Uv Radiation
Uv Radiation - Related Videos
09:31
Determining the Toxicity of UV Radiation and Chemicals on Primary and Immortalized Human Corneal Epithelial Cells
0 Views •
Cited by 1 •
2021
This article describes the procedures used to evaluate the toxicity of UV radiation and chemical toxins on a primary and immortalized cell line.
08:17
Dynamic Lung Tumor Tracking for Stereotactic Ablative Body Radiation Therapy
0 Views •
Cited by 9 •
2015
Stereotactic ablative body radiation therapy (SBRT) involves the precise delivery of high-dose radiation to cancer tumor targets. A novel SBRT platform offers a first-of-its-kind gimbaled radiation accelerator mounted within a pivoting O-ring gantry capable of dynamic image-guided tumor tracking. Here, we describe dynamic tumor tracking for lung targets.
02:59
Biological Effects of Radiation
0 Views •
2020
All radioactive nuclides emit high-energy particles or electromagnetic waves. When this radiation encounters living cells, it can cause heating, break chemical bonds, or ionize molecules. The most serious biological damage results when these radioactive emissions fragment or ionize molecules. For example, α and β particles emitted from nuclear decay reactions possess much higher energies than ordinary chemical bond energies. When these particles strike and penetrate matter, they produce ions...
04:55
UV-Vis Spectroscopy of Dyes - Concepts
0 Views •
2020
Absorbance When light interacts with a substance, a portion of the light is absorbed while the rest is either reflected or transmitted through it. Substances that we perceive as having a color reflect light in the visible range. The color of the substance that we are able to see depends on which wavelength of light is reflected. A substance that we perceive as blue reflects light in the blue range (430 – 480 nm) of the visible spectrum. According to the color wheel, the same substance absorbs...
05:14
Minimum Erythematous Dose Assay: A Method for Measuring UV Sensitivity in Mouse Models
0 Views •
2023
This video describes a method to measure UV sensitivity in a humanized mouse model—a mouse model that mimics human skin. We determine the minimal erythematous dose (MED) of UV radiation that can cause erythema or edema on the skin. The method can help to find out the efficacy of drugs used to reduce UV sensitivity.
FAQs
The biological effect depends on both the wavelength of the radiation and the exposure level. These factors influence how much energy cells receive and the extent of molecular injury that follows. DNA can absorb ultraviolet photons and form lesions such as pyrimidine dimers, so different exposure conditions can produce different levels of cellular damage.
Pyrimidine dimers are DNA lesions produced when ultraviolet photons are absorbed by neighboring pyrimidine bases. They provide a direct molecular link between exposure and genetic damage. Studying these lesions helps researchers examine how ultraviolet stress contributes to mutation and how effectively organisms activate DNA repair pathways to counter the injury.
Protection operates through several complementary responses rather than one single barrier. Protective pigments can limit harmful effects, antioxidant defenses can address chemically damaging reactions, and DNA repair pathways can remove or correct lesions. Behavioral responses add another level of protection by reducing exposure, helping organisms limit biological damage under changing environmental conditions.
The outcome reflects the interaction between exposure conditions and biological defenses. Wavelength and exposure level influence the initial molecular damage, while pigments, antioxidant defenses, DNA repair, and behavior influence how much of that damage persists. This balance helps explain why ultraviolet exposure can be studied in relation to mutation, aging, photosensitivity, and ecological stress.
Controlled exposure allows investigators to examine biological responses under defined ultraviolet conditions. By regulating exposure levels and wavelength, researchers can investigate molecular damage, cellular responses to environmental change, or the effectiveness of protective mechanisms. This approach also supports microbial inactivation studies, where ultraviolet treatment is used to examine how exposure affects microbial survival.
Research can connect ultraviolet exposure with several biological outcomes, including mutation, aging, photosensitivity, and ecological stress. At the cellular level, studies can focus on DNA lesions and repair responses; at broader levels, they can examine protective pigments, antioxidant defenses, and behavioral changes. Together, these perspectives show how organisms respond to environmental radiation.
Its relevance extends from molecular processes to whole-organism and ecological responses. Ultraviolet exposure can be examined through DNA lesions, cellular stress, protective mechanisms, microbial inactivation, photosensitivity, and changes associated with environmental conditions. This broad scope makes the topic useful for linking chemical reactions in cells with organismal protection and ecological stress.