Ultraviolet radiation (UV)

Июль 29, 2022

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Ultraviolet radiation (UV)

Содержание

2. Research questions: 1.What is ultraviolet? 2. What are its mechanisms? 3. How does it influence flora
4. Meet, ultraviolet! The radiation of the Sun contains a few types of emitting, which differ from
5. Let's consider the most common types of UV: UVA (400-315nm) rays have a relatively long wave
6. UVA UVA rays age skin cells and can damage their DNA. These rays are linked to
7. UVB UVB rays have slightly more energy than UVA rays. They can damage skin cells’ DNA
8. UVC UVC rays have more energy than the other types of UV rays, but they don’t
9. What influence do UV rays have on the condition of living things?
10. Photosynthesis UV radiation however causes production of reactive oxygen species (ROS) which may cause various type
12. Health effects The ultraviolet radiation in sunlight has both positive and negative health effects, as it
13. Beneficial outcomes The benefits of UV can outweigh manageable risks. The human body needs some UV
14. Vitamin D Reasonable exposure to ultraviolet radiation from the sun can be a good source of
15. Serotonin Vitamin D promotes the creation of serotonin. The production of serotonin is in direct proportion
16. Melanin The amount of the brown pigment melanin in the skin increases after exposure to UV
17. Effects on eyes Significant daily exposure to bright light may be necessary for children to avoid
18. Harmful effects Excessive exposure to UV radiation can result in acute and chronic harmful effects on
19. Skin damage All bands of UV radiation damage collagen fibers and accelerate aging of the skin.
20. Eye damage Prolonged optical exposure to sunlight, especially intense ultraviolet light, may be linked to cortical
21. UV skin protection SPF stands for sun protection factor. Sunscreens are classified by an SPF number
22. Classic vs. Mineral: Which is Which? Classic and Mineral Sunscreens are differentiated by their active sun
23. The effect of classic suntans is based on chemical reactions by swallowing sun radiation and mineral
24. UV eye protection To decrease the risk of developing eye-related diseases, it may be wise to
25. But what about inanimate objects?
26. Degradation of polymers, pigments and dyes Many natural and synthetic polymers are attacked by ultraviolet radiation,
27. UV damaged polypropylene rope (left) and new rope (right)
28. Applications Because of its ability to cause chemical reactions and excite fluorescence in materials, ultraviolet radiation
29. Photography Photography by reflected ultraviolet radiation is useful for medical, scientific, and forensic investigations, in applications
30. Analytic uses UV is an investigative tool at the crime scene helpful in locating and identifying
31. Air purification Using a catalytic chemical reaction from titanium dioxide and UVC exposure, oxidation of organic
32. Sterilization & disinfection Ultraviolet lamps are used to sterilize workspaces and tools used in biology laboratories
33. Insects trapping Ultraviolet traps called bug zappers are used to eliminate various small flying insects. They
34. Skin conditions UV rays also treat certain skin conditions. Modern phototherapy has been used to successfully
35. Summary findings UV occurs to be the one of nature factors which we only have the
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Research questions:
1.What is ultraviolet?
2. What are its mechanisms?
3. How does it

influence flora & fauna? Inanimate objects?
4. How is it presently applied by human?

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Meet, ultraviolet!
The radiation of the Sun contains a few types of

emitting, which differ from one another in the wavelength. The intermediate radiation, or ultraviolet radiation, is believed to have both benign and pernicious impact on the health of living things. It is able to pass through the atmosphere even in cold and cloudy weather.

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Let's consider the most common types of UV:
UVA (400-315nm) rays have

a relatively long wave length and represent close to 95% of the UV rays that make it to the Earth’s surface .
UVB (315-280nm) have a medium wave length. Only its part passes through the atmosphere.

UVC (280-10nm) are considered to be the most harmful, but they do not reach the Earth’s surface because they are completely filtered by the ozone layer in the atmosphere.

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UVA
UVA rays age skin cells and can damage their DNA. These

rays are linked to long-term skin damage such as wrinkles, but they are also thought to play a role in some skin cancers. Most tanning beds give off large amounts of UVA, which has been found to increase skin cancer risk.

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UVB
UVB rays have slightly more energy than UVA rays. They can

damage skin cells’ DNA directly, and are the main rays that cause sunburns. They are also thought to cause most skin cancers.

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UVC
UVC rays have more energy than the other types of UV

rays, but they don’t get through our atmosphere and are not in sunlight. They are not normally a cause of skin cancer.

Both UVA and UVB rays can damage skin and cause skin cancer. UVB rays are a more potent cause of at least some skin cancers, but based on what’s known today, there are no safe UV rays.

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What influence do UV rays have on the condition of living

things?

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Photosynthesis
UV radiation however causes production of reactive oxygen species (ROS)

which may cause various type of damage to biomolecules. Extreme damage leads to cell death/chlorosis/necrosis and obviously a loss of photosynthetic process.

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Health effects
The ultraviolet radiation in sunlight has both positive and

negative health effects, as it is both a principal source of vitamin D3 and a mutagen.

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Beneficial outcomes
The benefits of UV can outweigh manageable risks. The

human body needs some UV radiation in order for one to maintain adequate level of viability.

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Vitamin D
Reasonable exposure to ultraviolet radiation from the sun can be

a good source of vitamin D. Getting enough vitamin D can help stave off autoimmune diseases, cardiovascular disease, many types of cancer, dementia, types 1 and 2 diabetes mellitus, and respiratory tract infections.

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Serotonin
Vitamin D promotes the creation of serotonin. The production of

serotonin is in direct proportion to the degree of bright sunlight the body receives. Serotonin is a monoamine neurotransmitter that is thought to provide sensations of happiness, well being and serenity to human beings.

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Melanin
The amount of the brown pigment melanin in the skin increases

after exposure to UV radiation at moderate levels depending on skin type. Melanin is an excellent photoprotectant that absorbs both UVB and UVA radiation and dissipates the energy as harmless heat, protecting the skin against DNA damage.

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Effects on eyes
Significant daily exposure to bright light may be

necessary for children to avoid myopia (nearsightedness).

Cardiovascular & hypertension
There are significant archives of studies demonstrating that individuals with more sun exposure synthesize more active vitamin D from their diet, which reduces the possibility of problems with blood pressure.

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Harmful effects
Excessive exposure to UV radiation can result in acute

and chronic harmful effects on the skin, eye, immune system and DNA.

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Skin damage
All bands of UV radiation damage collagen fibers and accelerate

aging of the skin. Both UVA and UVB destroy vitamin A in skin, which may cause further damage. UVB radiation can cause direct DNA damage.

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Eye damage
Prolonged optical exposure to sunlight, especially intense ultraviolet light,

may be linked to cortical cataracts. Short-term over-exposure can cause snow blindness, which is analogous to sunburn of the cornea, or can cause solar retinopathy, which is long-lasting retinal damage and vision impairment from sungazing.

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UV skin protection
SPF stands for sun protection factor. Sunscreens are

classified by an SPF number which refers to their ability to deflect UVB rays. The SPF rating is calculated by comparing the amount of time needed to burn sunscreen-protected skin vs. unprotected skin.

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Classic vs. Mineral: Which is Which?
Classic and Mineral Sunscreens are differentiated

by their active sun protection ingredients. Classic sunscreens use chemical active ingredients designed to absorb and dissipate UVA/UVB rays, while Mineral sunscreens use mineral active ingredients such as Titanium Dioxide and Zinc Oxide to scatter and reflect UVA/UVB rays.

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The effect of classic suntans is based on chemical reactions by

swallowing sun radiation and mineral ones create a protective layer on the skin surface.

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UV eye protection
To decrease the risk of developing eye-related diseases,

it may be wise to wear sunglasses when outdoors, even on overcast days.

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But what about inanimate objects?

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Degradation of polymers, pigments and dyes
Many natural and synthetic polymers are

attacked by ultraviolet radiation, and products using these materials may crack or disintegrate if they are not UV-stable.

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UV damaged polypropylene rope (left) and new rope (right)

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Applications
Because of its ability to cause chemical reactions and excite

fluorescence in materials, ultraviolet radiation has a number of applications.

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Photography
Photography by reflected ultraviolet radiation is useful for medical, scientific,

and forensic investigations, in applications as widespread as detecting bruising of skin, alterations of documents, or restoration work on paintings.

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Analytic uses
UV is an investigative tool at the crime scene helpful

in locating and identifying bodily fluids. Other applications include the authentication of various collectibles and art, and detecting counterfeit currency.

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Air purification
Using a catalytic chemical reaction from titanium dioxide and

UVC exposure, oxidation of organic matter converts pathogens, pollens, and mold spores into harmless inert byproducts.

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Sterilization & disinfection
Ultraviolet lamps are used to sterilize workspaces and tools

used in biology laboratories and medical facilities.
Solar water disinfection has been researched for cheaply treating contaminated water using natural sunlight. The UV-A radiation and increased water temperature kill organisms in the water.

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Insects trapping
Ultraviolet traps called bug zappers are used to eliminate various

small flying insects. They are attracted to the UV and are killed using an electric shock, or trapped once they come into contact with the device. Different designs of ultraviolet radiation traps are also used by entomologists for collecting nocturnal insects during faunistic survey studies.

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Skin conditions
UV rays also treat certain skin conditions. Modern phototherapy

has been used to successfully treat rickets, psoriasis, eczema, jaundice, vitiligo, atopic dermatitis, and localized scleroderma.

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Summary findings
UV occurs to be the one of nature factors

which we only have the opportunity to receive with beneficial and harmful sides bound together.
The effect of the ultraviolet can be used and turned into the tool for the human’s wellbeing.

Ultraviolet radiation (UV)

Содержание

Research questions:1.What is ultraviolet?2. What are its mechanisms?3. How does it

Meet, ultraviolet!The radiation of the Sun contains a few types of

Let's consider the most common types of UV:UVA (400-315nm) rays have

UVAUVA rays age skin cells and can damage their DNA. These

UVBUVB rays have slightly more energy than UVA rays. They can

UVCUVC rays have more energy than the other types of UV

What influence do UV rays have on the condition of living

Photosynthesis UV radiation however causes production of reactive oxygen species (ROS)

Health effects The ultraviolet radiation in sunlight has both positive and

Beneficial outcomes The benefits of UV can outweigh manageable risks. The

Vitamin DReasonable exposure to ultraviolet radiation from the sun can be

Serotonin Vitamin D promotes the creation of serotonin. The production of

MelaninThe amount of the brown pigment melanin in the skin increases

Effects on eyes Significant daily exposure to bright light may be

Harmful effects Excessive exposure to UV radiation can result in acute

Skin damageAll bands of UV radiation damage collagen fibers and accelerate

Eye damage Prolonged optical exposure to sunlight, especially intense ultraviolet light,

UV skin protection SPF stands for sun protection factor. Sunscreens are

Classic vs. Mineral: Which is Which?Classic and Mineral Sunscreens are differentiated