DNA

Deoxyribonucleic acid or DNA, is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms. The main role of DNA molecules is the long-term storage of information. DNA is often compared to a set of blueprints, like a recipe or a code, since it contains the instructions needed to construct other components of cells, such as proteins and RNA molecules. The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in regulating the use of this genetic information.

DNA consists of two long polymers of simple units called nucleotides, with backbones made of sugars and phosphate groups joined by ester bonds. These two strands run in opposite directions to each other and are therefore anti-parallel. Attached to each sugar is one of four types of molecules called bases. It is the sequence of these four bases along the backbone that encodes information. This information is read using the genetic code, which specifies the sequence of the amino acids within proteins. The code is read by copying stretches of DNA into the related nucleic acid RNA, in a process called transcription.

Within cells, DNA is organized into long structures called chromosomes. These chromosomes are duplicated before cells divide, in a process called DNA replication. Eukaryotic organisms (animals, plants, fungi, and protists) store most of their DNA inside the cell nucleus and some of their DNA in organelles, such as mitochondria or chloroplasts.

DNA was first isolated by the Swiss physician Friedrich Miescher who, in 1869, discovered a microscopic substance in the pus of discarded surgical bandages. As it resided in the nuclei of cells, he called it "nuclein". In 1919, Phoebus Levene identified the base, sugar and phosphate nucleotide unit. Levene suggested that DNA consisted of a string of nucleotide units linked together through the phosphate groups. However, Levene thought the chain was short and the bases repeated in a fixed order. In 1937 William Astbury produced the first X-ray diffraction patterns that showed that DNA had a regular structure.

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Aum - The Symbol

Om or Aum, written in Devanāgari as ॐ and as ओम्, in Sanskrit known as pranava प्रणव, is a sacred/mystical syllable in the Dharma or Indian religions, i.e. Hinduism, Jainism, and Buddhism.

Aum is most commonly pronounced as a long or over-long nasalized close-mid back rounded vowel, though there are other enunciations adhered to in received traditions. It is placed at the beginning of most Hindu texts as a sacred incantation to be intoned at the beginning and end of a reading of the Vedas or prior to any prayer or mantra. The Māndukya Upanishad is entirely devoted to the explanation of the syllable. The syllable consists of three phonemes, a Vaishvanara, u Hiranyagarbha and m Iswara, which symbolize the beginning, duration, and dissolution of the universe and the associated gods Brahma, Vishnu, and Shiva, respectively. Aum is pronounced in three sounds - A (aaa) , U (ooooo) and M (mmmmm) and signifies Right (A) and Left (U) Sympathetic Nervous Systems (SNS) and (M) Parasympathetic Nervous System. Right SNS (controlled by Left part of brain) looks after the actional aspect where as the left SNS looks after the emotional aspect of human beings.

The name Omkara is taken as a name of God in the Hindu revivalist Arya Samaj.

The syllable aum is first described as all-encompassing mystical entity in the Upanishads. Today, in all Hindu art and all over India and Nepal, 'aum' can be seen virtually everywhere, a common sign for Hinduism and its philosophy and theology. Hindus believe that as creation began, the divine, all-encompassing consciousness took the form of the first and original vibration manifesting as sound "AUM". Before creation began it was "Shunyākāsha", the emptiness or the void. Shunyākāsha, meaning literally "no sky", is more than nothingness, because everything then existed in a latent state of potentiality.

The vibration of "AUM" symbolizes the manifestation of God in form ("sāguna brahman"). "AUM" is the reflection of the absolute reality, it is said to be "Adi Anadi", without beginning or the end and embracing all that exists. The mantra "AUM" is the name of God, the vibration of the Supreme. When taken letter by letter, A-U-M represents the divine energy (Shakti) united in its three elementary aspects: Bhrahma Shakti (creation), Vishnu Shakti (preservation) and Shiva Shakti (liberation, and/or destruction).

In Jainism, Aum is regarded to be a condensed form of reference to the five parameshthis, by their initials A+A+A+U+M

In Buddhism, Aum is placed at the beginning of their Vidya-Sadaksari or mystical formulary in six syllables as well as most other mantras and dhāranis. As a seed syllable (bija mantra), it is also considered holy in Esoteric Buddhism.

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KITES

A kite is a tethered aircraft. The necessary lift that makes the kite wing fly is generated when air (or in some cases water) flows over and under the kite's wing, producing low pressure above the wing and high pressure below it.

This deflection also generates horizontal drag along the direction of the wind. The resultant force vector from the lift and drag force components is opposed by the tension of the one or more lines or tethers. The anchor point of the kite line may be static or moving (e.g., the towing of a kite by a running person, boat or vehicle).

Kites are usually heavier-than-air, but there is a second category of lighter-than-air kite called a kytoon which may be filled with hydrogen, hot air, methane, or helium; these stay aloft with or without wind; at calm they float; at wind they receive lift from buoyancy and aerodynamic lift. Kytoons have been made in toy-scale as well as military large scale.

Kites may be flown for recreation, art or other practical uses. Sport kites can be flown in aerial ballet, sometimes as part of a competition. Power kites are multi-line steerable kites designed to generate large forces which can be used to power activities such as kite surfing, kite landboarding, kite buggying and a new trend snow kiting. Kites towed behind boats can lift passengers which has had useful military applications in the past.

Kites were used approximately 2,800 years ago in China, where materials ideal for kite building were readily available: silk fabric for sail material; fine, high-tensile-strength silk for flying line; and resilient bamboo for a strong, lightweight framework. Alternatively, the kite authors Clive Hart and Tal Streeter hold that leaf kites existed far before that time in what is now Indonesia, based on their interpretation of cave paintings on Muna Island off Sulawesi. The kite was said to be the invention of the famous 5th century BC Chinese philosophers Mozi and Lu Ban. By at least 549 AD paper kites were being flown, as it was recorded in that year a paper kite was used as a message for a rescue mission. Ancient and medieval Chinese sources list other uses of kites for measuring distances, testing the wind, lifting men, signalling, and communication for military operations. The earliest known Chinese kites were flat (not bowed) and often rectangular. Later, tailless kites incorporated a stabilizing bowline. Kites were decorated with mythological motifs and legendary figures; some were fitted with strings and whistles to make musical sounds while flying.

Stories of kites were brought to Europe by Marco Polo towards the end of the 13th century, and kites were brought back by sailors from Japan and Malaysia in the 16th and 17th centuries.
The period from 1860 to about 1910 became the "golden age of kiting". Kites started to be used for scientific purposes, especially in meteorology, aeronautics, wireless communications and photography; reliable manned kites were developed as well as power kites. Invention of powered airplane diminished interest in kites.World War II saw a limited use of kites for military purposes. Since then they are used mainly for recreation due to a vast improvement in technology.

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