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#1 Re: This is Cool » Miscellany » Today 01:18:10

637) Cavities/tooth decay

Overview

Cavities are permanently damaged areas in the hard surface of your teeth that develop into tiny openings or holes. Cavities, also called tooth decay or caries, are caused by a combination of factors, including bacteria in your mouth, frequent snacking, sipping sugary drinks and not cleaning your teeth well.

Cavities and tooth decay are among the world's most common health problems. They're especially common in children, teenagers and older adults. But anyone who has teeth can get cavities, including infants.

If cavities aren't treated, they get larger and affect deeper layers of your teeth. They can lead to a severe toothache, infection and tooth loss. Regular dental visits and good brushing and flossing habits are your best protection against cavities and tooth decay.

Symptoms

The signs and symptoms of cavities vary, depending on their extent and location. When a cavity is just beginning, you may not have any symptoms at all. As the decay gets larger, it may cause signs and symptoms such as:

•    Toothache, spontaneous pain or pain that occurs without any apparent cause
•    Tooth sensitivity
•    Mild to sharp pain when eating or drinking something sweet, hot or cold
•    Visible holes or pits in your teeth
•    Brown, black or white staining on any surface of a tooth
•    Pain when you bite down

When to see a dentist

You may not be aware that a cavity is forming. That's why it's important to have regular dental checkups and cleanings, even when your mouth feels fine. However, if you experience a toothache or mouth pain, see your dentist as soon as possible.

Causes

Cavities are caused by tooth decay — a process that occurs over time. Here's how tooth decay develops:
•    Plaque forms. Dental plaque is a clear sticky film that coats your teeth. It's due to eating a lot of sugars and starches and not cleaning your teeth well. When sugars and starches aren't cleaned off your teeth, bacteria quickly begin feeding on them and form plaque. Plaque that stays on your teeth can harden under or above your gum line into tartar (calculus). Tartar makes plaque more difficult to remove and creates a shield for bacteria.
•    Plaque attacks. The acids in plaque remove minerals in your tooth's hard, outer enamel. This erosion causes tiny openings or holes in the enamel — the first stage of cavities. Once areas of enamel are worn away, the bacteria and acid can reach the next layer of your teeth, called dentin. This layer is softer than enamel and less resistant to acid. Dentin has tiny tubes that directly communicate with the nerve of the tooth causing sensitivity.
•    Destruction continues. As tooth decay develops, the bacteria and acid continue their march through your teeth, moving next to the inner tooth material (pulp) that contains nerves and blood vessels. The pulp becomes swollen and irritated from the bacteria. Because there is no place for the swelling to expand inside of a tooth, the nerve becomes pressed, causing pain. Discomfort can even extend outside of the tooth root to the bone.

Risk factors

Everyone who has teeth is at risk of getting cavities, but the following factors can increase risk:

•    Tooth location. Decay most often occurs in your back teeth (molars and premolars). These teeth have lots of grooves, pits and crannies, and multiple roots that can collect food particles. As a result, they're harder to keep clean than your smoother, easy-to-reach front teeth.
•    Certain foods and drinks. Foods that cling to your teeth for a long time — such as milk, ice cream, honey, sugar, soda, dried fruit, cake, cookies, hard candy and mints, dry cereal, and chips — are more likely to cause decay than foods that are easily washed away by saliva.
•    Frequent snacking or sipping. When you steadily snack or sip sugary drinks, you give mouth bacteria more fuel to produce acids that attack your teeth and wear them down. And sipping soda or other acidic drinks throughout the day helps create a continual acid bath over your teeth.
•    Bedtime infant feeding. When babies are given bedtime bottles filled with milk, formula, juice or other sugar-containing liquids, these beverages remain on their teeth for hours while they sleep, feeding decay-causing bacteria. This damage is often called baby bottle tooth decay. Similar damage can occur when toddlers wander around drinking from a sippy cup filled with these beverages.
•    Inadequate brushing. If you don't clean your teeth soon after eating and drinking, plaque forms quickly and the first stages of decay can begin.
•    Not getting enough fluoride. Fluoride, a naturally occurring mineral, helps prevent cavities and can even reverse the earliest stages of tooth damage. Because of its benefits for teeth, fluoride is added to many public water supplies. It's also a common ingredient in toothpaste and mouth rinses. But bottled water usually does not contain fluoride.
•    Younger or older age. In the United States, cavities are common in very young children and teenagers. Older adults also are at higher risk. Over time, teeth can wear down and gums may recede, making teeth more vulnerable to root decay. Older adults also may use more medications that reduce saliva flow, increasing the risk of tooth decay.
•    Dry mouth. Dry mouth is caused by a lack of saliva, which helps prevent tooth decay by washing away food and plaque from your teeth. Substances found in saliva also help counter the acid produced by bacteria. Certain medications, some medical conditions, radiation to your head or neck, or certain chemotherapy drugs can increase your risk of cavities by reducing saliva production.
•    Worn fillings or dental devices. Over the years, dental fillings can weaken, begin to break down or develop rough edges. This allows plaque to build up more easily and makes it harder to remove. Dental devices can stop fitting well, allowing decay to begin underneath them.
•    Heartburn. Heartburn or gastroesophageal reflux disease (GERD) can cause stomach acid to flow into your mouth (reflux), wearing away the enamel of your teeth and causing significant tooth damage. This exposes more of the dentin to attack by bacteria, creating tooth decay. Your dentist may recommend that you consult your doctor to see if gastric reflux is the cause of your enamel loss.
•    Eating disorders. Anorexia and bulimia can lead to significant tooth erosion and cavities. Stomach acid from repeated vomiting (purging) washes over the teeth and begins dissolving the enamel. Eating disorders also can interfere with saliva production.

Complications

Cavities and tooth decay are so common that you may not take them seriously. And you may think that it doesn't matter if children get cavities in their baby teeth. However, cavities and tooth decay can have serious and lasting complications, even for children who don't have their permanent teeth yet.
Complications of cavities may include:

•    Pain
•    Tooth abscess
•    Swelling or pus around a tooth
•    Damage or broken teeth
•    Chewing problems
•    Positioning shifts of teeth after tooth loss

When cavities and decay become severe, you may have:

•    Pain that interferes with daily living
•    Weight loss or nutrition problems from painful or difficult eating or chewing
•    Tooth loss, which may affect your appearance, as well as your confidence and self-esteem
•    In rare cases, a tooth abscess — a pocket of pus that's caused by bacterial infection — which can lead to more serious or even life-threatening infections

Prevention

Good oral and dental hygiene can help you avoid cavities and tooth decay. Here are some tips to help prevent cavities. Ask your dentist which tips are best for you.

•    Brush with fluoride toothpaste after eating or drinking. Brush your teeth at least twice a day and ideally after every meal, using fluoride-containing toothpaste. To clean between your teeth, floss or use an interdental cleaner.
•    Rinse your mouth. If your dentist feels you have a high risk of developing cavities, he or she may recommend that you use a mouth rinse with fluoride.
•    Visit your dentist regularly. Get professional teeth cleanings and regular oral exams, which can help prevent problems or spot them early. Your dentist can recommend a schedule that's best for you.
•    Consider dental sealants. A sealant is a protective plastic coating applied to the chewing surface of back teeth. It seals off grooves and crannies that tend to collect food, protecting tooth enamel from plaque and acid. The Centers for Disease Control and Prevention (CDC) recommends sealants for all school-age children. Sealants may last for several years before they need to be replaced, but they need to be checked regularly.
•    Drink some tap water. Most public water supplies have added fluoride, which can help reduce tooth decay significantly. If you drink only bottled water that doesn't contain fluoride, you'll miss out on fluoride benefits.
•    Avoid frequent snacking and sipping. Whenever you eat or drink beverages other than water, you help your mouth bacteria create acids that can destroy tooth enamel. If you snack or drink throughout the day, your teeth are under constant attack.
•    Eat tooth-healthy foods. Some foods and beverages are better for your teeth than others. Avoid foods that get stuck in grooves and pits of your teeth for long periods, or brush soon after eating them. However, foods such as fresh fruits and vegetables increase saliva flow, and unsweetened coffee, tea and sugar-free gum help wash away food particles.
•    Consider fluoride treatments. Your dentist may recommend periodic fluoride treatments, especially if you aren't getting enough fluoride through fluoridated drinking water and other sources. He or she may also recommend custom trays that fit over your teeth for application of prescription fluoride if your risk of tooth decay is very high.
•    Ask about antibacterial treatments. If you're especially vulnerable to tooth decay — for example, because of a medical condition — your dentist may recommend special antibacterial mouth rinses or other treatments to help cut down on harmful bacteria in your mouth.
•    Combined treatments. Chewing xylitol-based gum along with prescription fluoride and an antibacterial rinse can help reduce the risk of cavities.

How-To-Stop-Tooth-Pain.jpg

#2 Re: Dark Discussions at Cafe Infinity » crème de la crème » Today 00:53:10

737) Yvonne Brill

Yvonne Brill, (Yvonne Madelaine Claeys), Canadian-born American rocket scientist (born Dec. 30, 1924, St. Vital, Man.—died March 27, 2013, Princeton, N.J.), pioneered the electrothermal hydrazine thruster—a more fuel-efficient rocket thruster designed to keep communications satellites from slipping out of orbit. Brill was not admitted to the men-only engineering department at the University of Manitoba, but she graduated (1945) at the top of her class with degrees in chemistry and mathematics. (She later received a master’s degree [1951] in chemistry from the University of Southern California.) Despite her lack of an engineering degree, she was recruited (1945) by Douglas Aircraft (which became the basis for the RAND Corporation) in Santa Monica, Calif., to help create the first designs for an American satellite. Throughout that period she was believed to be the only woman in the U.S. conducting research in the field of rocket science. Brill put her career on hold in the late 1950s to stay home with her children, but she returned (1966) to work full-time for RCA’s rocket subsidiary, where she developed the thruster that rapidly became the industry standard. She also was involved in developing the Nova rockets that were used in American Moon missions; Tiros, the first weather satellite; the Atmosphere Explorer, the first upper-atmosphere satellite; and the Mars Observer satellite (1992). While working (1981–83) for NASA, she contributed to the development of a rocket engine for the space shuttle. Brill received numerous awards for her groundbreaking work, and in 2010 she was inducted into the National Inventors Hall of Fame.

Yvonne Madelaine Brill (née Claeys; December 30, 1924 – March 27, 2013) was a Canadian-American rocket and jet propulsion engineer. She is responsible for inventing the fuel-efficient rocket thruster that keeps satellites in orbit today. During her career she was involved in a broad range of national space programs in the United States, including NASA and the International Maritime Satellite Organization.

Early life

Brill was born in Winnipeg, Manitoba, Canada. Her parents were immigrants from Belgium, making her and her two siblings first-generation Canadians. While she was in high school, one of her teachers told her that a woman wouldn't get anywhere in science. Her father wanted her to stay at home and open a little shop in town[4]. She definitely did not listen to them. She attended the University of Manitoba, but was barred from studying engineering because of her gender, so she studied chemistry and mathematics. She graduated at the top of her class in 1945 with a bachelor's degree in chemistry and mathematics. She went on to study at the University of Southern California, where she took night classes and graduated in 1951 with a master's degree in chemistry.

Career

Brill's work in satellite propulsion systems resulted in a number of significant developments. She developed the concept for a new rocket engine, the hydrazine resistojet, and proposed the use of a single propellant because of the value and simplicity that it would provide. Her invention resulted in not only higher engine performance, but also increased the reliability of the propulsion system. The reduction in propellant weight requirements enabled either increased payload capability or extended mission life.

Brill was believed to be the only woman in the United States researching rocket science in the 1940s. In 1945 she was recruited by Douglas Aircraft despite her lack of a degree in engineering to help develop the first American satellites. She put her career on hold in the 1950s to stay at home and raise her children. Then in 1966 she returned to the field, where she rejoined the Radio Corporation of America (RCA).

Brill invented the hydrazine resistojet propulsion system in 1967, for which she holds U.S. Patent No. 3,807,657. Her invention became a standard in the industry and has translated into millions of dollars of increased revenue for commercial communications satellite owners.

Brill contributed to the propulsion systems of TIROS, the first weather satellite; Nova, a series of rocket designs that were used in American Moon missions; Explorer 32, the first upper-atmosphere satellite; and the Mars Observer, which in 1992 almost entered a Mars orbit before losing communication with Earth.

Awards and honors

Brill was awarded the AIAA Wyld Propulsion Award (2002) and the American Association of Engineering Societies John Fritz Medal (2009). In 1980, Harper's Bazaar and the DeBeers Corporation gave her their Diamond Superwoman award for returning to a successful career after starting a family. In 2001 she was awarded the NASA Distinguished Public Service Medal.[10] In 2010 President Barack Obama presented her with the National Medal of Technology and Innovation. In 2010 she was also inducted into the National Inventors Hall of Fame.

She was elected to the National Academy of Engineering in 1987. She was named fellow of The Society of Women Engineers (SWE) in 1985 and received its highest honor, the Achievement Award, the following year.

The Yvonne C. Brill Lectureship of the American Institute of Aeronautics and Astronautics (AIAA) is named in her honor and presented annually.

As her life dwindled down, she spent the last twenty years promoting women in science and engineering and nominated them for awards and prizes she thought they deserved.

Death

A longtime resident of the Skillman section of Montgomery Township, New Jersey, United States, Brill died of complications of breast cancer in Princeton, New Jersey.

An obituary of Brill published in the March 30, 2013 issue of the New York Times originally began: "She made a mean beef stroganoff, followed her husband from job to job and took eight years off from work to raise three children". The obituary was heavily criticized for leading with and overemphasizing Brill's gender and family life, rather than her scientific and career accomplishments and was cited as an example of an article that failed the Finkbeiner test. The Times later dropped the reference to her cooking and changed the lead of the article.

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#3 Re: Ganesh's Puzzles » Doc, Doc! » Today 00:17:53

Hi,

#1503. What does the medical term 'Diaphragm' signify?

#4 Re: Ganesh's Puzzles » 10 second questions » Today 00:04:21

Hi,

#7800. 35% of a number is two times 75% of another number. What is the ratio of the first and second numbers respectively?

#5 Re: Exercises » Compute the solution: » Yesterday 14:45:03

Neat work!

723. Find the nature of the roots of the quadratic equation

#6 Re: This is Cool » Miscellany » Yesterday 01:28:32

636) Metamorphic Rocks

Metamorphic rocks start as one type of rock an - with pressure, heat, and time - gradually change into a new type of rock.

The term “metamorphosis” is most often used in reference to the process of a caterpillar changing into a butterfly. However, the word “metamorphosis” is a broad term that indicates a change from one thing to another. Even rocks, a seemingly constant substance, can change into a new type of rock. Rocks that undergo a change to form a new rock are referred to as metamorphic rocks.

In the rock cycle, there are three different types of rocks: sedimentary, igneous, and metamorphic. Sedimentary and igneous rocks began as something other than rock. Sedimentary rocks were originally sediments, which were compacted under high pressure. Igneous rocks formed when liquid magma or lav - magma that has emerged onto the surface of the Earth - cooled and hardened. A metamorphic rock, on the other hand, began as a rock - either a sedimentary, igneous, or even a different sort of metamorphic rock. Then, due to various conditions within the Earth, the existing rock was changed into a new kind of metamorphic rock.

The conditions required to form a metamorphic rock are very specific. The existing rock must be exposed to high heat, high pressure, or to a hot, mineral-rich fluid. Usually, all three of these circumstances are met. These conditions are most often found either deep in Earth’s crust or at plate boundaries where tectonic plates collide. In order to create metamorphic rock, it is vital that the existing rock remain solid and not melt. If there is too much heat or pressure, the rock will melt and become magma. This will result in the formation of an igneous rock, not a metamorphic rock.

Consider how granite changes form. Granite is an igneous rock that forms when magma cools relatively slowly underground. It is usually composed primarily of the minerals quartz, feldspar, and mica. When granite is subjected to intense heat and pressure, it changes into a metamorphic rock called gneiss.
Slate is another common metamorphic rock that forms from shale. Limestone, a sedimentary rock, will change into the metamorphic rock marble if the right conditions are met.

Although metamorphic rocks typically form deep in the planet’s crust, they are often exposed on the surface of the Earth. This happens due to geologic uplift and the erosion of the rock and soil above them. At the surface, metamorphic rocks will be exposed to weathering processes and may break down into sediment. These sediments could then be compressed to form sedimentary rocks, which would start the entire cycle anew.

1852-schist.jpg

#7 Re: Ganesh's Puzzles » General Quiz » Yesterday 00:46:25

Hi,

#7603. What is Autophobia? (Autophobia, also called monophobia, isolophobia, or eremophobia)

#7604. What does the term basophobia (or basiphobia) mean?

#8 Re: Help Me ! » Percentage Change » Yesterday 00:27:26

Hi sybil8464,

Welcome to the forum!

Original value = 304,000.
Reduced value = 232,000.
Difference = 72,000 decrease.
Percentage decrease = -23.68% approximately, roughly -23.7%.

#9 Re: Ganesh's Puzzles » Oral puzzles » Yesterday 00:15:35

Hi,

#4810. What is 10% of 20% of 25% of 200?

#10 Re: Ganesh's Puzzles » English language puzzles » Yesterday 00:05:05

Hi,

#3639. What does the noun equerry mean?

#3640. What does the noun equestrian mean?

#12 Re: This is Cool » Miscellany » 2020-08-09 00:46:42

635) Igneous Rocks

Igneous rocks are one of three main types of rocks (along with sedimentary and metamorphic), and they include both intrusive and extrusive rocks.

Igneous rocks form when magma (molten rock) cools and crystallizes, either at volcanoes on the surface of the Earth or while the melted rock is still inside the crust. All magma develops underground, in the lower crust or upper mantle, because of the intense heat there.

Igneous rocks can have many different compositions, depending on the magma they cool from. They can also look different based on their cooling conditions. For example, two rocks from identical magma can become either rhyolite or granite, depending on whether they cool quickly or slowly.

The two main categories of igneous rocks are extrusive and intrusive. Extrusive rocks are formed on the surface of the Earth from lava, which is magma that has emerged from underground. Intrusive rocks are formed from magma that cools and solidifies within the crust of the planet.

When lava comes out of a volcano and solidifies into extrusive igneous rock, also called volcanic, the rock cools very quickly. Crystals inside solid volcanic rocks are small because they do not have much time to form until the rock cools all the way, which stops the crystal growth. These fine-grained rocks are known as aphaniti - from a Greek word meaning “invisible.” They are given this name because the crystals that form within them are so small that they can be seen only with a microscope. If lava cools almost instantly, the rocks that form are glassy with no individual crystals, like obsidian. There are many other kinds of extrusive igneous rocks. For example, Pele’s hair is long, extremely thin strands of volcanic glass, while pahoehoe is smooth lava that forms shiny, rounded piles.

Intrusive rocks, also called plutonic rocks, cool slowly without ever reaching the surface. They have large crystals that are usually visible without a microscope. This surface is known as a phaneritic texture. Perhaps the best-known phaneritic rock is granite. One extreme type of phaneritic rock is called pegmatite, found often in the U.S. state of Maine. Pegmatite can have a huge variety of crystal shapes and sizes, including some larger than a human hand.

8b69b1f155e44772b8ae1ed6657b59a6.jpg

#13 Re: Dark Discussions at Cafe Infinity » crème de la crème » 2020-08-09 00:30:19

736) Christiane Nüsslein-Volhard

Christiane Nüsslein-Volhard, (born October 20, 1942, Magdeburg, Germany), German developmental geneticist who was jointly awarded the 1995 Nobel Prize for Physiology or Medicine with geneticists Eric F. Wieschaus and Edward B. Lewis for their research concerning the mechanisms of early embryonic development. Nüsslein-Volhard, working in tandem with Wieschaus, expanded upon the pioneering work of Lewis, who used the fruit fly, or vinegar fly (‘Drosophila melanogaster’), as an experimental subject. Her work has relevance to the development of all multicellular organisms, including humans.

At Eberhard-Karl University of Tübingen, Nüsslein-Volhard received a diploma in biochemistry in 1968 and a doctorate in genetics in 1973. After holding fellowships in Basel and Freiburg, she joined Wieschaus as a group leader at the European Molecular Biology Laboratory in Heidelberg in 1978. In 1981 she returned to Tübingen, where she served as director of the Max Planck Institute for Developmental Biology from 1985 to 2015.

At Heidelberg, Nüsslein-Volhard and Wieschaus spent more than a year crossbreeding 40,000 fruit fly families and systematically examining their genetic makeup at a dual microscope. Their trial-and-error methods resulted in the discovery that of the fly’s 20,000 genes, about 5,000 are deemed important to early development and about 140 are essential. They assigned responsibility for the fruit fly’s embryonic development to three genetic categories: gap genes, which lay out the head-to-tail body plan; pair-rule genes, which determine body segmentation; and segment-polarity genes, which establish repeating structures within each segment.

In the early 1990s Nüsslein-Volhard began studying genes that control development in the zebra fish ‘Danio rerio’. These organisms are ideal models for investigations into developmental biology because they have clear embryos, have a rapid rate of reproduction, and are closely related to other vertebrates. Nüsslein-Volhard studied the migration of cells from their sites of origin to their sites of destination within zebra fish embryos. Her investigations in zebra fish have helped elucidate genes and other cellular substances involved in human development and in the regulation of normal human physiology.

In addition to the Nobel Prize, Nüsslein-Volhard received the Leibniz Prize (1986) and the Albert Lasker Basic Medical Research Award (1991). She also published several books, including  ‘Zebrafish: A Practical Approach’ (2002; written with Ralf Dahm) and ‘Coming to Life: How Genes Drive Development’ (2006).

Christiane_Nusslein_Volhard.jpg

#14 Re: Ganesh's Puzzles » Doc, Doc! » 2020-08-09 00:19:54

Hi,

#1502. What are 'Paschen bodies'?

#15 Re: Ganesh's Puzzles » 10 second questions » 2020-08-09 00:07:59

Hi,

#7799. When the price of a television increases by 12%, the revenue decreases by 5%. Find the percentage change in the number of units of television.

#16 Re: Ganesh's Puzzles » Mensuration » 2020-08-08 15:04:30

Hi,

Excellent!

M # 601. A solid sphere of radius 7 centimeters is melted and recast into a cone of same radius of the sphere. Calculate the height of the cone.

#17 Re: Exercises » Compute the solution: » 2020-08-08 14:48:23

Neat work!

721. If

is a zero of the cubic polynomial
then find its other two zeroes.

#18 Re: This is Cool » Miscellany » 2020-08-08 01:00:46

634) Sedimentary Rocks

Sedimentary rocks are one of three main types of rocks, along with igneous and metamorphic. They are formed on or near the Earth’s surface from the compression of ocean sediments or other processes.

Sedimentary rocks are formed on or near the Earth’s surface, in contrast to metamorphic and igneous rocks, which are formed deep within the Earth. The most important geological processes that lead to the creation of sedimentary rocks are erosion, weathering, dissolution, precipitation, and lithification.

Erosion and weathering include the effects of wind and rain, which slowly break down large rocks into smaller ones. Erosion and weathering transform boulders and even mountains into sediments, such as sand or mud. Dissolution is a form of weathering—chemical weathering. With this process, water that is slightly acidic slowly wears away stone. These three processes create the raw materials for new, sedimentary rocks.

Precipitation and lithification are processes that build new rocks or minerals. Precipitation is the formation of rocks and minerals from chemicals that precipitate from water. For example, as a lake dries up over many thousands of years, it leaves behind mineral deposits; this is what happened in California’s Death Valley. Finally, lithification is the process by which clay, sand, and other sediments on the bottom of the ocean or other bodies of water are slowly compacted into rocks from the weight of overlying sediments.

Sedimentary rocks can be organized into two categories. The first is detrital rock, which comes from the erosion and accumulation of rock fragments, sediment, or other materials—categorized in total as detritus, or debris. The other is chemical rock, produced from the dissolution and precipitation of minerals.

Detritus can be either organic or inorganic. Organic detrital rocks form when parts of plants and animals decay in the ground, leaving behind biological material that is compressed and becomes rock. Coal is a sedimentary rock formed over millions of years from compressed plants. Inorganic detrital rocks, on the other hand, are formed from broken up pieces of other rocks, not from living things. These rocks are often called clastic sedimentary rocks. One of the best-known clastic sedimentary rocks is sandstone. Sandstone is formed from layers of sandy sediment that is compacted and lithified.

Chemical sedimentary rocks can be found in many places, from the ocean to deserts to caves. For instance, most limestone forms at the bottom of the ocean from the precipitation of calcium carbonate and the remains of marine animals with shells. If limestone is found on land, it can be assumed that the area used to be under water. Cave formations are also sedimentary rocks, but they are produced very differently. Stalagmites and stalactites form when water passes through bedrock and picks up calcium and carbonate ions. When the chemical-rich water makes its way into a cave, the water evaporates and leaves behind calcium carbonate on the ceiling, forming a stalactite, or on the floor of the cave, creating a stalagmite.

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#19 Re: Ganesh's Puzzles » General Quiz » 2020-08-08 00:47:02

Hi,

#7601. What does the term 'aerolithology' mean?

#7602. What does the term 'agathology' mean?

#20 Re: Ganesh's Puzzles » Oral puzzles » 2020-08-08 00:31:26

Hi,

#4809. If 10% of a number is 70, then what is 25% of that number?

#21 Re: Ganesh's Puzzles » English language puzzles » 2020-08-08 00:20:45

Hi,

#3637. What does the noun eponym mean?

#3638. What does the noun equanimity mean?

#22 Re: Ganesh's Puzzles » Coordinate Geometry » 2020-08-08 00:03:55

Hi,

Neat work!

CG # 118. Show that A(6,4), B(5,-2), and C(7,-2) are the vertices of an isosceles triangle.

#23 Re: Exercises » Compute the solution: » 2020-08-07 15:06:32

Neat work!

720. If

is a factor of the cubic polynomial
find all the zeroes of the polynomial.

#24 Jokes » A Few More Cow Jokes - 5 » 2020-08-07 02:10:16

ganesh
Replies: 0

Q: Where do Russians get their milk?
A: From Mos-cows.
* * *
Q: Did you hear about the snobby cow?
A: She thought she was a cutlet above the rest!
* * *
Q: What did the cow say to the turtle?
A: Get a moove on.
* * *
Q: What do you call a cow that's afraid of the dark?
A: A coward.
* * *
Q: How does one cow talk to another?
A: Cow-munication.
* * *
Q: What do call a cow that has just had a calf?
A: Decalfenated
* * *
Q: Where do cows get their weapons?
A: Ar-moooo-ries.
* * *

#25 Re: This is Cool » Miscellany » 2020-08-07 00:45:43

633) Sinusitis

Sinusitis, acute or chronic inflammation of the mucosal lining of one or more paranasal sinuses (the cavities in the bones that adjoin the nose). Sinusitis commonly accompanies upper respiratory viral infections and in most cases requires no treatment. Purulent (pus-producing) sinusitis can occur, however, requiring treatment with antibiotics. Chronic cases caused by irritants in the environment or by impaired immune systems may require more extended treatment, including surgery.

The origin of acute sinus infection is much like that of ear infection. Normally the middle ear and the sinuses are sterile, but the adjacent mouth and nose have a varied bacterial flora. Under normal conditions, very small hairs called cilia move mucus along the lining of the nose and respiratory tract, keeping the sinuses clean. When ciliary function is damaged, infection can be established. Following a common cold, a decrease in ciliary function may permit bacteria to remain on the mucous membrane surfaces within the sinuses and to produce a purulent sinusitis. The organisms usually involved are Haemophilus influenzae, Streptococcus pneumoniae, Staphylococcus aureus, Streptococcus pyogenes, and many other penicillin-sensitive anaerobes. Common symptoms include facial pain, headache, and fever following previous upper respiratory viral illness. On physical examination, persons with sinusitis are usually found to have an elevation in body temperature, nasal discharge, and sinus tenderness. Diagnosis can be confirmed by X-rays of the sinuses and cultures of material obtained from within the sinuses.

Treatment of acute sinusitis is directed primarily at overcoming the infecting organism by the use of systemic antibiotics such as penicillin and at encouraging drainage of the sinuses by the use of vasoconstricting nose drops and inhalations. If the infection persists, the pus localized in any individual sinus may have to be removed by means of a minor surgical procedure known as lavage, in which the maxillary or sphenoidal sinuses are irrigated with water or a saline solution.

Chronic sinusitis may follow repeated or neglected attacks of acute sinusitis, particularly if there is impaired breathing or drainage due to nasal polyps or obstructed sinus openings. It may also be caused by allergy to agents in the environment, such as fungi or pollen. The symptoms of chronic sinusitis are a tendency to colds, purulent nasal discharge, obstructed breathing, loss of smell, and sometimes headache. Pain is not a feature of chronic sinusitis. If antibiotic therapy or repeated lavage do not alleviate the condition, steroidal medications may be given to relieve swelling and antihistamines to relieve allergic reactions. In severe cases endoscopic surgery may be necessary to remove obstructions.

sinus.jpg

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