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Karyotype

Karyotyping is the process by which photographs of chromosomes are taken in order to determine the chromosome complement of an individual, including the number of chromosomes and any abnormalities. The term is used for the complete set of chromosomes in a species or in an individual organism and for a test that detects this complement or measures the number. Karyotypes describe the chromosome count of an organism and what these chromosomes look like under a light microscope. Attention is paid to their length, the position of the centromeres, banding pattern, any differences between the sex chromosomes, any other physical characteristics; the preparation and study of karyotypes is part of cytogenetics. The study of whole sets of chromosomes is sometimes known as karyology; the chromosomes are depicted in a standard format known as a karyogram or idiogram: in pairs, ordered by size and position of centromere for chromosomes of the same size. The basic number of chromosomes in the somatic cells of an individual or a species is called the somatic number and is designated 2n.

In the germ-line the chromosome number is n.p28 Thus, in humans 2n = 46. So, in normal diploid organisms, autosomal chromosomes are present in two copies. There may, or may not, be sex chromosomes. Polyploid cells haploid cells have single copies. Karyotypes can be used for many purposes. Chromosomes were first observed in plant cells by Carl Wilhelm von Nägeli in 1842, their behavior in animal cells was described by Walther Flemming, the discoverer of mitosis, in 1882. The name was coined by another German anatomist, Heinrich von Waldeyer in 1888, it is New Latin from Ancient Greek κάρυον karyon, "kernel", "seed", or "nucleus", τύπος typos, "general form") The next stage took place after the development of genetics in the early 20th century, when it was appreciated that chromosomes were the carrier of genes. Lev Delaunay in 1922 seems to have been the first person to define the karyotype as the phenotypic appearance of the somatic chromosomes, in contrast to their genic contents; the subsequent history of the concept can be followed in the works of C. D. Darlington and Michael JD White.

Investigation into the human karyotype took many years to settle the most basic question: how many chromosomes does a normal diploid human cell contain? In 1912, Hans von Winiwarter reported 47 chromosomes in spermatogonia and 48 in oogonia, concluding an XX/XO sex determination mechanism. Painter in 1922 was not certain whether the diploid of humans was 46 or 48, at first favoring 46, but revised his opinion from 46 to 48, he insisted on humans having an XX/XY system. Considering the techniques of the time, these results were remarkable. Joe Hin Tjio working in Albert Levan's lab found the chromosome count to be 46 using new techniques available at the time: Using cells in tissue culture Pretreating cells in a hypotonic solution, which swells them and spreads the chromosomes Arresting mitosis in metaphase by a solution of colchicine Squashing the preparation on the slide forcing the chromosomes into a single plane Cutting up a photomicrograph and arranging the result into an indisputable karyogram.

The work took place in 1955, was published in 1956. The karyotype of humans includes only 46 chromosomes; the great apes have 48 chromosomes. Human chromosome 2 is now known to be a result of an end-to-end fusion of two ancestral ape chromosomes; the study of karyotypes is made possible by staining. A suitable dye, such as Giemsa, is applied after cells have been arrested during cell division by a solution of colchicine in metaphase or prometaphase when most condensed. In order for the Giemsa stain to adhere all chromosomal proteins must be digested and removed. For humans, white blood cells are used most because they are induced to divide and grow in tissue culture. Sometimes observations may be made on non-dividing cells; the sex of an unborn fetus can be determined by observation of interphase cells. Six different characteristics of karyotypes are observed and compared: Differences in absolute sizes of chromosomes. Chromosomes can vary in absolute size by as much as twenty-fold between genera of the same family.

For example, the legumes Lotus tenuis and Vicia faba each have six pairs of chromosomes, yet V. faba chromosomes are many times larger. These differences reflect different amounts of DNA duplication. Differences in the position of centromeres; these differences came about through translocations. Differences in relative size of chromosomes; these differences arose from segmental interchange of unequal lengths. Differences in basic number of chromosomes; these differences could have resulted from successive unequal translocations which removed all the essential genetic material from a chromosome, permitting its loss without penalty to the organism or through fusion. Humans have one pair fewer chromosomes than the great apes. Human chromosome 2 appears to have resulted from the fusion of two ancestral chromosomes, many of the genes of those two original chromosomes have been translocated to other chromosomes. Differences in number and position of satellites. Satellites are small bodies attached to a chromosome by a thin thread.

Differences in degree and distribution of heterochromatic regions. Heterochromatin stains darker than euchromatin. Heterochromatin is packed tighter. Heterochromatin consists of

Pennsylvania Route 660

Pennsylvania Route 660 is a 24.1-mile-long state highway located in Tioga County in Pennsylvania. The western terminus is at the entrance of Leonard Harrison State Park in Shippen Township; the eastern terminus is at U. S. Route 15 and U. S. Route 15 Business in Richmond Township. Route 660 begins at the entrance to Leonard Harrison State Park in Shippen Township; the route proceeds eastward out of the park into Shippen Township, reaching an intersection with State Route 3004, where the southeast-bound right-of-way is taken over for Route 660. Route 660 makes a short dip into the community of Kennedy, where it turns eastward at an intersection with Wilson Street; the highway makes a long eastward stretch through the rural areas of Tioga County, paralleling Route 3004 for a distance to the south. After the intersection with Martin Road, Route 660 turns northward, intersecting with Route 3004's other terminus, where it turns east along the right-of-way. A short distance Route 660 enters Thumptown, a local community in Delmar Township.

There, the highway comes to an intersection with State Route 3006 and State Route 3007. Route 660 turns to the northeast on the right-of-way once held by State Route 3007 and crosses through Delmar Township's rural surroundings before entering the community of Dexter, where Route 660 turns eastward at an intersection with State Route 3029, which connects to Route 362 and Grand Canyon State Airport. Meanwhile, Route 660 crosses through Dexter and continues in a general eastward manner until reaching Morral Road, where it proceeds northeastward once again. At this stretch, some residences appear along the side of the road and soon Route 660 intersects with the western terminus of Route 362, east of the Grand Canyon State Airport in Delmar Township. Like before, Route 660 turns along the right-of-way used by Route 362, begins crossing through a more developed portion of Delmar Township. Passing to the north of Tioga Country Club, Route 660 gains the moniker of Pinecreek Road before entering the borough of Wellsboro.

In Wellsboro, Route 660 changes monikers to West Avenue, crossing through a dense portion of the center of the borough. After curving to the northeast once again at the intersection with Lincoln Street, the moniker changes to Main Street. After passing through more of the commercial district, Route 660 intersects with Route 287 in downtown Wellsboro; the two roads form a short concurrency before intersecting with U. S. Route 6. At this intersection, Route 287 proceeds on a concurrency west with U. S. Route 6, while Route 660 proceeds east on its concurrency with U. S. Route 6. After the intersection, U. S. Route 6 and Route 660 head eastward through a more residential portion of Wellsboro; the two highways continue eastward as East Avenue, before proceeding to leave Wellsboro for Charleston Township. After leaving Wellsboro for Charleston Township, the moniker switches to Grand Army of the Republic Highway, a name associated with U. S. Route 6 throughout the United States; the two roads immediately enters the hamlet of Pitts, which consists of a few residences and industries at the eastern edges of Wellsboro.

U. S. Route 6 and Route 660 leave Pitts and bend to the northeast through Charleston Township rural for most of the trip. Both roads pass to the southeast of Dart Settlement and begin a parallel with an old alignment of U. S. Route 6 through Charleston Township; the old alignment merges in with the newer one at a bend in the highway, which turns eastward for a small strip before turning northeastward once again. At the intersection with Charleston Road in the community of Whitneyville, Route 660 turns eastward from U. S. Route 6 as North Elk Run Road. For a distance, Route 660 has a parallel with U. S. Route 6 through fields. Soon after, both roads cross into Richmond Township; the surroundings on Route 660 remain rural while the parallel begins to break at the intersection with Spencer Road, where the highway turns to the southeast. After the intersection with Mack Road, Route 660 enters some dense woods east of the community of Covington. A short distance after leaving the woods, Route 660 enters Covington.

In Covington, Route 660 intersects with the old alignment of U. S. Route 15 at North Williamson Road. PA 660 turns left onto the old US 15 alignment and passes through a mix of fields and residences as it reenters Richmond Township; this time, entering the community of Canoe Camp, the road crosses the former Erie Railroad Tioga Division right-of-way, soon enters an interchange with U. S. Route 15; this serves as the eastern terminus of Route 660, while the U. S. Route 15 Business continues northward into Mansfield; the entire route is in Tioga County. U. S. Roads portal Pennsylvania portal Kitsko, Jeffrey J.. "PA 660". Pennsylvania Highways. Pp. 651–700. Retrieved December 21, 2011

Fred Iltis

Fred Iltis was an American entomologist. His research focused on the biosystematics and life cycle of mosquitoes, he was born Wilfred Gregor Iltis to Anni and Hugo Iltis, a botanist and geneticist, a life sciences teacher at the German-language gymnasium of Brünn. His father was the first biographer of Gregor Mendel and a vocal opponent of Nazi "racial science". In the fall of 1938, the Iltis family was granted visas to enter the United States thanks to the intercession of the Emergency Committee in Aid of Displaced Foreign Scholars, along with affidavits of endorsement from Albert Einstein and Franz Boas. In January 1939, when Hitler's military was preparing the invasion of Czechoslovakia, fifteen-year-old Wilfred escaped with his mother and his younger brother Hugh on a harrowing train ride that traversed Nazi Germany to France. During a midnight stop at the Stuttgart station, Gestapo officers combed the train, removing ten passengers. In Cherbourg, they were joined by Hugo Iltis and boarded the passenger ship RMS Aquitania for the Atlantic crossing.

They settled in Fredericksburg, where the senior Hugo Iltis was soon appointed to a professorship in biology at Mary Washington College. Iltis began his undergraduate studies in 1941 at George Washington University but after one semester transferred to Western Kentucky State Teachers College, pursuing a major in agriculture. During World War II, Fred Iltis served in the Army in the South Pacific. In 1948, he married a graphic artist and scientific illustrator, he went on to earn a Ph. D. in entomology at University of California, Davis. Iltis worked at Harvard in 1967-1968 as a research fellow in Tropical Public Health for the Harvard School of Public Health. After settling in San Jose, California, in the 1960s, Iltis taught in the Biology Department at San José State University. Iltis was a skilled photographer, he developed and printed photos in a basement darkroom, using the slow and complicated archival process system yielding prints that last many decades. In his journeys south of the border, Iltis portrayed the life of the Mexican Indians in Michoacán.

Many photos of his vast archive document the Civil rights movement of the 1960s, student protests against the Vietnam War, the struggle of the Chicano agricultural workers led by César Chávez and Dolores Huerta, as well as the strikes and boycott of American fruit companies. He met and befriended the renowned photojournalists Hansel Mieth and Otto Hagel, who had documented the Great Depression of the 1930s in Life magazine. From them Iltis learned that "a photo can express one’s ideas and ideals far better than a thousand words". Iltis, Wilfred Gregor. "Biosystematics of the Culex pipiens complex in Northern California, California, 1966." Ph. D. diss. University of California, Davis, 1977. Daniele Ravenna, Felix Humm, Fred Iltis. Biologist and Friend, Milano, DR&C Editore, 2009. ISBN 978-88-904465-0-4. Https://web.archive.org/web/20100610052203/http://entomology.ucdavis.edu/news/bugbytesspring09.pdf http://frediltis.blogspot.com/ http://frediltis.com/sn-english.htm Photo Collection at UC Berkeley

Eastern Distributor

The Eastern Distributor is a 6-kilometre long motorway in Sydney, New South Wales, Australia, 75.1% owned by toll road operator Transurban. Part of the M1, it links the Sydney central business district with the Airport; the centre-piece is a 1.7 km tunnel running from Woolloomooloo to Surry Hills. The motorway is tolled in one direction with the toll plazas at Woolloomooloo and at the William Street exit; as of February 2017, the toll for cars/motorbikes is $6.95 and $13.90 for other vehicles. The toll will be removed in 2048; this motorway is part of the 110-kilometre Sydney Orbital Network. For about half its length, it is in a trench inside South Dowling Street; the motorway provides a southbound exit for Lachlan Street/Dacey Avenue, a northbound exit for Cleveland Street, northbound entrance ramp from Cleveland Street and connections to William Street. There are connection to the Cross City Tunnel, giving motorists direct connections under the city to the Western Distributor. There are northbound/southbound entry/exits to Moore Park Road and Anzac Parade.

Southbound motorists were found to be entering the Eastern Distributor from the Cross City Tunnel access point and attempting to cross three lanes for the Anzac Parade off-ramp. Permanent traffic obstacles are now in place to prevent this and users are now referred to the Lachlan Street/Dacey Avenue exit instead; the need for an Eastern Distributor was first talked about in 1951. It was not until the election of the state Labor government in 1995, led by premier Bob Carr that the project was initiated. At 6 kilometres in length, the Eastern Distributor was built to link the Sydney central business district with Sydney Airport via the existing Southern Cross Drive, it was designed to reduce the time to travel from the city to the airport. Construction involved 5,000 workers and was undertaken by Leighton Contractors for Airport Motorway Limited. Built, the Eastern Distributor is privately owned and operated by Transurban, with state government planning and management during construction. At a cost of A$730 million, the motorway was opened on 19 December 1999, except for the William Street on and off ramps which were opened on 23 July 2000, just in time for the Sydney 2000 Summer Olympic Games.

The term of private ownership is 48 years after which the road will revert to government ownership on 23 July 2048. Two separate tunnel subcontractors began excavating the northbound tunnel in January 1996, working at either of the tunnel—that is, Surry Hills and Woolloomooloo. Seven roadheaders were utilised for the tunnel boring, with the rock ceiling reinforced with rock bolts and shotcrete. On 4 December 1998 the two teams were shaking hands in the middle–30 metres beneath Taylor Square. Actual construction started in August 1997 and by March 1999 all digging was complete, after 400,000 cubic metres of soil Sydney Hawkesbury Sandstone was removed–equal to 40,000 truckloads; the project's centrepiece is the 1.7-kilometre piggyback tunnel under one of Australia's most densely populated urban areas, necessitated due to the requirement of three lanes in each direction within the existing roadway corridor. The unique double-deck, three lanes per direction design comprises a large, single tunnel excavation.

At mid-height through the excavation, a precast concrete ledge forms the base of the northbound tunnel, with the southbound tunnel slotting below. As a result, only one tunnel roof was created with the lower southbound carriageway built in a slot. According to the Australasian Tunnelling Society, no records are available of any piggyback tunnel where the upper carriageway has been carried on prestressed concrete planks resting on sidewall ledges. In the main tunnel there is a central length of 0.5 kilometres where the span is greater than 17 metres, of note, there is no record of any road tunnel with spans greater than this where permanent roof support comprises rockbolts and shotcrete only and with vertical unsupported sidewalls of rock. The tunnel's claim to fame at the time it was built was that at 24.5 metres across at its widest point, it was the widest tunnel in the world. This point occurs. At 14 metres, the tunnel is notably large from the ceiling to the floor; the tunnels of the Eastern Distributor are equipped with lighting, drainage, CCTV surveillance, fire fighting and emergency control systems.

This is a history of the toll charges: Freeways in Australia Freeways in Sydney Official Site Roam Express Eastern Distributor Toll prices Web Cam Eastern Distributor on Google Maps

Charles Daudelin

Charles Daudelin, was a French Canadian sculptor and painter, a major Quebec artist. Born in Granby, Quebec, he became a pioneer in integrating art into public space, he created many public artworks, including: Polypède, McGill University, Montreal Allegrocube, Palais de justice de Montréal. Charles Daudelin died in Quebec, his last work, Le Passage du 2 avril, is named for the date of his death and installed in front of Kirkland City Hall. A postage stamp depicting Daudelin's work Embâcle was issued by Canada Post on June 10, 2002. Prix Paul-Émile-Borduas, Government of Quebec, 1985 Member, Ordre national du Québec, 1998 Royal Canadian Academy of Arts "Charles Daudelin". MONTREAL BY METRO. Retrieved 2008-03-21

Huey Long (Keck)

Huey Long is a 1941 bronze sculpture of Huey Long by Charles Keck, installed in the United States Capitol, in Washington, D. C. as part of the National Statuary Hall Collection. It is one of two statues donated by the state of Louisiana; the statue was accepted in the collection by Senator Allen Ellender on April 25, 1941. At that time Ellender said, “He was a doer of things for the benefit of the masses. Marked him for death.”Long, a popular populist nicknamed “The Kingfish” was first Governor and Senator from Louisiana and was assassinated in Baton Rouge on September 10, 1935A similar statue, without the raiser right arm, of Long by Keck was unveiled in 1940 on the grounds of the Louisiana State Capitol. 1941 in art Media related to Huey Long by Charles Keck at Wikimedia Commons