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Electromagnetic spectrum

The electromagnetic spectrum is the range of frequencies of electromagnetic radiation and their respective wavelengths and photon energies. The electromagnetic spectrum covers electromagnetic waves with frequencies ranging from below one hertz to above 1025 hertz, corresponding to wavelengths from thousands of kilometers down to a fraction of the size of an atomic nucleus; this frequency range is divided into separate bands, the electromagnetic waves within each frequency band are called by different names. The electromagnetic waves in each of these bands have different characteristics, such as how they are produced, how they interact with matter, their practical applications; the limit for long wavelengths is the size of the universe itself, while it is thought that the short wavelength limit is in the vicinity of the Planck length. Gamma rays, X-rays, high ultraviolet are classified as ionizing radiation as their photons have enough energy to ionize atoms, causing chemical reactions. In most of the frequency bands above, a technique called spectroscopy can be used to physically separate waves of different frequencies, producing a spectrum showing the constituent frequencies.

Spectroscopy is used to study the interactions of electromagnetic waves with matter. Other technological uses are described under electromagnetic radiation. For most of history, visible light was the only known part of the electromagnetic spectrum; the ancient Greeks recognized that light traveled in straight lines and studied some of its properties, including reflection and refraction. The study of light continued, during the 16th and 17th centuries conflicting theories regarded light as either a wave or a particle; the first discovery of electromagnetic radiation other than visible light came in 1800, when William Herschel discovered infrared radiation. He was studying the temperature of different colors by moving a thermometer through light split by a prism, he noticed. He theorized that this temperature change was due to "calorific rays", a type of light ray that could not be seen; the next year, Johann Ritter, working at the other end of the spectrum, noticed what he called "chemical rays".

These behaved to visible violet light rays, but were beyond them in the spectrum. They were renamed ultraviolet radiation. Electromagnetic radiation was first linked to electromagnetism in 1845, when Michael Faraday noticed that the polarization of light traveling through a transparent material responded to a magnetic field. During the 1860s James Maxwell developed four partial differential equations for the electromagnetic field. Two of these equations predicted the behavior of waves in the field. Analyzing the speed of these theoretical waves, Maxwell realized that they must travel at a speed, about the known speed of light; this startling coincidence in value led Maxwell to make the inference that light itself is a type of electromagnetic wave. Maxwell's equations predicted an infinite number of frequencies of electromagnetic waves, all traveling at the speed of light; this was the first indication of the existence of the entire electromagnetic spectrum. Maxwell's predicted waves included waves at low frequencies compared to infrared, which in theory might be created by oscillating charges in an ordinary electrical circuit of a certain type.

Attempting to prove Maxwell's equations and detect such low frequency electromagnetic radiation, in 1886 the physicist Heinrich Hertz built an apparatus to generate and detect what are now called radio waves. Hertz was able to infer that they traveled at the speed of light. Hertz demonstrated that the new radiation could be both reflected and refracted by various dielectric media, in the same manner as light. For example, Hertz was able to focus the waves using a lens made of tree resin. In a experiment, Hertz produced and measured the properties of microwaves; these new types of waves paved the way for inventions such as the radio. In 1895 Wilhelm Röntgen noticed a new type of radiation emitted during an experiment with an evacuated tube subjected to a high voltage, he called these radiations x-rays and found that they were able to travel through parts of the human body but were reflected or stopped by denser matter such as bones. Before long, many uses were found for them in the field of medicine.

The last portion of the electromagnetic spectrum was filled in with the discovery of gamma rays. In 1900 Paul Villard was studying the radioactive emissions of radium when he identified a new type of radiation that he first thought consisted of particles similar to known alpha and beta particles, but with the power of being far more penetrating than either. However, in 1910, British physicist William Henry Bragg demonstrated that gamma rays are electromagnetic radiation, not particles, in 1914, Ernest Rutherford and Edward Andrade measured their wavelengths, found that gamma rays were similar to X-rays, but with shorter wavelengths and higher frequencies. Electromagnetic waves are described by any of the following three physical properties: the frequency f, wavelength λ, or photon energy E. Frequencies observed in astronomy range from 2.4×1023 Hz down to the local plasma

Hokovirus

Hokovirus is a genus of giant double-stranded DNA-containing viruses. This genus was detected during the analysis of metagenome samples of bottom sediments of reservoirs at the wastewater treatment plant in Klosterneuburg, Austria. New Klosneuvirus and Indivirus genera were described together with Hokovirus, building up a putative virus subfamily Klosneuvirinae with KNV as type genus. Hokovirus has a large genome of 1.33 million base pairs. This is the third largest genome among known Klosneuviruses after Catovirus. GC content is 21.4 % Classification of metagenome, made by analyzing 18S rRNA indicate that their hosts are relate to the simple Cercozoa. Phylogenetic tree topology of Mimiviridae is still under discussion; some authors like to put Klosneuviruses together with Cafeteria roenbergensis virus and Bodo saltans virus into a tentative subfamily called Aquavirinae. Another proposal is to put therse all together with Mimiviruses into a subfamily Megavirinae. Nucleocytoplasmic large DNA viruses Girus Mimiviridae Mitch Leslie: Giant viruses found in Austrian sewage fuel debate over potential fourth domain of life.

In: Science. 5. April 2017, doi:10.1126/science.aal1005

Vicente Paulo da Silva

Vicente Paulo da Silva more known as Vicentinho is a Brazilian politician as well as a syndicalist and trade union president. Although born in Rio Grande do Norte, he has spent his political career representing São Paulo, having served as federal deputy representative since 2003. Vicentinho is the son of Maria Jeronimo da Silva. Prior to entering politics he was the head of syndicalist organization in São Paulo and was the president for 36 years of a trade union called "Central Única dos Trabalhadores" that campaigned for wage equality. Vicentinho voted against the impeachment motion of then-president Dilma Rousseff and political reformation, he would vote in favor of opening a similar corruption investigation against Rousseff's successor Michel Temer, voted against the 2017 Brazilian labor reforms. Vicentinho was investigated during Operation Car Wash for taking R$30,000 in bribes from Odebrecht

Rossia pacifica

Rossia pacifica known as the stubby squid, is in the order of Bobtail squid that native to the northern Pacific Ocean. This species has eight arms and two retractable limbs like a squid, while remaining closer to the ocean bottom similar to the octopus. While the common name may suggest this species is a squid, they are more related to cuttlefish. Seen in winter on sandy slopes away from strong currents in moderately shallow water, it moves in summer to deeper water where it breeds; the female cements the egg capsules under a stone or in some other concealed location, both male and female die soon after breeding. Two subspecies are recognised: - Rossia pacifica diegensis Berry, 1911 Rossia pacifica pacifica Berry, 1911 The stubby squid is a small species growing to a maximum mantle length of about 5 cm and a total length of 11 cm, with females being larger than males; the head bears a pair of retractable tentacles and two large eyes. The first pair of arms is shorter than the third pair the longest.

The arms are circular in cross-section and each bears up to four rows of suckers on the middle section and two rows elsewhere. The tentacles have club-shaped tips with suckers and retract into pits in the head, they can be as long as the body when extended. The mantle is flattened dorso-ventrally and rounded at the back, it does not contain the cuttlefish bone typical of cuttlefish in the family Sepiidae. There are two large semi-circular fins with wide bases on either side of the mantle; the upper surface of this epic squid is a reddish-brown colour with a scattering of small brown or yellowish spots, but can change to greyish-green when the animal is startled. The stubby squid is native to the northern Pacific Ocean, its range extends from Korea and the Bering Sea to the western coast of North America, as far south as California. Its depth range is 20 to 1,350 m. Monterey Bay Aquarium Research Institute researchers reported a sighting of a stubby squid deeper in the ocean. In Puget Sound it is seen in winter in regions of sloping muddy sand away from strong currents at less than 300 m but moves into deeper water in the summer.

When found in coastal regions it has been reported in the sub-tidal zone and has been found at night swimming at shore in the intertidal zone. It has been found to be able to live and survive in polluted urban west coast bay areas of the United States; the stubby squid rests on the seabed and moves around, either by movement of its fins or by expelling a jet of water from its body cavity through a movable funnel just below the head. When disturbed, it can leave behind a thick blob of black ink, it spends the day semi-buried in soft sediment on the seabed. To submerge itself, it directs a stream of water at the sand to create a funnel-shaped depression it settles in the hollow and scoops sand over itself with a pair of arms, just leaving the eyes exposed. While immobile, it folds its arms under its head; the stubby squid has a hardened beak it uses to eat, its mouth is centered on the body and all tentacles connect at this point as well. It has adapted to a carnivorous diet by using a raptorial style of hunting.

The squid will use its specialized eyes to locate the prey and attack with its tentacles. More than 80% of their diet is shrimps but they consume small crabs, mysida and other cephalopods. Breeding takes place in late autumn in deep water; the male will transfer the spermataphores into the female's mantle cavity with his hectocotylus, first left arm. The mature male and female die soon after breeding; the average female will deposit between twenty-five and fifty eggs in clusters, attaching them to the underside of stones, clams or seaweeds. The capsules are creamy-white and durable they take four to nine months to hatch and receive no additional care; the egg itself, is contained in a larger capsule. The juveniles that emerge are miniature versions of the adults

LNER Class J38

The London and North Eastern Railway Class J38 was a class of steam locomotive designed for freight transport. They were designed by Nigel Gresley and introduced in 1926. A total of 35 were built and they were used in Scotland. All passed into British Railways ownership in 1948 and they were numbered 65900-65934; the J39 was a development, exchanging the J38's 4 ft 8 in driving wheels with larger 5 ft 2 in, 289 J39s being built. Some of the J38s were rebuilt with J39 boilers. BR Power classification, 6F Locomotive weight, 58 long tons 19 cwt Tender weight, 44 long tons 4 cwt Boiler pressure, 180 psi Superheater, Yes Cylinders, 20 in × 26 in Driving wheel diameter, 4 ft 8 in Tractive effort, 28,415 lbf Valve gear, Stephenson piston valves All J38s were withdrawn between 1962 and 1967, with the last two in service being No. 65901 and No. 65929, with none surviving into preservation and not falling to the cutter's torch. The Gresley J38 0-6-0 Locomotives LNER encyclopedia Class Details RailUK

Friedrich Voltz

Johann Friedrich Voltz was a German landscape and animal painter of the Munich School. Voltz received his first art instruction from his father, Johann Michael Voltz, a painter and engraver, he began as an etcher and, in 1834, went to Munich to study at the Academy of Fine Arts. However, he derived more inspiration from nature and his studies of the old Dutch Masters at the Alte Pinakothek, he was influenced by Albrecht Adam and his friends, Carl Spitzweg and Eduard Schleich. Sometimes, he would paint the cows in Schleich's landscapes, he continued to paint Bavarian landscapes through the 1830s. While visiting the Netherlands in 1841, he saw Der Junge Stier, a painting by Paulus Potter and, from there on, devoted himself to animal painting. During a tour of Belgium and the Netherlands in 1846, he absorbed the style of the Dutch Stimmungsmalern, he experimented with lighting. In his paintings, the animals are treated as still-lifes, with the dramatic effects created by the play of light, he died rather unexpectedly when an innocuous foot ailment turned into a serious illness.

Voltz is considered one of the great German animal painters along with Anton Braith. His paintings are on display among many others. List of German painters Media related to Friedrich Voltz at Wikimedia Commons Literature by and about Friedrich Voltz in the German National Library catalogue Life and Work of Johann Friedrich Voltz