Show Advanced Search

REFINE YOUR SEARCH:

Containing Text
- - -
+
Filter by author or institution
GO
Filter by publication date
From:
October, 2006
Until:
Today
Filter by journal section

Filter by science education

 
 
Photoreceptor Cells: Specialized cells that detect and transduce light. They are classified into two types based on their light reception structure, the ciliary photoreceptors and the rhabdomeric photoreceptors with Microvilli. Ciliary photoreceptor cells use Opsins that activate a Phosphodiesterase phosphodiesterase cascade. Rhabdomeric photoreceptor cells use opsins that activate a Phospholipase c cascade.

Imaging Ca2+ Dynamics in Cone Photoreceptor Axon Terminals of the Mouse Retina

1Institute for Ophthalmic Research, University of Tübingen, 2Graduate School of Cellular & Molecular Neuroscience, University of Tübingen, 3Bernstein Centre for Computational Neuroscience, University of Tübingen, 4Molecular Genetics Laboratory, University of Tübingen, 5Centre for Ophthalmology, University of Tübingen

JoVE 52588


 Neuroscience

Analyzing Dendritic Morphology in Columns and Layers

1Section on Neuronal Connectivity, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), 2Mathematical and Statistical Computing Laboratory, Center for Information Technology, National Institutes of Health (NIH), 3Biomedical Imaging Research Services Section, Center for Information Technology, National Institutes of Health (NIH)

JoVE 55410


 Neuroscience

Ophthalmoscopic Examination

JoVE 10146

Source: Richard Glickman-Simon, MD, Assistant Professor, Department of Public Health and Community Medicine, Tufts University School of Medicine, MA

The simplest ophthalmoscopes consist of an aperture to look through, a diopter indicator, and a disc for selecting lenses. The ophthalmoscope is primarily used to examine the fundus, or the inner wall of the posterior eye, which consists of the choroid, retina, fovea, macula, optic disc, and retinal vessels (Figure 1). The spherical eyeball collects and focuses light on the neurosensory cells of the retina. Light is refracted as it passes sequentially through the cornea, the lens, and the vitreous body. The first landmark observed during the funduscopic exam is the optic disc, which is where the optic nerve and retinal vessels enter the back of the eye (Figure 2). The disc usually contains a central whitish physiologic cup where the vessels enter; it normally occupies less than half the diameter of the entire disc. Just lateral and slightly inferior is the fovea, a darkened circular area that demarcates the point of central vision. Around this is the macula. A blind spot approximately 15° temporal to the line of gaze results from a lack of photoreceptor cells at the optic disc.

Defined Xeno-free and Feeder-free Culture Conditions for the Generation of Human iPSC-derived Retinal Cell Models

1Institut de la Vision, Sorbonne Université, INSERM, CNRS, F-75012 Paris, France

JoVE 57795


 Developmental Biology

Ultrahigh Resolution Mouse Optical Coherence Tomography to Aid Intraocular Injection in Retinal Gene Therapy Research

1Research Service, VA Western New York Healthcare System, 2Department of Ophthalmology, (Ross Eye Institute), Jacobs School of Medicine and Biomedical Sciences, University at Buffalo- SUNY, 3Pharmacology/Toxicology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo- SUNY, 4Physiology/Biophysics, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo- SUNY, 5Neuroscience Program, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo- SUNY, 6The RNA Institute, University at Buffalo- SUNY, 7The SUNY Eye Institute

Video Coming Soon

JoVE 55894


 JoVE In-Press

Physical Properties Of Minerals I: Crystals and Cleavage

JoVE 10007

Source: Laboratory of Alan Lester - University of Colorado Boulder

The physical properties of minerals comprise various measurable and discernible attributes, including color, streak, magnetic properties, hardness, crystal growth form, and crystal cleavage. Each of these properties are mineral-specific, and they are fundamentally related to a particular mineral’s chemical make-up and atomic structure. This experiment examines two properties that stem primarily from symmetric repetition of fundamental, structural atomic groupings, called unit cells, within a crystal lattice, a crystal growth form, and crystal cleavage. Crystal growth form is the macroscopic expression of atomic-level symmetry, generated by the natural growth process of adding unit cells (the molecular building blocks of minerals) to a growing crystal lattice. Zones of rapid unit-cell-addition become the edges between the planar surfaces, i.e. faces, of the crystal. It is important to recognize that rocks are aggregates of mineral grains. Most rocks are polymineralic (multiple kinds of mineral grains) but some are effectively monomineralic (composed of a single mineral). Because rocks are combinations of minerals, rocks are not referred to as having crystal form. In some cases, geologists refer to rocks as having a general cleavage, but here the term is simply used


 Earth Science

Color Afterimages

JoVE 10194

Source: Laboratory of Jonathan Flombaum—Johns Hopkins University

Human color vision is impressive. People with normal color vision can tell apart millions of individual hues. Most amazingly, this ability is achieved with fairly simple hardware.

Part of the power of human color vision comes from a clever bit of engineering in the human brain. There, color perception relies on what is known as an 'opponent system.' This means that the presence of one kind of stimulus is treated as evidence for the absence of another, and vice versa; absence of one kind of stimulus is taken as evidence for the presence of the other. In particular, in the human brain there are cells that fire both when they receive signals to suggest that blue light is present, or when they do not receive signals suggesting yellow light. Similarly, there are cells that fire in the presence of yellow or the absence of blue. Blue and yellow are thus treated as opponent values in one dimension, and can be thought of as negative versus positive values on one axis of a Cartesian plane. If a stimulus is characterized as having a negative value on that axis, it can't also have a positive value. So, if it is characterized as yellow, it can't also be characterized as blue. Similarly, green and red (or really, magenta), o


 Sensation and Perception

Measurement of Energy Metabolism in Explanted Retinal Tissue Using Extracellular Flux Analysis

1Division of Metabolism, Endocrinology and Lipid Research, Department of Medicine, Washington University School of Medicine, 2Department of Biomedical Engineering, Washington University in Saint Louis, 3Department of Ophthalmology and Visual Science, Washington University School of Medicine

Video Coming Soon

JoVE 58626


 JoVE In-Press

Engineering Transplantation-suitable Retinal Pigment Epithelium Tissue Derived from Human Embryonic Stem Cells

1U861, I-Stem, Association Française contre les Myopathies (AFM), Institut National de la Santé et de la Recherche Médicale (INSERM), 2U861, I-Stem, Association Française contre les Myopathies (AFM), Université Evry Val-d'Essonne (UEVE), 3I-Stem, Association Française contre les Myopathies (AFM), Centre pour L’Etude des Cellules Souches (CECS), 4Banque de tissus humain, Hôpital Saint Louis, Assistance Publique - Hôpitaux de Paris (AP-HP), 5Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012

JoVE 58216


 Developmental Biology

Regenerative Therapy by Suprachoroidal Cell Autograft in Dry Age-related Macular Degeneration: Preliminary In Vivo Report

1Low Vision Research Centre of Milan, 2Department of Ophthalmology, A. Fiorini Hospital, Sapienza University of Rome, 3Glaucoma and Low Vision Study Center, Department of General Surgery and Organ Transplants, University of Bologna, 4Department of Sense Organs, Faculty of Medicine and Odontology, Sapienza University of Rome

JoVE 56469


 Medicine

123
More Results...