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(SUN II) FACTSHEET Stunting is the impaired growth and development that children experience from poor nutrition, repeated infection and inadequate psychosocial stimulation In response to high stunting prevalence, the global Scaling Up Nutrition (SUN) movement was formed in 2009. Zambia was an early adopter of SUN, joining in 2010 to implement a
- Factsheet: Scaling Up Nutrition (SUN) Phase II - UNICEF
Highlights. This factsheet has been developed to provide a...
- SUN Phase II | UNICEF Zambia
The SUN II programme is a 4-year initiative supporting MCDP...
- Factsheet: Scaling Up Nutrition (SUN) Phase II - UNICEF
Highlights. This factsheet has been developed to provide a guide to the Scaling Up Nutrition Phase II (SUN-II) programme in Zambia. Under MCDP II, the Government of Zambia is building on national momentum around stunting reduction in 36 high priority districts. The UN implements SUN II in 17 districts. SUN II is supported by the United Nations ...
SUN and SUN II classifications differ in their contexts. SUN refers to a nuclear membrane protein involved in inhibiting HIV-1 infection and altering nuclear shape . On the other hand, SUN II is a component of the LINC complex, playing a role in lung cancer progression by inhibiting the Warburg effect and increasing sensitivity to cisplatin .
Sep 1, 2024 · The Short Answer: The solar cycle is the cycle that the Sun’s magnetic field goes through approximately every 11 years. Our Sun is a huge ball of electrically-charged hot gas. This charged gas moves, generating a powerful magnetic field. The Sun's magnetic field goes through a cycle, called the solar cycle.
- Overview
- Physical properties
Sun, star around which Earth and the other components of the solar system revolve. It is the dominant body of the system, constituting more than 99 percent of its entire mass. The Sun is the source of an enormous amount of energy, a portion of which provides Earth with the light and heat necessary to support life. It is part of the "observable universe," the region of space that humans can actually or theoretically observe with the aid of technology. Unlike the observable universe, the universe is possibly infinite.
The Sun is classified as a G2 V star, with G2 standing for the second hottest stars of the yellow G class—of surface temperature about 5,800 kelvins (K)—and the V representing a main sequence, or dwarf, star, the typical star for this temperature class. (G stars are so called because of the prominence of a band of atomic and molecular spectral lines that the German physicist Joseph von Fraunhofer designated G.) The Sun exists in the outer part of the Milky Way Galaxy and was formed from material that had been processed inside a supernova. The Sun is not, as is often said, a small star. Although it falls midway between the biggest and smallest stars of its type, there are so many dwarf stars that the Sun falls in the top 5 percent of stars in the neighbourhood that immediately surrounds it.
The radius of the Sun, R☉, is 109 times that of Earth, but its distance from Earth is 215 R☉, so it subtends an angle of only 1/2° in the sky, roughly the same as that of the Moon. By comparison, Proxima Centauri, the next closest star to Earth, is 250,000 times farther away, and its relative apparent brightness is reduced by the square of that ratio, or 62 billion times. The temperature of the Sun’s surface is so high that no solid or liquid can exist there; the constituent materials are predominantly gaseous atoms, with a very small number of molecules. As a result, there is no fixed surface. The surface viewed from Earth, called the photosphere, is the layer from which most of the radiation reaches us; the radiation from below is absorbed and reradiated, and the emission from overlying layers drops sharply, by about a factor of six every 200 kilometres (124 miles). The Sun is so far from Earth that this slightly fuzzy surface cannot be resolved, and so the limb (the visible edge) appears sharp.
The mass of the Sun, M☉, is 743 times the total mass of all the planets in the solar system and 330,000 times that of Earth. All the interesting planetary and interplanetary gravitational phenomena are negligible effects in comparison to the force exerted by the Sun. Under the force of gravity, the great mass of the Sun presses inward, and to keep the star from collapsing, the central pressure outward must be great enough to support its weight. The density at the Sun’s core is about 100 times that of water (roughly six times that at the centre of Earth), but the temperature is at least 15,000,000 K, so the central pressure is at least 10,000 times greater than that at the centre of Earth, which is 3,500 kilobars. The nuclei of atoms are completely stripped of their electrons, and at this high temperature they collide to produce the nuclear reactions that are responsible for generating the energy vital to life on Earth.
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While the temperature of the Sun drops from 15,000,000 K at the centre to 5,800 K at the photosphere, a surprising reversal occurs above that point; the temperature drops to a minimum of 4,000 K, then begins to rise in the chromosphere, a layer about 7,000 kilometres high at a temperature of 8,000 K. During a total eclipse the chromosphere appears as a pink ring. Above the chromosphere is a dim, extended halo called the corona, which has a temperature of 1,000,000 K and reaches far past the planets. Beyond a distance of 5R☉ from the Sun, the corona flows outward at a speed (near Earth) of 400 kilometres per second (km/s); this flow of charged particles is called the solar wind.
The Sun is a very stable source of energy; its radiative output, called the solar constant, is 1.366 kilowatts per square metre at Earth and varies by no more than 0.1 percent. Superposed on this stable star, however, is an interesting 11-year cycle of magnetic activity manifested by regions of transient strong magnetic fields called sunspots.
The SUN II programme is a 4-year initiative supporting MCDP II led by UNICEF in partnership with the National Food and Nutrition Commission, line ministries, other UN agencies, and non-governmental organizations. The programme is generously supported by the European Union, the Federal Republic of Germany through KFW Development Bank, the ...
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The Sun is the star at the center of the Solar System. ... relative to the abundances of these elements in so-called Population II, heavy-element-poor, stars.
