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Semisynthesis

Semisynthesis or partial chemical synthesis is a type of chemical synthesis that uses chemical compounds isolated from natural sources as the starting materials to produce other novel compounds with distinct chemical and medicinal properties. These novel compounds are high molecular weight or have complex molecular structure, more so than those produced by total synthesis from simple starting materials. Semisynthesis is a means of preparing many medicines more cheaply than if by total synthesis, because fewer chemical steps are necessary. Drugs derived from natural sources are produced by isolation from the natural source, or, as described here, by semisynthesis from such an isolated agent. From the viewpoint of chemical synthesis, living organisms are remarkable chemical factories, capable of producing structurally complex chemical compounds with ease by biosynthesis. In contrast, engineered chemical synthesis is simpler, with a lower chemical diversity in each reaction, than the diverse biosynthesis pathways that are crucial to life.

As a result, certain functional groups are much easier to prepare via engineered synthesis than others – for example, acetylation – where certain biosynthetic pathways can generate groups and structures with minimal economic input that would be prohibitive via total synthesis. Plants, animals and bacteria are all used as sources for these tricky precursor molecules, including the use of bioreactors at the meeting point between engineered and biological chemical synthesis. Semisynthesis, when used in drug discovery, aims to retain the sought-after medicinal activity while altering other molecule characteristics – for instance, those affecting its adverse events or its oral bioavailability – in a few chemical steps. In this regard, semisynthesis stands in contrast with the approach of total synthesis, where the aim is to arrive at a target molecule beginning with low-molecular-weight, inexpensive starting materials – petrochemicals or minerals. While there is no hard-and-fast division between total synthesis and semisynthesis – rather differing in the degree of engineered synthesis used – in practice many commodity precursor molecules with complex or fragile functional groups are much cheaper to extract from an organism than to prepare from simple precursors only.

Hence, methods of semisynthesis are applied when a needed precursor molecule is too structurally complex, too costly, or too difficult to produce by total synthesis. Examples of practical application of the use of semisynthesis include in the groundbreaking historic case of the isolation of the antibiotic chlortetracycline, the semisyntheses of the further novel antibiotics tetracycline and tigecycline. Further examples of semisynthesis include the early commercial production of anti-cancer agent paclitaxel from 10-deacetylbaccatin isolated from the needles of Taxus baccata, the preparation of LSD from ergotamine isolated from fungal cultures of ergot, the semisynthesis of the antimalarial drug artemether from occurring artemisinin; as the field of synthetic chemistry advances, certain transformations become cheaper or easier, the economics of a semisynthetic route may become less favorable. Chemurgy Drug discovery Drug development Production of cephalopsporins from 7-ACA Production of penicillins from 6-APA Production of steroids from 16-DPA

American yellow warbler

The yellow warbler is a New World warbler species. Warblers are the most widespread species in the diverse genus Setophaga, breeding in the whole of North America and down to northern South America; the genus name Setophaga is from Ancient Greek ses, "moth", phagos, "eating", the specific petechia is from Italian petecchia, a small red spot on the skin. The American yellow warbler is sometimes colloquially called the "summer yellowbird". Other than in male breeding plumage and body size, all warbler subspecies are similar. Winter and immature birds all have greenish-yellow uppersides and are a duller yellow below. Young males soon acquire breast and, where appropriate, head coloration. Females are somewhat duller, most notably on the head. In all, the remiges and rectrices are blackish olive with yellow edges, sometimes appearing as an indistinct wing-band on the former; the eyes and the short thin beak are dark, while the feet are darker olive-buff. The 35 subspecies of D. petechia can be divided into three main groups according to the males' head color in the breeding season.

Each of these groups is sometimes considered a separate species, or the aestiva group is considered a species different from D. petechia. Depending on subspecies, the American yellow warbler may be between 10 and 18 cm long, with a wingspan from 16 to 22 cm, they weigh 7–25 g, varying between subspecies and whether on migration or not, globally averaging about 16 g but only 9–10 g in most breeding adults of the United States populations. Among standard measurements throughout the subspecies, the wing chord is 5.5 to 7 cm, the tail is 3.9 to 5.6 cm, the bill is 0.8 to 1.3 cm and the tarsus is 1.7 to 2.2 cm. The summer males of this species are the yellowest warblers wherever they occur, they are greenish-golden above. There are a few wide, somewhat washed-out rusty-red streaks on the breast and flanks; these markings are the reason for the scientific name petechia, which translates to "liver spotted". The subspecies in this group vary in brightness and size according to Bergmann's and Gloger's Rule.

The golden warbler is resident in the mangrove swamps of the West Indies. Local seasonal migrations may occur. On the Cayman Islands for example, D. p. eoa was found to be "decidedly scarce" on Grand Cayman and absent from Cayman Brac in November 1979, while it had been a "very common" breeder in the group some 10 years before, not seen in the winters of 1972/1973. The Cuban golden warbler reached the Florida Keys where it was first noted in 1941, by the mid-20th century a breeding population was resident. Though individual birds may stray farther north, their distribution is restricted by the absence of mangrove habitat, they are smallish weighing about 10 g or less and sometimes as little as 6.5 g. The summer males differs from those of the yellow warbler in that they have a rufous crown, hood or mask; the races in this group vary in the hue of the head patch. The mangrove warbler tends to be larger than other yellow warbler subspecies groups, averaging 12.5 cm in length and 11 g in weight. It is resident in the mangrove swamps of northern South America.

The summer males differ from those of the yellow warbler in having a rufous crown. The races in this group vary in the extent and hue of the hood, overlapping extensively with the golden warbler group in this character; the American yellow warbler breeds in the whole of temperate North America as far south as central Mexico in open wet, woods or shrub. It is migratory, wintering in South America, they are rare vagrants to western Europe. The song is a musical strophe that can be rendered sweet sweet sweet, I'm so sweet, although it varies between populations; the call is a soft or harder ship. This is frequently given by females after a male has finished his song. In territorial defence, they give hissing calls, while seet seems to be a kind of specialized cowbird alert. Other calls are given in communication between pair-members, neighbors, or by young begging for food; these birds communicate with postures and with touch. American yellow warblers breed in most of North America from the tundra southwards, except for the far Southwest and the Gulf of Mexico coast.

American yellow warblers winter to the south of their breeding range, from southern California to the Amazon region and Peru. The mangrove and golden warblers occur to the northern reaches of the Andes. American yellow warblers arrive in their breeding range in late spring – about April/May – and move to winter quarters again starting as early as July, as soon as the young are fledged. Most, stay a bit longer. At least in northern Ohio, yellow warblers do not linger; the breeding habitat of American yellow warblers is riparian or otherwise moist land with ample growth of s

Pietro Foresti

Pietro Foresti is an Italian music producer and manager. His production and engineering credits include work in Los Angeles, with numerous major label artists, including Tracii Guns, Scott Russo, Marvin Etzioni, his production and engineering colleagues on more than four dozen albums have included Sylvia Massy Shivy, Michael C. Ross, Joe Gastwirt and Kaos India. Foresti is producer and manager for his wife, Italian pop superstar Valeria Rossi, whose hit “Tre Parole” climbed to number one in both the Italian and Spanish charts and was awarded a top prize at the 2002 Italian Music Awards. With Rossi, Foresti created; as producer, Foresti was nominated for two music awards in 2010 from the Union Fonografica Independiente for the album The Promise by the band Warrior Poet, featuring Scott Russo. The album was nominated for “Best Rock Album” and "Best Alternative Rock Album."He has been a judge on several Italian television talent shows, including “Diventerò Una Star - e Una Persona Migliore,” “La Spada d'Oro”, Concorso Canoro's “Note Azzurre”, "In…canto a Morciano.”Foresti holds a university degree in musicology from the University of Cremona, School of Musical Philology and Paleography, master's degree in music therapy from the Art-Therapy School in Lecco.

Foresti is a recognized performance and mental coach, offering assistance to musicians and performers with mental preparation and enhanced focus. He lives in Monza

Dragon Park Ha Long

Dragon Park is the largest theme park in Southeast Asia located in Ha Long, Quang Ninh, Vietnam. It opened on January 25, 2017; the amusement park is part of a large resort complex known as Sun World Halong Complex that includes an aerial tramway called the Queen Cable Car, Sun Wheel — a large observation wheel, as well as gardens, restaurants, a shopping district and a family entertainment center with arcade games. The Typhoon water park opened in April 2017 The park was designed in 2015 by International Theme Park Services, Inc. in collaboration with Wyatt Design Group and Hetzel Design, both based in California. Dragon Park, including the SunWorld HaLong resort, is owned by Sun Group, a Vietnamese investment group, established in 2007 and specializes in hospitality, real estate development and construction. In addition to three roller coasters, the park has 29 rides including Rhino Sling. Coming from France, the Topple Tower Tang'Or moved to Dragon Park and is named Crazy Crane

Whispering Pines, Gila County, Arizona

Whispering Pines is a census-designated place in Gila County, United States. It is one of two locations in Arizona with this name, the other being a populated place in Greenlee County; the population was 148 at the 2010 United States Census. Whispering Pines is located in northern Gila County in the upper valley of the East Verde River, between Washington Park to the north and Beaver Valley to the south, it is 12 miles north of Payson. According to the United States Census Bureau, the Whispering Pines CDP has a total area of 0.43 square miles, all of it land

Oleksandr Obolonchyk

Oleksandr Obolonchyk is a Ukrainian luger. He participated at the 2018 Winter Olympics. Obolonczyk started his international career in 2009 competing in singles, he debuted finishing 60th in Igls, his single race in World Cup that year. In season 2010-11 he participated in 6 out of 9 races and achieved his personal best - 27th in Königssee. Two more seasons he competed in singles but he switched to doubles. Roman Zakharkiv is since his partner. Obolonchyk competed at the 2014 Winter Olympics for Ukraine. In the doubles he competed with Roman Zakharkiv, he was a part of the Ukrainian relay team, which finished 11th. He participated in doubles and relay competitions at three World Championships without any great success; as of January 2018, his best finish is 13th place in Latvia, in 2016-17 season. On December 27, 2017, Obolonchyk qualified for 2018 Winter Olympics. At that Games he competed together with Roman Zakharkiv and finished 20th in doubles competition and 13th in team relay. Obolonchyk graduated from Lviv State University of Physical Culture.

Now he studies at Ternopil State Economics University. His hobbies are computer and music