Sunlight

Sunlight is a portion of the electromagnetic radiation given off by the Sun, in particular infrared, visible, and ultraviolet light. On Earth, sunlight is filtered through Earth's atmosphere, and is obvious as daylight when the Sun is above the horizon. When the direct solar radiation is not blocked by clouds, it is experienced as sunshine, a combination of bright light and radiant heat. When it is blocked by the clouds or reflects off other objects, it is experienced as diffused light. The World Meteorological Organization uses the term "sunshine duration" to mean the cumulative time during which an area receives direct irradiance from the Sun of at least 120 watts per square meter.

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.

Summary

Researchers may record sunlight using a sunshine recorder, pyranometer, or pyrheliometer.

Sunlight takes about 8.3 minutes to reach Earth from the surface of the Sun. A photon starting at the centre of the Sun and changing direction every time it encounters a charged particle would take between 10,000 and 170,000 years to get to the surface.

Sunshine (The Archies album)

Sunshine is the fourth studio album released by The Archies, a fictional bubblegum pop band of The Archie Show and the Archie Comics universe. The album includes 12 tracks and was issued on Kirshner Records. It was produced by Jeff Barry. The album features the single "Sunshine". The song peaked at number 57 on the Billboard Hot 100. The album peaked at number 137 on the Billboard Top LPs chart.

Track listing

Charts

References

Sunshine (Jonathan Edwards song)

"Sunshine" is a country folk song from 1971 by Jonathan Edwards, released as the first single from his debut album Jonathan Edwards. The single reached Billboard #4 and earned a gold record.

"Sunshine" was not originally planned for release, but when an engineer accidentally erased the master of a track called "Please Find Me" near the end of sessions for the album, "Sunshine" was used to fill the hole.

The song was released as a single and first gained popularity on Boston radio, then nationwide, hitting #4 on the Billboard Hot 100 chart on January 15, 1972 and earning a gold record. Here's Edwards' take on its success: "It was just at the time of the Vietnam War and Nixon. It was looking bad out there. That song meant a lot to a lot of people during that time--especially me."

Chart positions

Covers

In 1980, Juice Newton scored a Top-40 hit, peaking at #35 on the Billboard Country chart with her version of "Sunshine".

Helix

A helix (pl: helixes or helices) is a type of smooth space curve, i.e. a curve in three-dimensional space. It has the property that the tangent line at any point makes a constant angle with a fixed line called the axis. Examples of helices are coil springs and the handrails of spiral staircases. A "filled-in" helix – for example, a spiral ramp – is called a helicoid. Helices are important in biology, as the DNA molecule is formed as two intertwined helices, and many proteins have helical substructures, known as alpha helices. The word helix comes from the Greek word ἕλιξ, "twisted, curved".

Types

Helices can be either right-handed or left-handed. With the line of sight along the helix's axis, if a clockwise screwing motion moves the helix away from the observer, then it is called a right-handed helix; if towards the observer, then it is a left-handed helix. Handedness (or chirality) is a property of the helix, not of the perspective: a right-handed helix cannot be turned to look like a left-handed one unless it is viewed in a mirror, and vice versa.

Helix (comics)

Helix was a short-lived, science fiction and science fantasy imprint of DC Comics, launched in 1996 and discontinued in 1998. In early promotional materials prior to the release of the first title, the imprint was called Matrix instead of Helix. It was renamed because of the then-upcoming film, The Matrix. It featured a handful of ongoing monthly series, several limited series, and one short graphic novel.

Despite the involvement of successful science fiction/fantasy novelists Michael Moorcock, Lucius Shepard and Christopher Hinz, and established comics creators Howard Chaykin, Elaine Lee, Matt Howarth, Warren Ellis, Walt Simonson, and Garth Ennis, sales of the comic books were low, and most of the ongoing titles were cancelled after 12 or fewer issues. Ellis' Transmetropolitan was switched to the Vertigo imprint, where it continued for several more years before reaching its planned conclusion. Ennis' Bloody Mary mini-series and Michael Moorcock's Multiverse were later collected in Vertigo-label paperbacks and Moeller's Sheva's War was released as a graphic novel paperback by Dark Horse.

Pi helix

A pi helix (or π-helix) is a type of secondary structure found in proteins. Although once thought to be rare, short π-helices are found in 15% of known protein structures and are believed to be an evolutionary adaptation derived by the insertion of a single amino acid into an α-helix. Because such insertions are highly destabilizing, the formation of π-helices would tend to be selected against unless it provided some functional advantage to the protein. π-helices therefore are typically found near functional sites of proteins.

Standard structure

The amino acids in a standard π-helix are arranged in a right-handed helical structure. Each amino acid corresponds to an 87° turn in the helix (i.e., the helix has 4.1 residues per turn), and a translation of 1.15 Å (=0.115 nm) along the helical axis. Most importantly, the N-H group of an amino acid forms a hydrogen bond with the C=O group of the amino acid five residues earlier; this repeated i+5→i hydrogen bonding defines a π-helix. Similar structures include the 3₁₀ helix (i+3→i hydrogen bonding) and the α-helix (i+4→i hydrogen bonding).