![]() The year 1500 is more a cutoff date of convenience, marking the. Evolving from its original meaning, incunabulum came to mean 'place of birth' or 'beginning.' In the world of books, the word incunabula refers to books that were printed using metal type up to the year 1500. For certain cases, this is thought to allow for a greater chance of implantation success. Incunabula is the plural of the Latin word incunabulum, a cradle. In Vitro Fertilizationĭuring in vitro fertilization (IVF) procedures, a technique called assisted hatching creates a small hole in the outer shell prior to transfer. As age increases, the thickness of the membrane increases, making it harder for the embryo to break free prior to implantation. Advanced Maternal AgeĪdvanced maternal age (AMA) has an impact on the thickness of the zona pellucida. Hatchingīy the time the embryo reaches the uterus, the zona pellucida has thinned enough for the embryo to break out of the shell, or "hatch" allowing for it to make contact with the endometrium. Once fertilized, the zona pellucida prevents additional sperm from fertilizing the egg. This works to prevent unhealthy or weak sperm from reaching the egg itself. The thinning allows for penetration by the sperm, while remaining thick enough to regulate the potential sperm matches. However, as it progresses through the tube, the lining of the shell begins to thin. Many marine animals such as jellyfish are highly transparent.Once the egg is released from the ovary, it remains membrane coated as it travels through the fallopian tube. This is easier in dimly-lit or turbid seawater than in good illumination. The attenuation of light of all frequencies and wavelengths is due to the combined mechanisms of absorption and scattering.Transparency can provide almost perfect camouflage for animals able to achieve it. The frequencies of the spectrum which are not absorbed are either reflected or transmitted for our physical observation. They absorb certain portions of the visible spectrum while reflecting others. Many substances are selective in their absorption of white light frequencies. Many such substances have a chemical composition which includes what are referred to as absorption centers. Materials which do not transmit light are called opaque. Absence of structural defects (voids, cracks, etc.) and molecular structure of most liquids are mostly responsible for excellent optical transmission. Many liquids and aqueous solutions are highly transparent. Some materials, such as plate glass and clean water, transmit much of the light that falls on them and reflect little of it such materials are called optically transparent. Photons interact with an object by some combination of reflection, absorption and transmission. These interactions depend on the wavelength of the light and the nature of the material. When light encounters a material, it can interact with it in several different ways. The opposite property of translucency is opacity. Transparent materials appear clear, with the overall appearance of one color, or any combination leading up to a brilliant spectrum of every color. A transparent material is made up of components with a uniform index of refraction. In other words, a translucent material is made up of components with different indices of refraction. Translucency (also called translucence or translucidity) allows light to pass through, but does not necessarily (again, on the macroscopic scale) follow Snell's law the photons can be scattered at either of the two interfaces, or internally, where there is a change in index of refraction. On a macroscopic scale (one in which the dimensions are much larger than the wavelengths of the photons in question), the photons can be said to follow Snell's law. In the field of optics, transparency (also called pellucidity or diaphaneity) is the physical property of allowing light to pass through the material without appreciable scattering of light. Wikipedia Rate this definition: 0.0 / 0 votes
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