaloid vessel was prominent. In early tadpole stages, capillaries were arranged as a honeycomb, and their number increased at a rate sufficient to maintain high densities in the face of increasing retinal area; major arteries and veins condensed within the capillary network. By early post-metamorphic life, the retinal vasculature was remodelled by the loss of four-fifths of the capillaries; the reduction in their density was far greater than could be accounted for by continuing retinal growth. This loss resulted in a change from the honeycomb appearance to one with largely parallel vessels linked by fewer connecting ones, an arrangement that became increasingly pronounced. In post-metamorphic life, the number of branch points increased such that their density decreased only slightly in the face of considerable increases in retinal area. The density of branch points varied across the retina and changed with age. Initially, the vasculature was most dense centrally, but by mid-larval life densities were highest in two patches located in the mid-temporal and mid-nasal retina. Thereafter, the vasculature increasingly assumed gradients resembling an area centralis and visual streak, a profile that survived the vascular remodelling. The development of density gradients in the vasculature preceded that of cells in the ganglion cell layer, the latter appearing only following metamorphosis. However, in post-metamorphic life, the topographies of the retinal vasculature and cells in the ganglion cell layer were closely related.
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Pi, Shaohua, Tristan T. Hormel, Bingjie Wang, et al. "Volume-based, layer-independent, disease-agnostic detection of abnormal retinal reflectivity, nonperfusion, and neovascularization using structural and angiographic OCT." Biomedical Optics Express 13, no. 9 (2022): 4889. http://dx.doi.org/10.1364/boe.469308.
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Optical coherence tomography (OCT) is widely used in ophthalmic practice because it can visualize retinal structure and vasculature in vivo and 3-dimensionally (3D). Even though OCT procedures yield data volumes, clinicians typically interpret the 3D images using two-dimensional (2D) data subsets, such as cross-sectional scans or en face projections. Since a single OCT volume can contain hundreds of cross-sections (each of which must be processed with retinal layer segmentation to produce en face images), a thorough manual analysis of the complete OCT volume can be prohibitively time-consuming. Furthermore, 2D reductions of the full OCT volume may obscure relationships between disease progression and the (volumetric) location of pathology within the retina and can be prone to mis-segmentation artifacts. In this work, we propose a novel framework that can detect several retinal pathologies in three dimensions using structural and angiographic OCT. Our framework operates by detecting deviations in reflectance, angiography, and simulated perfusion from a percent depth normalized standard retina created by merging and averaging scans from healthy subjects. We show that these deviations from the standard retina can highlight multiple key features, while the depth normalization obviates the need to segment several retinal layers. We also construct a composite pathology index that measures average deviation from the standard retina in several categories (hypo- and hyper-reflectance, nonperfusion, presence of choroidal neovascularization, and thickness change) and show that this index correlates with DR severity. Requiring minimal retinal layer segmentation and being fully automated, this 3D framework has a strong potential to be integrated into commercial OCT systems and to benefit ophthalmology research and clinical care.
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Agarwal, Sagar, Madhurima A. Nayak, Saurabh Luthra, and Shweta Parakh. "Acute macular neuroretinopathy following Valsalva manoeuvre: an insight into the pathophysiology." BMJ Case Reports 17, no. 5 (2024): e256685. http://dx.doi.org/10.1136/bcr-2023-256685.
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Acute macular neuroretinopathy (AMN) affects the outer retina and is most likely induced by non-inflammatory ischaemia of the retinal deep capillary plexus and choriocapillaris. A man in his early 20s developed Valsalva retinopathy following weightlifting at the gym and presented with blurring of vision in the left eye 1 month after the initial retinal haemorrhages had resolved. A diffuse, purplish, donut-shaped, perifoveal lesion was seen on funduscopy and was well defined by an optical coherence tomography angiography (OCTA) en face image in the left eye. Outer retinal changes on optical coherence tomography (OCT) and a dense co-localised scotoma on a visual field (VF) examination confirmed the diagnosis of AMN, and the patient was started on a tapering dose of oral steroids. Improvement was seen in OCT, OCTA and VF during the 6-month follow-up visit. The use of OCTA en face imaging enabled the accurate identification of the lesion in the affected layers of the retina.
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Katsuyama, Atsuko, Sentaro Kusuhara, Shun-Ichiro Asahara, et al. "En face slab optical coherence tomography imaging successfully monitors progressive degenerative changes in the innermost layer of the diabetic retina." BMJ Open Diabetes Research & Care 8, no. 1 (2020): e001120. http://dx.doi.org/10.1136/bmjdrc-2019-001120.
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ObjectiveTo evaluate the usefulness of en face slab optical coherence tomography (OCT) imaging for monitoring diabetic retinal neurodegeneration with supporting animal experimental data.Research design and methodsWe retrospectively examined 72 diabetic eyes over 3 years using Cirrus-HD OCT. Two-dimensional en face slab OCT images of the innermost retina were reconstructed and graded according to the ratio of dark area to total area, and relative red, green, and blue color area ratios were calculated and used as indexes for each en face slab OCT image. Values from en face OCT images were used for statistical analyses. To obtain insight into the pathogenesis of diabetic retinal neurodegeneration, we used the InsPr-Cre;Pdk1flox/flox diabetic mouse model.ResultsBoth OCT grade and relative red color area ratio significantly increased with the advancing stage of diabetic retinopathy (p=0.018 and 0.006, respectively). After a mean follow-up period of 4.6 years, the trend was unchanged in the analyses of 42 untreated eyes (p<0.001 and 0.001, respectively). Visual acuity showed a weak but significant negative correlation with the red color ratio on en face slab OCT images, but central retinal thickness did not exhibit a clinically meaningful correlation with values obtained from en face slab OCT images. Immunohistochemical analyses of InsPr-Cre;Pdk1flox/flox diabetic mice demonstrated the loss of ganglion axon bundles and thinning of laminin without apparent retinal vascular change at the age of 20 weeks.ConclusionsEn face slab OCT imaging would be a novel useful modality for the assessment of diabetic retinal neurodegeneration as it could detect subtle optical changes occurring in the innermost retina in diabetic eyes. Our animal experimental data suggest that dark areas observed on en face slab OCT images might be the impairment of the extracellular matrix as well as neurons.
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Alsalloum, Almaqdad, Ekaterina Gornostal, Natalia Mingaleva, et al. "A Comparative Analysis of Models for AAV-Mediated Gene Therapy for Inherited Retinal Diseases." Cells 13, no. 20 (2024): 1706. http://dx.doi.org/10.3390/cells13201706.
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Inherited retinal diseases (IRDs) represent a diverse group of genetic disorders leading to progressive degeneration of the retina due to mutations in over 280 genes. This review focuses on the various methodologies for the preclinical characterization and evaluation of adeno-associated virus (AAV)-mediated gene therapy as a potential treatment option for IRDs, particularly focusing on gene therapies targeting mutations, such as those in the RPE65 and FAM161A genes. AAV vectors, such as AAV2 and AAV5, have been utilized to deliver therapeutic genes, showing promise in preserving vision and enhancing photoreceptor function in animal models. Despite their advantages—including high production efficiency, low pathogenicity, and minimal immunogenicity—AAV-mediated therapies face limitations such as immune responses beyond the retina, vector size constraints, and challenges in large-scale manufacturing. This review systematically compares different experimental models used to investigate AAV-mediated therapies, such as mouse models, human retinal explants (HREs), and induced pluripotent stem cell (iPSC)-derived retinal organoids. Mouse models are advantageous for genetic manipulation and detailed investigations of disease mechanisms; however, anatomical differences between mice and humans may limit the translational applicability of results. HREs offer valuable insights into human retinal pathophysiology but face challenges such as tissue degradation and lack of systemic physiological effects. Retinal organoids, on the other hand, provide a robust platform that closely mimics human retinal development, thereby enabling more comprehensive studies on disease mechanisms and therapeutic strategies, including AAV-based interventions. Specific outcomes targeted in these studies include vision preservation and functional improvements of retinas damaged by genetic mutations. This review highlights the strengths and weaknesses of each experimental model and advocates for their combined use in developing targeted gene therapies for IRDs. As research advances, optimizing AAV vector design and delivery methods will be critical for enhancing therapeutic efficacy and improving clinical outcomes for patients with IRDs.
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De bats, Flore, Benjamin Wolff, Vivien Vasseur, et al. "“En-Face” Spectral-Domain Optical Coherence Tomography Findings in Multiple Evanescent White Dot Syndrome." Journal of Ophthalmology 2014 (2014): 1–6. http://dx.doi.org/10.1155/2014/928028.
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Purpose. The recent use of “en-face” enhanced-depth imaging spectral-domain optical coherence tomography (EDI SD-OCT) helps distinguish the retinal layers involved in the physiopathology of multiple evanescent white dot syndrome (MEWDS).Methods. Four patients presenting with MEWDS underwent a comprehensive ocular examination including C-scan (“en-face”) EDI SD-OCT at the initial visit and during follow-up.Results. C-scans combined with the other multimodal imaging enabled the visualization of retinal damage. Acute lesions appeared as diffuse and focal disruptions occurring in the ellipsoid and interdigitation zones. The match between autofluorescence imaging, indocyanine green angiography, and “en-face” OCT helped identify the acute microstructural damages in the outer retina further than the choroid. Follow-up using “en-face” EDI-OCT revealed progressive and complete recovery of the central outer retinal layers.Conclusion. “En-face” EDI SD-OCT identified the site of initial damage in MEWDS as the photoreceptors and the interdigitation layers rather than the choroid. Moreover, “en-face” OCT is helpful in the follow-up of these lesions by being able to show the recovery of the outer retinal layers.
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Banta, Fauzan Teuku, Ari Djatikusumo, Elvioza Elvioza, et al. "Pneumatic Retinopexy in Rhegmatogenous Retinal Detachment : Case Series." Ophthalmologica Indonesiana 45, no. 2 (2019): 47. http://dx.doi.org/10.35749/journal.v45i2.184.
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 In the case of rhegmatogenous retinal detachment (RRD), pneumatic retinopexy is an alternative choice besides scleral buckling and pars plana vitrectomy. This case series describes two cases of RRD with superotemporal tear treated succesfully with pneumatic retinopexy. The expandable gas used in this study was 0.4 cc perfluoropropane (C3F8) gas, patient’s head is immediately positioned face down (prone), then slowly turned into an upright position in accordance with the tear for 1-3 days. Laser retinopexy using an argon laser is performed after the retina is properly reattached. Ten months after pneumatic retinopexy, the VA of RE in case I remained at 6/18 with reattached retina. At four weeks, VA of RE in case II was at 3/60 with reattached retina. VA of both cases was relatively satisfactory with retinal reattachment in a single procedure. The anatomical and functional success of pneumatic retinopexy is related to macular status before surgery, retinal detachment area, phakic status, or the presence of PVR and high myopia. 
 
 
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Volodin, P. L., E. V. Ivanova, E. Iu Polyakova, and A. V. Fomin. "Spectral OCT-Angiography in En Face Mode for Detection of Morphological Changes in the Retinal Pigment Epithelium before and after Selective Micro-Pulse Laser Exposure in Patients with Central Serous Chorioretinopathy." Ophthalmology in Russia 16, no. 2 (2019): 192–201. http://dx.doi.org/10.18008/1816-5095-2019-2-192-201.
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Purpose — to study the morphological changes of the retinal pigment epithelium (RPE) by optical coherence tomography-angiography (OCT-A) in En Face mode before and after selective micropulse laser irradiation in patients with central serous chorioretinopathy (CSC), determine the correspondence between the topographic location of RPE defects and detachment on the OCT-angiogram in En Face mode and points of leakage on the FAG.Patients and methods. There were 20 patients (21 eyes) with CSC before and after laser treatment under the observation. All patients underwent high-resolution FAG and OCT-A using Angio Retina 2×2 or 3×3 mm protocol and Angio Retina HD 6×6 mm. The treatment was carried out in a selective micropulse mode with individual selection of parameters using the Navilas 577s navigation laser system (OD-OS, Germany) or the IQ 577 laser system (IRIDEX, USA).Results were evaluated at 2 weeks and 1 month after treatment. Results. In all cases, the leaking points of the subretinal fluid on FAG corresponded to the topographic location of defects and detachments of RPE detachment on OKT-A En Face. According to OCT-A En Face, the following morphological changes were revealed: in 5 cases — single defects of RPE, in 7 cases — multiple defects of RPE, in 9 cases of slit-like detachment of RPE, in 3 patients a combination of slit-like detachment and defect RPE. The sizes of RPE defects varied in the range from 21 to 159 microns, while their rounded shape prevailed. 1 month after the selective micropulse laser effect on OCT-A in the En Face mode, the defects were closed and the RPE detachments fit in all patients, which resulted in resorption of the subretinal fluid and the neurosensory retina attachment.Findings. OCT-A in En Face mode is a highly informative diagnostic method that allows noninvasive detection of morphological changes in RPE with a clear topographic localization relative to the retinal vascular network, as well as evaluating the effectiveness of selective micropulse laser treatment in patients with CSC.
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Hansraj, Saarang, and Raja Narayanan. "Retinal graft dislocation managed by repeat autologous retinal transplant for refractory macular hole." BMJ Case Reports 18, no. 1 (2025): e263187. https://doi.org/10.1136/bcr-2024-263187.
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A septuagenarian man presented with a visual acuity of hand motions and a large refractory macular hole (MH). We performed an autologous retinal transplant (ART) and covered the graft with fibrin glue without any endotamponade. The autograft was found to have dislocated from the MH when the patient was reviewed 1 week later. He was admitted for repeat ART surgery, where 1000 centistoke silicone oil was injected instead of fibrin glue and advised the patient to maintain a face-down position for 1 week. 1 month after the second surgery, the patient had a visual acuity of 20/200, N18. The graft was integrated at the MH site, with both donor sites well lasered and the retina attached.Our case suggests that a short-acting bioadhesive such as fibrin glue may not provide sufficient duration of support until adequate retino-retinal adhesion forms between the host and retinal graft.
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Ponce, Francisco A., Patrick P. Han, Robert F. Spetzler, Alexa Canady, and Iman Feiz-Erfan. "Associated arteriovenous malformation of the orbit and brain: a case of Wyburn-Mason syndrome without retinal involvement." Journal of Neurosurgery 95, no. 2 (2001): 346–49. http://dx.doi.org/10.3171/jns.2001.95.2.0346.
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✓ Wyburn-Mason syndrome is a rare condition associated with multiple cerebral arteriovenous malformations. The disease, also called retinoencephalofacial angiomatosis, includes lesions of the retina, brain, and skin. This disorder stems from a vascular dysgenesis of the embryological anterior plexus early in the gestational period when the primitive vascular mesoderm is shared by the involved structures. The timing of the insult to the embryonic tissue determines which structures are affected. Extensions of the lesions vary widely but cutaneous lesions are unusual. Among reports in the literature, only three cases appear to have manifested without retinal involvement. The authors report the fourth case of Wyburn-Mason syndrome in which there was no retinal involvement and the first to involve neither the retina nor the face.
Dissertations / Theses on the topic "Retina face"
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Velthoven, Mirjam Emma Johanna van. "Combined en-face optical coherence tomography and confocal ophthalmoscopy for retinal imaging." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2006. http://dare.uva.nl/document/34981.
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Hojo, Masato. "Glial cell fate specification modulated by the bHLH gene Hes5 in mouse retina." Kyoto University, 2003. http://hdl.handle.net/2433/148667.
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Onorati, Marco. "Molecular determinants of Xotx2 and Xotx5b action in retinal cell fate specification." Doctoral thesis, Scuola Normale Superiore, 2007. http://hdl.handle.net/11384/85987.
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Ellis, Gavin I. "ON T CELL FATE DECISIONS: RETINOL, METABOLISM AND ITREG DIFFERENTIATION." UKnowledge, 2013. http://uknowledge.uky.edu/microbio_etds/9.
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The mammalian immune system is equipped to both eliminate pathogenic microorganisms and tumors, while remaining in homeostasis with commensal species at mucosal surfaces and tolerant towards self. Suppressor regulatory T cells (Tregs) are a major sentinel of this immunological tolerance. Induced Tregs (iTregs) arise in the periphery following the integration of cues from the metabolites, cytokines, etc. which make up its milieu. Dysregulation of iTreg development, function or homing underlies the etiology of many autoimmune diseases and immunopathologies. The amelioration or prevention of multiple murine disease models by boosting Treg cell numbers foreshadows clinical efficacy of iTreg therapy, but an incomplete understanding of Treg development has thus far prevented successful translation. Therefore, we considered the basic biology of T cell fate decision making from two unique, but integrated angles. First, we show that the stimulation of PPARγ in human T cells upregulates RDH10, a molecule which catalyzes the rate limiting step in the oxidation of retinol to transcriptionally active all-trans retinoic acid (ATRA), a positive regulator of iTreg development. This functionally intact pathway endows T cells the ability to autonomously sense and respond to retinoid signals present during Treg development and at tissue sites. Next, we asked questions about how T cells sense nutrient and oxygen availability as they differentiate. Tregs lacking the serine/threonine kinase PINK1 have limited activation-induced phosphorylation of Akt and oxidative phosphorylation rates, and reduced suppressor function. Notably, the uncoupling of iTreg function from normal FoxP3 expression reinforces the recent hypothesis that the PI3K/Akt/mTORC1 axis and metabolic checkpoints are decisive players in the acquisition of suppressor activity. Ultimately, the studies described herein converge on Akt and metabolism, and contribute to our understanding of how T cells integrate diverse signals present during fate determinism, provoking future Treg based therapeutics.
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Vu, Ngoc-Son. "Contributions à la reconnaissance de visages à partir d'une seule image et dans un contexte non-contrôlé." Phd thesis, Grenoble INPG, 2010. https://theses.hal.science/tel-00574547v1.
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Bien qu'ayant suscité des recherches depuis 30 ans, le problème de la reconnaissance de visages en contexte de vidéosurveillance, sachant qu'une seule image par individu est disponible pour l'enrôlement, n'est pas encore résolu. Dans ce contexte, les deux défis les plus difficiles à relever consistent à développer des algorithmes robustes aux variations d'illumination et aux variations de pose. De plus, il y a aussi une contrainte forte sur la complexité en temps et en occupation mémoire des algorithmes à mettre en oeuvre dans de tels systèmes. Le travail développé dans cette thèse apporte plusieurs avancées innovantes dans ce contexte de reconnaissance faciale en vidéosurveillance. Premièrement, une méthode de normalisation des variations d'illumination visant à simuler les performances de la rétine est proposée en tant que pré-traitement des images faciales. Deuxièmement, nous proposons un nouveau descripteur appelé POEM (Patterns of Oriented Edge Magnitudes) destiné à représenter les structures locales d'une image. Ce descripteur est discriminant, robuste aux variations extérieures (variations de pose, d'illumination, d'expression, d'âge que l'on rencontre souvent avec les visages). Troisièmement, un modèle statistique de reconnaissance de visages en conditions de pose variables, centré sur une modélisation de la manière dont l'apparence du visage évolue lorsque le point de vue varie, est proposé. Enfin, une nouvelle approche visant à modéliser les relations spatiales entre les composantes du visage est présentée. A l'exception de la dernière approche, tous les algorithmes proposés sont très rapides à calculer et sont donc adaptés à la contrainte de traitement temps réel des systèmes de vidéosurveillance<br>Although having been an active research topic for 30 years, recognizing a person from surveillance having seen only one image is unsolved. Within this context, the two greatest challenges are the variations of pose and illumination. Moreover, there are strict constraints upon the complexity in both terms of computational time and stockage requirements. The work developed throughout this dissertation gives several advantages in the context of real-time and unconstrained face recognition. Firstly, an illumination normalization method simulating the performance of human retina is proposed as preprocessing algorithm. Secondly, we propose novel features called POEM (Patterns of Oriented Edge Magnitudes) for representing a local image structure. This descriptor is discriminative and robust to exterior variations (variations of pose, illumination, expression and pose that we always see when dealing with face images). Thirdly, a statistical model for robust face recognition across poses, entered on modeling how facial patch appearance changes as the viewpoint varies, is proposed. Finally, a novel approach modeling the spatial relationships between face components is developed. Except the last algorithm, all proposed methods are very fast and are therefore suitable for the constraints upon real-time of surveillance applications
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Wang, Julie Chih-Chun. "The role of intrinsic combinatorial coding by homeodomain and bHLH transcription factors in retinal cell fate specification." Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613692.
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Boije, Henrik. "Generation of Retinal Neurons : Focus on the Proliferation and Differentiation of the Horizontal Cells and their Subtypes." Doctoral thesis, Uppsala universitet, Medicinsk utvecklingsbiologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-150886.
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We have used the chicken retina as a model for investigating cell cycle regulation and cell fate commitment during central nervous system development. This thesis focuses on the characterization of and commitment to the horizontal cell fate in the retina. Horizontal cells are interneurons that provide intraretinal signal processing prior to information relay to the brain. We have identified molecular markers that selectively distinguish the three subtypes of horizontal cells, previously described in the chicken retina based on morphology. Subtype specific birth-dating revealed that horizontal cell subtypes are generated consecutively by biased progenitors that are sensitive to the inhibitory effects of follistatin. Follistatin stimulates proliferation in progenitors by repressing the differentiation signal of activin. Initially, injection of follistatin led to a decrease in committed horizontal cells but as the inhibitory effect dissipated it resulted in an increased number of horizontal cells. During development committed horizontal cell progenitors migrate to the vitreal side of the retina where they become arrested in G2-phase for approximately two days. When the arrest is overcome the horizontal cell progenitors undergo ectopic mitosis followed by migration to their designated layer. The G2-phase arrest is not triggered or maintained by any of the classic G2-arrest pathways such as DNA damage or stress. Nevertheless, we show that the cyclin B1-Cdk1 complex has a central role in maintaining this G2-phase arrest. Two transcription factors, FoxN4 and Ptf1a, are required for the generation of horizontal cells. We show that these factors are also sufficient to promote horizontal cell fate. Overexpression of FoxN4 and Ptf1a resulted in an overproduction of horizontal- and amacrine cells at the expense of ganglion- and photoreceptor cells. We identified Atoh7, a transcription factor required for the generation of ganglion cells, as a Ptf1a transcriptional target for downregulation. Our data support a common horizontal/amacrine lineage separated from the ganglion/photoreceptor lineage by the action of Ptf1a. In conclusion, these data describe several novel characteristics of horizontal cells enhancing our understanding of neural development and cell fate commitment.
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Boutzen, Jocelyn. "Contribution à la modélisation d’interface biologique par spectroscopie d’impédance : application au suivi de l’épithélium pigmenté de la rétine durant sa croissance et face à diverses perturbations." Thesis, Paris Est, 2019. http://www.theses.fr/2019PESC2044.
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Cette thèse porte sur l’étude de l’interface entre électrodes et cellules épithéliales de la rétine : l’épithélium pigmenté. Les cellules RPE (Retinal Pigment Epithelium) qui le constitue forment une monocouche qui à confluence est constituée de cellules de forme polygonale. Elles sont juxtaposées et en contact intime les unes avec les autres par la présence de jonctions serrées. Un épithélium pigmenté endommagé est souvent associé à des pathologies de la vision. La spectroscopie d’impédance est une méthode de mesure qui permet d’étudier de manière non destructive un milieu composé d’éléments diélectriques et conducteurs. Cette mesure s’applique particulièrement bien aux cellules épithéliales. On applique ceci à l’étude du tapis cellulaires. Les membranes cellulaires remplissent le rôle de milieu diélectrique alors que les milieux ioniques intra et extracellulaires peuvent être considérés conducteurs. On peut en première approche analyser le module de l’impédance mesurée à une fréquence donnée afin de suivre le développement des tissus. Par exemple dans le domaine des implants à électrodes les fréquences autour de 1 KHz sont couramment citées. On peut par la suite mesurer l’impédance dans une gamme de fréquence plus importante et appliquer un modèle composé de dipôles électriques aux mesures. L’analyse des paramètres extraits peut donner une interprétation plus fine de l’état du tapis cellulaire. Deux notions seront principalement abordées dans cette thèse. Tout d’abord l’étude de l’utilisation de l’élément à constante de phase (CPE) dans la représentation du tapis cellulaire. Ensuite dans le cadre de ce modèle on va étudier le tapis cellulaire face à différentes perturbations<br>This manuscript focuses on studying the interface between an electrode and epithelial cells of the retina: the Retinal Pigment Epithelium (RPE). The cells that are part of this epithelium develops until they form a monolayer of juxtaposed cells with close lateral contact involving the presence of tight junctions. A damaged epithelium is often associated with sight alterations.Impedance spectroscopy is a measurement method that allows to study materials containing both conducting and dielectric elements in a non–destructive way. We apply this technique to the RPE cells layer. Cells membranes are the dielectric part while the intra and extracellular mediums are the conductive parts of this material. In a first stage one can measure the impedance at a fixed frequency as a way to follow tissues development. As an example, the 1 KHz frequency is often considered in characterizing electrodes from implanted devices. One can also measure the impedance over a wider bandwidth and apply an electric model circuit to the data. The extracted parameters can give a better interpretation of the state of the cell layer. In this work, two part will be mainly investigated. First we will evaluate the use of a constant phase element in part of the electrical model describing the cell layer. Second, and considering the same model, we will observe the reaction of the model when the cells are subject to various perturbations
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Vieira, Milena Morais. "Retinol, proteÃnas transportadoras, carotenÃides, proteÃnas de fase aguda e barreira funcional intestinal em crianÃas de uma comunidade urbana de Fortaleza." Universidade Federal do CearÃ, 2007. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=1596.
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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico<br>A deficiÃncia de vitamina A (DVA) à considerada um importante problema de saÃde pÃblica em todo o mundo e o papel da DVA na integridade epitelial intestinal ainda nÃo està bem compreendido. O objetivo do trabalho foi investigar a associaÃÃo do retinol (vitamina A) e carotenÃides com a barreira funcional intestinal em crianÃas de uma comunidade urbana em Fortaleza, no Nordeste do Brasil. Participaram do estudo 102 crianÃas de 2 meses a 9 anos de idade. O estado nutricional das crianÃas foi avaliado atravÃs do escore âzâ de peso por altura (WHZ), mostrando que 19,6% (20/102) das crianÃas apresentaram desnutriÃÃo leve (âzâ escore de -1 a -2). Todas as crianÃas tiveram as concentraÃÃes de retinol determinadas e nenhuma estava severamente deficiente (< 0,35 ÂM); 2,9% (3/102) das crianÃas apresentaram nÃveis moderados de deficiÃncia de vitamina A (0,36 - 0,70 ÂM); 20,6% (21/102) apresentaram leve deficiÃncia (0,71 - 1,05 ÂM) e 76,5% (78/102) apresentaram concentraÃÃes suficientes de retinol no sangue (> 1,05 ÂM). A razÃo de lactulose/manitol (L/M) estava anormal em 49% (47/97) das crianÃas quando comparadas com crianÃas saudÃveis de uma mesma regiÃo geogrÃfica. Os carotenÃides, luteÃna, β-criptoxantina e beta-caroteno no soro das crianÃas do Parque UniversitÃrio, apresentaram correlaÃÃes inversas significativas com a razÃo de L/M. As proteÃnas de fase aguda (proteÃna C reativa, CRP e glicoproteÃna α1-Ãcida, AGP) apresentaram correlaÃÃes inversas com retinol. O retinol correlacionou-se significativamente com a proteÃna ligadora de retinol (RBP) e com a transtiretina (TTR). Esses dados sugerem que a alteraÃÃo na barreira funcional intestinal provavelmente ocorreu atravÃs do caminho paracelular com baixas concentraÃÃes de carotenÃides no soro. Os carotenÃides, precursores do retinol, poderiam assim promover um melhor marcador para a barreira funcional intestinal alterada do que as medidas de RBP ou retinol. As concentraÃÃes sanguÃneas de retinol correlacionaram-se com a RBP e TTR e correlacionaram-se inversamente com a AGP e com a CPR<br>Vitamin A deficiency (VAD) is considered an important public health problem worldwide and the role of VAD on intestinal epithelial integrity is not well understood. To investigate the association of retinol (vitamin A) and carotenoids with the intestinal barrier function from children in an urban community in Fortaleza, Northeastern Brazil, one hundred and two children from 2 months to 9 years old participated in the study. The nutritional status of these children, measured by weight for height z-score (WHZ), showed that 19.6% (20/102) of them had mild malnutrition (-1 to â2 z-score). All children had their serum retinol concentration measured and none were severely deficient (<= 0.35 ÂM), 2.9% (3/102) were moderately (0.36 â 0.70 ÂM), 20.6% (21/102) were mildly (0.71 â 1.05 ÂM) deficiencies; 76.5% (78/102) were vitamin A sufficient (> 1.05 ÂM). The lactulose:mannitol (L/M) ratio was abnormal in 49% (47/97) of children when compared to healthy children in the same geographic area. Serum carotenoids, lutein, beta-cryptoxanthin and beta-carotene showed significant inverse correlation with the L/M ratio. Acute phase proteins (C-reactive protein; CRP; and α-acid glycoprotein; AGP) were significantly inversely correlated with retinol. Retinol was significantly correlated with retinol-binding protein (RBP), and with transthyretin (TTR). These data suggest a disruption of intestinal barrier function due to paracellular pathway with low serum concentrations of carotenoids. The retinol precursors, carotenoids, may provide a better marker for disrupted intestinal barrier function than measurements of RBP or retinol. Serum retinol concentrations correlate with RBP and TTR and inversely correlate with AGP and CRP
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Vieira, Milena Morais. "Retinol, proteínas transportadoras, carotenóides, proteínas de fase aguda e barreira funcional intestinal em crianças de uma comunidade urbana de Fortaleza." reponame:Repositório Institucional da UFC, 2007. http://www.repositorio.ufc.br/handle/riufc/3744.
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VIEIRA, Milena Morais. Retinol, proteínas transportadoras, carotenóides, proteínas de fase aguda e barreira funcional intestinal em crianças de uma comunidade urbana de Fortaleza. 2007. 175 f. Tese (Doutorado em Farmacologia) - Universidade Federal do Ceará, Fortaleza, 2007.<br>Submitted by denise santos (denise.santos@ufc.br) on 2012-09-05T11:46:58Z
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Previous issue date: 2007<br>Vitamin A deficiency (VAD) is considered an important public health problem worldwide and the role of VAD on intestinal epithelial integrity is not well understood. To investigate the association of retinol (vitamin A) and carotenoids with the intestinal barrier function from children in an urban community in Fortaleza, Northeastern Brazil, one hundred and two children from 2 months to 9 years old participated in the study. The nutritional status of these children, measured by weight for height z-score (WHZ), showed that 19.6% (20/102) of them had mild malnutrition (-1 to –2 z-score). All children had their serum retinol concentration measured and none were severely deficient (<= 0.35 µM), 2.9% (3/102) were moderately (0.36 – 0.70 µM), 20.6% (21/102) were mildly (0.71 – 1.05 µM) deficiencies; 76.5% (78/102) were vitamin A sufficient (> 1.05 µM). The lactulose:mannitol (L/M) ratio was abnormal in 49% (47/97) of children when compared to healthy children in the same geographic area. Serum carotenoids, lutein, beta-cryptoxanthin and beta-carotene showed significant inverse correlation with the L/M ratio. Acute phase proteins (C-reactive protein; CRP; and α-acid glycoprotein; AGP) were significantly inversely correlated with retinol. Retinol was significantly correlated with retinol-binding protein (RBP), and with transthyretin (TTR). These data suggest a disruption of intestinal barrier function due to paracellular pathway with low serum concentrations of carotenoids. The retinol precursors, carotenoids, may provide a better marker for disrupted intestinal barrier function than measurements of RBP or retinol. Serum retinol concentrations correlate with RBP and TTR and inversely correlate with AGP and CRP<br>A deficiência de vitamina A (DVA) é considerada um importante problema de saúde pública em todo o mundo e o papel da DVA na integridade epitelial intestinal ainda não está bem compreendido. O objetivo do trabalho foi investigar a associação do retinol (vitamina A) e carotenóides com a barreira funcional intestinal em crianças de uma comunidade urbana em Fortaleza, no Nordeste do Brasil. Participaram do estudo 102 crianças de 2 meses a 9 anos de idade. O estado nutricional das crianças foi avaliado através do escore “z” de peso por altura (WHZ), mostrando que 19,6% (20/102) das crianças apresentaram desnutrição leve (“z” escore de -1 a -2). Todas as crianças tiveram as concentrações de retinol determinadas e nenhuma estava severamente deficiente (< 0,35 µM); 2,9% (3/102) das crianças apresentaram níveis moderados de deficiência de vitamina A (0,36 - 0,70 µM); 20,6% (21/102) apresentaram leve deficiência (0,71 - 1,05 µM) e 76,5% (78/102) apresentaram concentrações suficientes de retinol no sangue (> 1,05 µM). A razão de lactulose/manitol (L/M) estava anormal em 49% (47/97) das crianças quando comparadas com crianças saudáveis de uma mesma região geográfica. Os carotenóides, luteína, β-criptoxantina e beta-caroteno no soro das crianças do Parque Universitário, apresentaram correlações inversas significativas com a razão de L/M. As proteínas de fase aguda (proteína C reativa, CRP e glicoproteína α1-ácida, AGP) apresentaram correlações inversas com retinol. O retinol correlacionou-se significativamente com a proteína ligadora de retinol (RBP) e com a transtiretina (TTR). Esses dados sugerem que a alteração na barreira funcional intestinal provavelmente ocorreu através do caminho paracelular com baixas concentrações de carotenóides no soro. Os carotenóides, precursores do retinol, poderiam assim promover um melhor marcador para a barreira funcional intestinal alterada do que as medidas de RBP ou retinol. As concentrações sanguíneas de retinol correlacionaram-se com a RBP e TTR e correlacionaram-se inversamente com a AGP e com a CPR
Books on the topic "Retina face"
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Gulyakov, Aleksandr, Alexey Salomatin, Aleksander Malko, et al. The fate of the European Union and lessons for Russia. 2nd ed. Publishing Center RIOR, 2021. http://dx.doi.org/10.29039/01881-1.
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The monograph reveals the history of the creation of the European Union and its current situation, which is characterized by instability and lack of genuine unity. In an effort to integrate everything and everyone in a short time, European leaders and officials have overestimated their strength. Meanwhile, every European country retains its identity and is in no hurry to give it up.
 Russia and the participants of integration interstate associations should learn lessons from the fate of the European Union: not to force rapprochement, not to encroach on the state sovereignty of its members, to respect the opinion of ordinary people.
 The publication is intended for specialists in the field of European politics, European law, international relations, as well as for a wide range of readers interested in the political life of Europe.
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Moretti, Anna, and Francesco Zirpoli. Osservatorio sulla componentistica automotive italiana 2020. Fondazione Università Ca’ Foscari, 2020. http://dx.doi.org/10.30687/978-88-6969-482-0.
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Nell’anno 2020 l’Italia ha dovuto fare i conti con la crisi sanitaria ed economica determinata dalla diffusione del virus COVID-19. La straordinarietà della situazione, con l’Europa alle prese con lockdown e fermi produttivi, ha portato l’Osservatorio a far seguire alla tradizionale rilevazione avviata a fine Febbraio 2020 una seconda indagine di approfondimento mirata a raccogliere le prime reazioni delle imprese della filiera alla crisi da coronavirus. Questa edizione del volume è, quindi, particolarmente ricca di spunti in quanto collega la fotografia del 2019 alla situazione generata dalla pandemia nel 2020. Il quadro complessivo è quello di una filiera i cui risultati in termini di fatturato, produzione ed export erano già in contrazione nel 2019 e, di conseguenza, particolarmente esposta alla crisi del 2020, soprattutto per alcune categorie di imprese meno resilienti. Il superamento di questa situazione critica potrà giocarsi sulla capacità di sviluppare aggregazioni e reti per l’innovazione, con obiettivi importanti di competitività dell’intera filiera sullo scenario internazionale.
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Ammannati, Francesco, ed. Assistenza e solidarietà in Europa Secc. XIII-XVIII / Social assistance and solidarity in Europe from the 13th to the 18th Centuries. Firenze University Press, 2013. http://dx.doi.org/10.36253/978-88-6655-367-0.
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Il periodo compreso fra Medioevo ed Età Moderna registra una significativa evoluzione del welfare, attraverso il consolidamento e la specializzazione di istituzioni nate o trasformatesi con la precisa funzione di fare attività di solidarietà e assistenza. È attorno a queste istituzioni che si sono concentrate le ricerche raccolte in questo volume, con l’obiettivo di delinearne la nascita e l’evoluzione, ma anche le fonti di finanziamento e autofinanziamento, le strategie e le modalità di acquisizione delle risorse, la gestione e la evoluzione dei patrimoni, l’organizzazione funzionale e i costi interni di sostegno ai bisognosi e di gestione del personale. Quelle istituzioni giocarono spesso un ruolo significativo nel territorio in cui operavano e numerosi contributi si soffermano sugli effetti economici e sociali prodotti dalla loro azione, non solo in termini di redistribuzione del reddito e mantenimento della pace sociale, ma anche in relazione all’eventuale rapporto con la realtà produttiva, grazie all’immissione sul mercato di prodotti e servizi svolti dagli assistititi o dal personale dell’istituzione. Un’ultima sezione è infine dedicata alle reti di assistenza non formali (solidarietà e forme di credito in seno alle famiglie, ai gruppi di indigenti, alle comunità), attraverso le quali gli individui, le comunità e l’intera società, in assenza o carenza di strutture formalizzate, tentarono di proteggersi dai rischi legati all’indigenza e alla incapacità fisica.
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of, American Academy. Face-Down Recovery after Retinal Surgery. American Academy of Ophthalmology, 2014.
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Ueda, Sayako, and Akiyoshi Kitaoka. The Wobbling Face Illusion. Oxford University Press, 2017. http://dx.doi.org/10.1093/acprof:oso/9780199794607.003.0093.
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This chapter introduces a novel type of illusion produced by duplicating facial parts, called the Wobbling Face illusion, which causes an unstable feeling for many observers. Four experiments intended to characterize the illusion are examined. In Experiments 1 and 2, the results indicated that the Wobbling Face illusion should be specific to the face, and the unstable feeling may arise from rivalry of perception between doubled facial features. Experiment 3 showed that this illusion was the strongest when eyes were duplicated. Experiment 4 suggested that the unstable perception of this illusion did not reflect retinal slips or eye movement instabilities. Thus this face-specific illusion is not a simple motion illusion but might be based on attention instability.
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Kitchen, Clyde K. Fact and Fiction of Healthy Vision. Praeger, 2007. http://dx.doi.org/10.5040/9798400649455.
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Written by a practicing ophthalmologist, this book explains the eye and how it develops and functions—or can malfunction, especially as we age—and what our options are to maximize or retain eye health. Dr. Kitchen also explains the many treatments and surgical options available, as well as myths and false beliefs or promises that are common in relation to eye health and treatments today. Dr. Kitchen describes time-tested, proven techniques, as well as new treatments and surgeries changing the nature of eye care, including refractive surgery options. He also explains common problems from red eye to macular degeneration, and spotlights beliefs and treatment claims that are uninformed or downright deceptive. His goal is to help Boomers and parents make well-informed decisions about eye care for themselves and their family members, and also to help aging consumers retain their visual health. Appendices include a glossary of eye and eye care terms. The topics addressed include eye anatomy, examinations, medications, treatments, and surgery. Conditions described range from dry eye to ocular migraines, lazy eye, cataracts, glaucoma, and eye cancer.
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Costello, Sarah, and Kayla Kaszyca. Sounds Fake But Okay. Jessica Kingsley Publishers, 2023. http://dx.doi.org/10.5040/9781805016496.
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‘Somehow, over time, we forgot that the rituals behind dating and sex were constructs made up by human beings and eventually, they became hard and fast rules that society imposed on us all.’ True Love. Third Wheels. Dick pics. ‘Dying alone’. Who decided this was normal? Sarah and Kayla invite you to put on your purple aspec glasses - and rethink everything you thought you knew about society, friendship, sex, romance and more. Drawing on their personal stories, and those of aspec friends all over the world, prepare to explore your microlabels, investigate different models of partnership, delve into the intersection of gender norms and compulsory sexuality and reconsider the meaning of sex - when allosexual attraction is out of the equation. Spanning the whole range of relationships we have in our lives - to family, friends, lovers, society, our gender, and ourselves, this book asks you to let your imagination roam, and think again what human connection really is. Includes exclusive ‘Sounds Fake But Okay’ podcast episodes.
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Gastil, John. Designing Public Deliberation at the Intersection of Science and Public Policy. Edited by Kathleen Hall Jamieson, Dan M. Kahan, and Dietram A. Scheufele. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780190497620.013.26.
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An increasingly popular means of engaging the public uses small-scale deliberative forums, with anywhere from a dozen to hundreds or thousands of citizens meeting face-to-face or online to consider policy questions with important scientific dimensions. When designing such processes, policymakers and civic organizations need to consider how they recruit and retain engaged participants, how they structure the deliberative process itself, and the impacts they hope to achieve, not just for participants but also for the wider society. Although research conducted on deliberation shows the efficacy of these processes, the field will benefit from more systematic analysis of alternative deliberative methods, particularly at different points of entry within the policymaking system.
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Diffie, Whitfield, and Susan Landau. Privacy on the Line. The MIT Press, 1998. http://dx.doi.org/10.7551/mitpress/5571.001.0001.
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A guide to the debate over cryptography policy and the implications for individual privacy. Telecommunication has never been perfectly secure, as a Cold War culture of wiretaps and international spying taught us. Yet many of us still take our privacy for granted, even as we become more reliant than ever on telephones, computer networks, and electronic transactions of all kinds. Whitfield Diffie and Susan Landau argue that if we are to retain the privacy that characterized face-to-face relationships in the past, we must build the means of protecting that privacy into our communication systems. Diffie and Landau strip away the hype surrounding the policy debate to examine the national security, law enforcement, commercial, and civil liberties issues. They discuss the social function of privacy, how it underlies a democratic society, and what happens when it is lost.
Book chapters on the topic "Retina face"
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Cheng, Yong, YingKun Hou, and Zuoyong Li. "An Improved Retina Modeling for Varying Lighting Face Recognition." In Advances in Intelligent and Soft Computing. Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-25664-6_66.
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Khatib, Nora, and Robert E. Coffee. "Vascular Malformations of the Retina and Posterior Segment of the Eye." In Vascular Lesions of the Orbit and Face. Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-29704-0_3.
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Lumbroso, Bruno, Marco Rispoli, Jean Francois Le Rouic, and Maria Cristina Savastano. "En Face' Optical Coherence Tomography Scan Applications in the Inner Retina." In Optical Coherence Tomography. S. KARGER AG, 2014. http://dx.doi.org/10.1159/000356397.
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Huq, Mahmudul, Javier Garrigos, Jose Javier Martinez, JoseManuel Ferrandez, and Eduardo Fernández. "Application of RESNET and Combined RESNET+LSTM Network for Retina Inspired Emotional Face Recognition System." In Artificial Intelligence in Neuroscience: Affective Analysis and Health Applications. Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-06242-1_63.
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Garanto, Alejandro. "Delivery of Antisense Oligonucleotides to the Mouse Retina." In Methods in Molecular Biology. Springer US, 2022. http://dx.doi.org/10.1007/978-1-0716-2010-6_22.
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AbstractThe eye is the organ in charge of vision and, given its properties, has become an excellent organ to test genetic therapies, including antisense oligonucleotide (AON) technology. In fact, the first AON receiving FDA and EMA approval was meant to treat an eye condition. Currently, dozens of clinical trials are being conducted for a variety of subtypes of inherited retinal disease. Although most of them are based on gene augmentation therapies, a phase 3 and two phase 1/2 clinical trials using AONs are ongoing. Since the retina is a layered structure of nondividing cells, obtaining human retinal tissue and expanding it in the lab is not possible, unless induced pluripotent stem cell technology is used. Mouse models have helped to elucidate the function of many genes, and the retinal structure is quite similar to that of humans. Thus, drug delivery to the mouse eye can provide valuable information for further optimization of therapies. In this chapter, the protocol for intravitreal injections of AONs is described in detail.
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Moody, Sally A. "Testing Retina Fate Commitment in Xenopus by Blastomere Deletion, Transplantation, and Explant Culture." In Retinal Development. Humana Press, 2012. http://dx.doi.org/10.1007/978-1-61779-848-1_7.
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Ma, Wenxin, and Shu-Zhen Wang. "Fate Tracing of neurogenin2-Expressing Cells in the Mouse Retina Using CreER™: LacZ." In Retinal Development. Humana Press, 2012. http://dx.doi.org/10.1007/978-1-61779-848-1_9.
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Kumar, Justin P., and Kevin Moses. "Cell Fate Specification in the Drosophila Retina." In Results and Problems in Cell Differentiation. Springer Berlin Heidelberg, 2000. http://dx.doi.org/10.1007/978-3-540-46826-4_6.
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Austin, C. P., and C. L. Cepko. "Specification of Cell Fate in the Vertebrate Retina." In Neural Cell Specification. Springer US, 1995. http://dx.doi.org/10.1007/978-1-4615-1929-4_11.
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Rollend, Derek, Paul Rosendall, Seth Billings, Philippe Burlina, Kevin Wolfe, and Kapil Katyal. "Face Detection and Object Recognition for a Retinal Prosthesis." In Computer Vision – ACCV 2016 Workshops. Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-54407-6_20.
Full textConference papers on the topic "Retina face"
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Fischer, Yann, Olivier Martinache, Zofia Bratasz, Marius Dubosc, and Michael Atlan. "Retinal blood flow estimation by digital holography: Mitigating the effect of illumination power variations." In Digital Holography and Three-Dimensional Imaging. Optica Publishing Group, 2024. http://dx.doi.org/10.1364/dh.2024.th2a.4.
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High-speed digital holography unveils local blood flow contrasts in the eye fundus through deterministic signal analysis using a forward scattering model of dynamically diffused light, enabling estimation of absolute blood flow in primary in-plane retinal arteries. However, total retinal blood volume estimation faces low reproducibility due to laser illumination power variations. Intra-individual reproducibility is improved by renormalizing based on the assessment of illumination power from the modulation depth of interferograms.
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Jones, Chris, Stephanie Edmunds, Kevin Janak, and Jean Molina. "Sustainable Biocide Formulations to Deliver Controlled Post Fracture Souring Management." In CORROSION 2017. NACE International, 2017. https://doi.org/10.5006/c2017-09115.
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Abstract Hydraulic fracturing, used in unconventional shale gas and oil extraction, uses large amounts of water which needs to be treated with biocides to prevent microbial degradation of the fracturing fluids and subsequent microbial contamination of the reservoir. A growing requirement is to deliver an holistic biocide package that can provide protection ‘on-the-fly' and post fracturing in the reservoir where the newly opened fracture faces, introduction of nutrients and degradable carbon sources provide a favorable environment for microbial growth. Many commonly used fracturing biocides are inactive in the reservoir and therefore biocide chemistries that can retain their activity, have good tolerance to temperature and are not inactivated by hydrogen sulfide may be used. Experimental work has demonstrated that novel combinations of the preservative 1,3-Dimethylol-5,5- dimethylhydantoin and tetrakis hydroxymethyl phosphonium sulfate (THPS).can provide synergistic biocidal performance against commonly found oilfield bacteria. Whilst 1,3-Dimethylol-5,5- dimethylhydantoin can be considered a functional equivalent to biocides such as dimethyl oxazolidine, its controlled release profile appears to supplement and enhance the performance of THPS when either co-applied or co-formulated and results observed over an extended time period.
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Colwell, Richard L., and William Layo. "Flux-Core Welding in Refinery Service." In CORROSION 2008. NACE International, 2008. https://doi.org/10.5006/c2008-08553.
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Abstract While its reputation has been stigmatized by early quality problems in the 1980’s, Flux-Core Arc Welding (FCAW) has evolved into a process by which experienced fabricators can obtain radiographic quality welds in many alloy systems. Research and development, modem manufacturing techniques, and improvement in sensor and inspection technologies have produced consumables for gas-shielded procedures that can meet many petroleum refinery industry specifications. During the last decade there has been increased pressure exerted by fabricators on buyers to utilize Flux-Core Arc Welding (FCAW) where possible. In spite of the fact that there is reluctance on the part of process industry to accept the FCAW process, today’s competitive market has enabled fabricators to persuade segments of the power, chemical, and petroleum processing industry to accept FCAW for pressure vessel, heat exchanger, and piping fabrication applications in order to reduce both cost and schedule. Even though many refinery owner/operators' specifications prohibit the use of FCAW for radiograph quality welds, there has been a growing trend to rethink the restriction, and allow the controlled use of FCAW (gas shielded) for petroleum refinery pressure retaining welds. This paper discusses the author's experiences with the increasing use and ongoing limitations of FCAW(G).
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Ngoc-Son Vu and Alice Caplier. "Illumination-robust face recognition using retina modeling." In 2009 16th IEEE International Conference on Image Processing ICIP 2009. IEEE, 2009. http://dx.doi.org/10.1109/icip.2009.5413963.
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Borycki, Dawid, Marta Mikuła-Zdańkowska, Piotr Węgrzyn, and Maciej Wojtkowski. "Computational aberration correction enables full-thickness, neuronal-level human retinal imaging with spatio-temporal optical coherence tomography (STOC-T)." In Optical Coherence Tomography. Optica Publishing Group, 2024. http://dx.doi.org/10.1364/oct.2024.cm5e.3.
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We demonstrate that spatio-temporal optical coherence tomography (STOC-T) supported by computational aberration correction provides neuronal-level imaging of the human retina. We show en face images depicting the amacrine cells, the multipolar retinal neurons.
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Cheong, Yuen Kiat, Vooi Voon Yap, and Humaira Nisar. "A robust face recognition algorithm under varying illumination using adaptive retina modeling." In 2013 INTERNATIONAL SYMPOSIUM ON COMPUTATIONAL MODELS FOR LIFE SCIENCES. AIP, 2013. http://dx.doi.org/10.1063/1.4825007.
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Rosen, Richard B., Adrian G. Podoleanu, John A. Rogers, et al. "Challenges and recognizable patterns in the en-face OCT of the retina." In Biomedical Optics 2004, edited by Valery V. Tuchin, Joseph A. Izatt, and James G. Fujimoto. SPIE, 2004. http://dx.doi.org/10.1117/12.531334.
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Holmes, T., S. Larkin, M. Downing, and K. Csaky. "En-face imaging of the ellipsoid zone in the retina from optical coherence tomography B-scans." In SPIE BiOS, edited by Fabrice Manns, Per G. Söderberg, and Arthur Ho. SPIE, 2015. http://dx.doi.org/10.1117/12.2074193.
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Podoleanu, Adrian Gh, George M. Dobre, David J. Webb, and David A. Jackson. "En-face OCT imaging of the retina using path modulation introduced by the transversal scanning mirror." In Advances in Optical Imaging and Photon Migration. OSA, 1998. http://dx.doi.org/10.1364/aoipm.1998.amc4.
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Lennie, Peter. "Retinal receptive fields and eccentricity." In OSA Annual Meeting. Optica Publishing Group, 1985. http://dx.doi.org/10.1364/oam.1985.thf1.
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In animals like cat and monkey, which have a specialized central area in the retina, the distribution of photoreceptors and the organization of their connections to the brain change greatly as one moves from the central to the peripheral retina. This is reflected in several properties of retinal ganglion cells whose axons form the optic nerve. The density of cells is highest in the central area and, despite the fact that the smallest receptive fields are found there, the overlap of receptive fields is generally greatest. Increasing eccentricity leads to reduced density of cells, larger receptive fields, and some changes in the temporal characteristics of their responses. The interpretation of these observations is made more complicated by the fact that in both species several distinct classes of ganglion cell have been identified and these differ in their distributions on the retina. The purpose of the talk is to characterize the general changes in properties of retinal ganglion cells that occur as one moves from the central to the peripheral retina and to compare the representations of the image transmitted by the different classes of cell.
Reports on the topic "Retina face"
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Johnson, Eric M., Edwin Lehoahoa, Patrick Shaw, and Rob Urquhart. Increasing Digital Platform Use to Help Youth Find Work. RTI Press, 2020. http://dx.doi.org/10.3768/rtipress.2020.pb.0023.2005.
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Young people face myriad obstacles in finding work, leaving more than 71 million unemployed globally. Digital professional networking platforms, such as LinkedIn, may give youth an effective way to find, retain, and advance in work. We explore platform use in developing economies and present new data on a low-cost, successful way to teach youth how to use these platforms. We end by drawing policy implications for the education and workforce development field.
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Lafuente, Mariano. Public Employment and Pay Policy in Belize. Inter-American Development Bank, 2013. http://dx.doi.org/10.18235/0009134.
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Due in part to Belize's characteristic as a small state, its public administration is among the most expensive in Central America relative to the size of its economy. This represents a potential risk in a challenging fiscal context. The wage bill's fiscal risk has been flagged as a concern over the years, and it has remained an important issue, which is aggravated by the fact that the relatively high level of spending still does not effectively promote, attract, and retain adequate human capital for the delivery of public services. This Technical Note reviews the current public employment and pay policy in Belize, and proposes short and medium-term measures to achieve important human resource management objectives in the public sector, including to develop a fiscally sustainable wage bill, attract and retain required human capital, and enhance performance orientation in the public sector.
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Rentería Palomares, Zaira, Jorge Gutiérrez García, and Daniel Perdomo Rodríguez. Digitalization in the Extractive Sector: A Comparative Analysis of the Andean Region. Inter-American Development Bank, 2022. http://dx.doi.org/10.18235/0004675.
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Global efforts to achieve the climate goals specified in the Paris Agreement pose major challenges for the global production system, because demand for clean fuels, metals, and minerals will increase considerably in the coming decades. This trend is the main driver for extractive companies transformations of their production systems to maintain their profitability and operability in the face of an increasingly stringent context in economic, environmental, and social terms. Hence, the adoption of digital technologies appears as a unique opportunity that would enable the industry to meet the challenges posed by the energy transition that is looming. In this challenging context, companies in the extractive sector have started to rethink not only their internal operations, but also the ways in which they interact with communities, the environment, and public opinion.
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Talamas Marcos, Miguel Ángel. Preliminary Evidence of Surviving Competition: Neighborhood Shops vs. Convenience Chains. Inter-American Development Bank, 2022. http://dx.doi.org/10.18235/0004453.
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Hundreds of millions of microenterprises in emerging economies face increased competition from the entry and expansion of large firms that offer similar products. This paper studies how one of the worlds most prevalent microenterprises, neighborhood shops, confront competition from convenience chains (e.g., 7-Eleven) in Mexico. To address the endogeneity in time and location of chains store openings, I pair two-way fixed effects with a novel instrument that, at the neighborhood level, shifts the profitability of chains but not of shops. An expansion from zero to the average number of chain stores in a neighborhood reduces the number of shops by 16%. Consistent with the theoretical framework, this reduction is not driven by an increase in shop exit but by a decrease in shop entry. Shops retain their sales of fresh products and 96% of their customers, but customers visit shops less often and spend less on non-fresh and packed goods. I present evidence consistent with shops surviving by exploiting comparative advantages stemming from being small and owner-operated, such as lower agency costs, building relationships with the community, and offering informal credit.
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Talamas Marcos, Miguel Ángel. Surviving Competition: Neighborhood Shops vs. Convenience Chains. Inter-American Development Bank, 2023. http://dx.doi.org/10.18235/0005065.
Full textAbstract:
Hundreds of millions of microenterprises in emerging economies face increased competition from the entry and expansion of large firms that offer similar products. This paper studies how one of the world's most prevalent microenterprises, neighborhood shops, confront competition from convenience chains (e.g., 7-Eleven) in Mexico. To address the endogeneity in time and location of chain store openings, I pair two-way fixed effects with a novel instrument that, at the neighborhood level, shifts the profitability of chains but not of shops. An expansion from zero to the average number of chain stores in a neighborhood reduces the number of shops by 15%. This reduction is not driven by increased shop exits but by decreased shop entries. Shops retain their sales of fresh products and 96% of their customers, but customers visit shops less often and spend less on non-fresh and packed goods. The evidence suggests that shops survive by exploiting comparative advantages stemming from being small and owner-operated, such as lower agency costs, relationships with the community, broader and tailored product mix, and informal credit. The welfare gains of convenience chains replacing shops are increasing in household income.
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Godfrey, Jody. Transit Workforce Development Challenges and Mitigation Practices. Mineta Transportation Institute, 2024. http://dx.doi.org/10.31979/mti.2024.2361.
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The objective of this research is to summarize previously conducted research related to workforce development challenges in the transit industry, detailing major findings and subsequent recommendations based on the annotated bibliography of the current atmosphere and most successful ways to mitigate those challenges to attract and retain talent in the transit industry. According to the U.S. Chamber of Commerce, the U.S. had over 10 million job openings and only 5.7 million unemployed workers in March 2023. In 2017, the Washington Post posited that there were not enough workers to fill the vacancies, as the U.S. Census Bureau announced a 17-year low in unemployment while the Bureau of Labor Statistics hit record streaks for numbers of job openings. The COVID-19 pandemic exacerbated the employment challenges that the U.S. already faced. To top it all, the pandemic also led to increased retirement rates among those close to retirement age. This provides transit industry executives and transportation professionals, with ideas of tools that are available to help attract more qualified candidates to the transit industry and ways to advance the development of the transit workforce. This research highlights some of the social media recruiting; online hiring platform improvements; and partnerships with career centers, universities, and recruitment centers to attract new employees to the transit workforce. In addition, increases in pay, benefits, bonuses, providing flexible schedule options and some other atypical ideas have successfully been used to retain workers in the transit workforce. This research focuses on ways in which all transit stakeholders can invest in all aspects of industry workforce development to ensure qualified employees choose the transit industry and that they are subsequently trained to be the most beneficial assets to the organization and remain there via effective retention strategies.
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Krylova-Grek, Yulia, and Mariya Shyshkina. Blended Learning Method for Improving Students' Media Literacy Level. [б. в.], 2020. http://dx.doi.org/10.31812/123456789/4467.
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The paper discusses the issues of improving students' media literacy skills to help them to navigate through an increasingly complex information so- ciety. It reports on a project aimed at applying the blended learning model to boost high school students' media literacy levels. The given model is recognized to have a number of advantages for both teachers (tutors) and learners (students). It is generally accepted that the blended learning method provides students with profound theoretical knowledge and retains the emphasis on practice. Besides, online classes offer a great opportunity to reach a wider audience. The purpose of the paper is to describe the authors' experience in introducing a new method for improving the learners' media literacy skills based on the blended learning model. The survey responses demonstrated that the accessibility, ease-of-use, and duration of the classes were deemed effective in terms of students' engagement and increases in their media literacy level. The course helped learners to develop their critical thinking and other media-related skills, to identify propaganda, ma- nipulation, and fake messages found in media streams.
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Deza, María Cecilia, Mariana Dondo, H. Xavier Jara, David Arturo Rodríguez Guerrero, and Javier Torres. Assessing the Role of Tax-benefit Systems in Reducing the Gender Income Gap in Latin America. Inter-American Development Bank, 2025. https://doi.org/10.18235/0013356.
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This paper aims to assess the extent to which cash transfers, direct taxes, and social contributions help to reduce gender income inequalities in seven Latin American countries: Argentina, Bolivia, Colombia, Ecuador, Mexico, Peru, and Uruguay. We apply microsimulation techniques to household survey data and allocate incomes within the household, assuming that each person retains the income they receive (e.g., earnings, benefits targeting mothers) and pays taxes and social insurance contributions on an individual basis according to each countrys rules. Then, we compare gender income ratios based on market (before taxes and benefits) and disposable (after taxes and benefits) income. Our results show that, at the bottom of the distribution, tax-benefit systems significantly reduce gender income disparities in most countries due to the effect of social assistance benefits received by mothers in poor households. Additionally, we find that women have substantially higher poverty rates than men based on individual disposable income. Gender differences in poverty fade away when income is pooled at the couple level and, even more so, at the household level.
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Goswami, Partha. The Software-defined Vehicle: Its Current Trajectory and Execution Challenges. SAE International, 2024. http://dx.doi.org/10.4271/epr2024027.
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<div class="section abstract"><div class="htmlview paragraph">Original equipment manufacturers, Tier 1 suppliers, and the rest of the value chain, including the semiconductor industry, are reshaping their product portfolios, development processes, and business models to support this transformation to software-defined vehicles (SDVs). The focus on software is rippling out through the automotive sector, forcing the industry to rethink organization, leadership, processes, and future roadmaps.</div><div class="htmlview paragraph"><b>The Software-defined Vehicle: Its Current Trajectory and Execution Challenges</b> assesses the state of SDVs and explores the potential hurdles to execution and examines the work being done in the industry. The goal is to evaluate whether the implementation of SDVs will encounter the same fate as electrification or autonomous technologies, which after some level of disillusionment, are expected to pick up momentum in a more mature way.</div><div class="htmlview paragraph"><a href="https://www.sae.org/publications/edge-research-reports" target="_blank">Click here to access the full SAE EDGE</a><sup>TM</sup><a href="https://www.sae.org/publications/edge-research-reports" target="_blank"> Research Report portfolio.</a></div></div>
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Puerta, Juan Manuel, Germán Ferreyra, Alejandro Pablo Taddia, and Francesca Castellani. Development Lending for a New Reality: The Evolution of Financing Instruments across Multilateral Development Banks. Inter-American Development Bank, 2023. http://dx.doi.org/10.18235/0004762.
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Multilateral development banks (MDBs) realize their objective of promoting sustainable development through a combination of financing (lending, guarantees) and non-financing instruments (technical assistance). This technical note reviews the historical evolution and existing offering of financing instruments across MDBs. Financing instruments can be roughly grouped into seven categories: traditional investment lending, programmatic approaches, policy-based lending, emergency lending, disaster risk management instruments, results-based lending, and guarantees. Financing instruments across all MDBs are remarkably similar and they were even introduced at about the same time. The existing offering of instruments is characterized by a high level of inertia, and thus remains dominated by the first lending instrument introduced at MDBs in the 1940s: the traditional Investment Loan. In adapting to the new economic and social environment faced by borrowing member countries today, MDBs have the opportunity to rethink their lending toolkit. Investment lending could be simplified. The focus could be shifted from reviewing eligible expenses to ensuring the attainment of development results and the strengthening of national systems. Instruments that finance reforms as well as result-based instruments continue to have great potential for a renewed results focus. Finally, since the 1940s, MDBs have progressively moved from financing stand-alone infrastructure projects to financing all types of government programs over longer periods of time. Programmatic approaches that facilitate the preparation and assessment of development programs are likely to play an important role in the future.