Low-carbohydrate diets or carbohydrate-restricted diets are diets that restrict carbohydrate consumption. Foods high in carbohydrates are limited or replaced with foods containing a higher percentage of fats and moderate protein and other foods low in carbohydrates, although other vegetables and fruits are allowed. There is a lack of standardization of how much carbohydrate low-carbohydrate diets must have, this has complicated research. One definition, from the American Academy of Family Physicians, specifies low-carbohydrate diets as having less than 20% carbohydrate content. Low-carbohydrate diets are associated with increased mortality, they can miss out on the health benefits afforded by high-quality carbohydrate such as is found in legumes including grain legumes or pulses, fruit and vegetables. Disadvantages of the diet might include halitosis and constipation, in general the potential adverse effects of the diet are under-researched for more serious possible risks such as for bone health and cancer incidence.
Carbohydrate-restricted diets can be as effective, or marginally more effective, than low-fat diets in helping achieve weight loss in the short term. In the long term, effective weight maintenance depends on calorie restriction, not the ratio of macronutrients in a diet; the hypothesis proposed by diet advocates that carbohydrate causes undue fat accumulation via the medium of insulin, that low-carbohydrate diets have a "metabolic advantage", has been falsified by experiment. It is not clear. Carbohydrate-restricted diets are no more effective than a conventional healthy diet in preventing the onset of type 2 diabetes, but for people with type 2 diabetes they are a viable option for losing weight or helping with glycemic control. There is little evidence; the American Diabetes Association recommends that people with diabetes should adopt a healthy diet, rather than a diet focused on carbohydrate or other macronutrients. An extreme form of low-carbohydrate diet – the ketogenic diet – is established as a medical diet for treating epilepsy.
Through celebrity endorsement it has become a popular weight-loss fad diet, but there is no evidence of any distinctive benefit for this purpose, it had a number of side effects. The British Dietetic Association named it one of the "top 5 worst celeb diets to avoid in 2018"; the macronutrient ratios of low-carbohydrate diets are not standardized. As of 2018 the conflicting definitions of "low-carbohydrate" diets have complicated research into the subject; the American Academy of Family Physicians defines low-carbohydrate diets as diets that restrict carbohydrate intake to 20 to 60 grams per day less than 20% of caloric intake. A 2016 review of low-carbohydrate diets classified diets with 50g of carbohydrate per day as "very low" and diets with 40% of calories from carbohydrates as "mild" low-carbohydrate diets. In a 2015 review Richard D. Feinman and colleagues proposed that a low carbohydrate diet had less that 10% caloric intake from carbohydrate, a low carbohydrate diet less than 26%, a medium carbohydrate diet less than 45%, a high carbohydrate diet more than 45%.
Both high- and low-carbohydrate diets are associated with increased mortality. The optimal proportion of carbohydrate in a diet for health is thought to be 50-55%. There is evidence that the quality, rather than the quantity, of carbohydrate in a diet is important for health, that high-fiber slow-digesting carbohydrate-rich foods are healthful while highly-refined and sugary foods are less so. People choosing diet for health conditions should have their diet tailored to their individual requirements. For people with metabolic conditions, in general a diet with 40-50% high-quality carbohydrate is compatible with what is scientifically established to be a healthy diet; some fruits may contain high concentrations of sugar, most are water and not calorie-dense. Thus, in absolute terms sweet fruits and berries do not represent a significant source of carbohydrates in their natural form, typically contain a good deal of fiber which attenuates the absorption of sugar in the gut. Most vegetables are low- or moderate-carbohydrate foods.
Some vegetables, such as potatoes, carrots and rice are high in starch. Most low-carbohydrate diet plans accommodate vegetables such as broccoli, kale, cucumbers, cauliflower and most green-leafy vegetables. In 2004, the Canadian government ruled that foods sold in Canada could not be marketed with reduced or eliminated carbohydrate content as a selling point, because reduced carbohydrate content was not determined to be a health benefit; the government ruled that existing "low carb" and "no carb" packaging would have to be phased out by 2006. The National Academy of Medicine recommends a minimum intake of 130 g of carbohydrate per day; the FAO and WHO recommend that the majority of dietary energy come from carbohydrates. Low-carbohydrate diets are not an option recommended in the 2015-2020 edition of Dietary Guidelines for Americans, which instead recommends a low fat diet. Carbohydrate has been wrongly accused of being a uniquely "fattening" macronutrient, misleading many dieters into compro
Lady Franklin Bay Expedition
The 1881–1884 Lady Franklin Bay Expedition into the Canadian Arctic was led by Lt. Adolphus Greely and was promoted by the United States Army Signal Corps, its purpose was to establish a meteorological-observation station as part of the First International Polar Year, to collect astronomical and magnetic data. During the expedition, two members of the crew reached a new "Farthest North" record, but of the original twenty-five men only seven survived to return to the United States; the expedition was under the auspices of the Signal Corps at a time when the Corps' Chief Disbursements Officer, Henry W. Howgate, was arrested for embezzlement. However, that did not deter the execution of the voyage; the expedition was led by Lt. Adolphus Greely of the Fifth United States Cavalry, with astronomer Edward Israel and photographer George W. Rice among the crew of 21 officers and men, they sailed on the ship Proteus and reached St. John's, Newfoundland, in early July 1881. At Godhavn, they picked up two Inuit dogsled drivers, as well as physician Dr. Octave Pavy and Mr. Clay who had continued scientific studies instead of returning on Florence with the remainder of the 1880 Howgate Expedition.
Proteus arrived without problems at Lady Franklin Bay by August 11, dropped off men and provisions, left. In the following months, Lt. James Booth Lockwood and Sgt. David Legge Brainard achieved a new "farthest north" record at 83°24′N 40°46′W, off the north coast of Greenland. Unbeknownst to Greely, the summer had been extraordinarily warm, which led to an underestimation of the difficulties which their relief expeditions would face in reaching Lady Franklin Bay in subsequent years. By summer of 1882, the men were expecting a supply ship from the south. Neptune, laden with relief supplies, set out in July 1882 but, cut off by ice and weather, Capt. Beebe was forced to turn around prematurely. All he could do was leave some supplies at Smith Sound in August, the remaining provisions in Newfoundland, with plans for their delivery the following year. On July 20, Dr. Pavy's contract ended, Pavy announced that he would not renew it, but would continue to attend to the expedition's medical needs. Greely was incensed, ordered the doctor to turn over all his records and journals.
Pavy refused, Greely placed him under arrest. Pavy was not confined, however Greely claimed he intended to court-martial him when they returned to the United States. In 1883, new rescue attempts of Proteus, commanded by Lt. Ernest Garlington, Yantic, commanded by Cdr. Frank Wildes, USN, with Proteus being crushed by the ice. In summer 1883, in accordance with his instructions for the case of two consecutive relief expeditions not reaching Fort Conger, Greely decided to head South with his crew, it had been planned that the relief ships should depot supplies along the Nares Strait, around Cape Sabine and at Littleton Island, if they were unable to reach Fort Conger, which should have made for a comfortable wintering of Greely's men. But with Neptune not getting that far and Proteus sunk, in reality only a small emergency cache with 40 days worth of supplies had been laid at Cape Sabine by Proteus; when arriving there in October 1883, the season was too advanced for Greely to either try to brave the Baffin Bay to reach Greenland with his small boats, or to retire to Fort Conger, so he had to winter on the spot.
In 1884, Secretary of the Navy, William E. Chandler, was credited with planning the ensuing rescue effort, commanded by Cdr. Winfield Schley. While four vessels made it to Greely's camp on June 22, only seven men had survived the winter; the rest had succumbed to starvation and drowning, one man, Private Henry, had been shot on Greely's order for repeated theft of food rations. The surviving members of the expedition were received as heroes. A parade attended by thousands was held in New Hampshire, it was decided that each of the survivors was to be awarded a promotion in rank by the Army, although Greely refused. Rumors of cannibalism arose following the return of the bodies of those. On August 14, 1884, a few days after his funeral, the body of Lieutenant Frederick Kislingbury, second in command of the expedition, was exhumed and an autopsy was performed; the finding that flesh had been cut from the bones appeared to confirm the accusation. Lieutenant Greely denied any knowledge of cannibalism.
Hubank, Roger: North Sentinel Rock Press, 2014. ISBN 978-1940777443. A fictional account of the Lady Franklin Bay Expedition. Report By United States Board of Officers for relief of Lieut Greely and others 1883-1884 Annual Reports of the Secretary of the Navy Volume 1 The Greely Arctic Expedition as Narrated by Lieut. Greely 1884 The Rescue of Greely by Winfield Scott Schley 1885 Collection of the Lady Franklin Bay Expedition 1881-1884 held by The Explorer's Club
The Pampas are fertile South American lowlands that cover more than 750,000 km2 and include the Argentine provinces of Buenos Aires, La Pampa, Santa Fe, Entre Ríos and Córdoba. The vast plains are a natural region, interrupted only by the low Ventana and Tandil hills, near Bahía Blanca and Tandil, with a height of 1,300 m and 500 m, respectively; the climate is temperate, with precipitation of 600 to 1,200 mm, more or less evenly distributed through the year, making the soils appropriate for agriculture. The area is one of the distinct physiography provinces of the larger Paraná-Paraguay Plain division; the climate of the Pampas is temperate giving away to a more subtropical climate in the north and to a semiarid climate on the western fringes. Summer temperatures are more uniform than winter temperatures ranging from 28 to 33 °C during the day. However, most cities in the Pampas have high temperatures that push 38 °C, as occurs when a warm, northerly wind blows from southern Brazil. Autumn arrives in March, peaks in April and May.
In April, highs range from 20 to 25 °C and lows from 9 to 13 °C. The first frosts arrive in mid-April in the south, in late May or early June in the north. Winters are mild, but cold waves still occur. Normal temperatures range from 12 to 19 °C during the day, from 1 to 6 °C at night. With strong northerly winds, days of over 25 °C can be recorded everywhere, during cold waves, high temperatures can be only 6 °C. Frost occurs everywhere in the Pampas, but it is much more frequent in the southwest than around the Parana and Uruguay Rivers. Temperatures under −5 °C can occur everywhere, but values of −10 °C or lower are confined to the south and west. Snow never falls in the northernmost third and is rare and light elsewhere, except for exceptional events in which depths have reached 30 cm. Springs are variable. Violent storms are more common as well as wide temperature variations: days of 35 °C can give way to nights of under 5 °C or frost, all within only a few days. Precipitation ranges from 1,200 mm in the northeast, to about 500 mm in the southern and western edges.
In the west, it is seasonal, with some places recording averages of 120 mm monthly in the summer, only 20 millimetres monthly in the winter. The eastern areas have small peaks in the fall and in the spring, with rainy summers and winters that are only drier. However, where summer rain falls as short, heavy storms, winter rain falls as cold drizzle and so the amount of rainy days is constant. Intense thunderstorms are common in the spring and summer, it has among the most frequent lightning and highest convective cloud tops in the world; the severe thunderstorms produce intense hailstorms, both floods and flash floods, as well as the most active tornado region outside the central and southeastern US. Herbivores of the pampas are the pampas deer, gray brocket, dwarf mara, plains viscacha, Brazilian guinea pig, southern mountain cavy and coypu; the biggest predator of the region is the puma followed by the maned wolf, pampas fox, geoffroy's cat, lesser grison as well as the omnivorous white-eared opossum and molinas hog-nosed skunk.
Bird species of the pampas are ruddy-headed goose, pampas meadowlark, hudsonian godwit, maguari stork, white-faced ibis, white-winged coot, southern screamer, dot-winged crake, curve-billed reedhaunter, burrowing owl and the rhea. Frequent wildfires ensure that only small plants such as grasses flourish, trees are less common; the dominant vegetation types are grassy prairie and grass steppe in which numerous species of the grass genus Stipa are conspicuous. "Pampas grass" is an iconic species of the Pampas. Vegetation includes perennial grasses and herbs. Different strata of grasses occur because of gradients of water availability; the World Wildlife Fund divides the Pampas into three distinct ecoregions. The Uruguayan Savanna lies east of the Parana River, includes all of Uruguay, most of Entre Ríos and Corrientes provinces in Argentina, the southern portion of Brazil's state of Rio Grande do Sul; the Humid Pampas include eastern Buenos Aires Province, southern Entre Ríos Province. The Semiarid Pampas includes western Buenos Aires Province and adjacent portions of Santa Fe, Córdoba, La Pampa provinces.
The Pampas are bounded by the drier Argentine espinal grasslands, which form a semicircle around the north and south of the Humid Pampas. Winters are cool to mild and summers are warm and humid. Rainfall is uniform throughout the year, but is a little heavier during the summer. Annual rainfall is heaviest near the coast and decreases further inland. Rain during the late spring and summer arrives in the form of brief heavy showers and thunderstorms. More general rainfall occurs the remainder of the year as cold fronts and storm systems move through. Although cold spells during the winter send nighttime temperatures below freezing, snow is quite rare. In most winters, a few light snowfalls occur over inland areas. Central Argentina boasts a successful agricultural business, with crops grown on the Pampas south and west of Buenos Aires. Much of the area is used for
Rabbits are small mammals in the family Leporidae of the order Lagomorpha. Oryctolagus cuniculus includes the European rabbit species and its descendants, the world's 305 breeds of domestic rabbit. Sylvilagus includes 13 wild rabbit species, among them the 7 types of cottontail; the European rabbit, introduced on every continent except Antarctica, is familiar throughout the world as a wild prey animal and as a domesticated form of livestock and pet. With its widespread effect on ecologies and cultures, the rabbit is, in many areas of the world, a part of daily life—as food, clothing, a companion, as a source of artistic inspiration. Male rabbits are called bucks. An older term for an adult rabbit is coney. Another term for a young rabbit is bunny, though this term is applied informally to rabbits especially domestic ones. More the term kit or kitten has been used to refer to a young rabbit. A group of rabbits is known as a nest. A group of baby rabbits produced from a single mating is referred to as a litter, a group of domestic rabbits living together is sometimes called a herd.
Rabbits and hares were classified in the order Rodentia until 1912, when they were moved into a new order, Lagomorpha. Below are some of the species of the rabbit. Order Lagomorpha Family Leporidae Hares are precocial, born mature and mobile with hair and good vision, while rabbits are altricial, born hairless and blind, requiring closer care. Hares live a solitary life in a simple nest above the ground, while most rabbits live in social groups underground in burrows or warrens. Hares are larger than rabbits, with ears that are more elongated, with hind legs that are larger and longer. Hares have not been domesticated, while descendants of the European rabbit are bred as livestock and kept as pets. Rabbits have long been domesticated. Beginning in the Middle Ages, the European rabbit has been kept as livestock, starting in ancient Rome. Selective breeding has generated a wide variety of rabbit breeds, many of which are kept as pets; some strains of rabbit have been bred as research subjects. As livestock, rabbits are bred for their fur.
The earliest breeds were important sources of meat, so became larger than wild rabbits, but domestic rabbits in modern times range in size from dwarf to giant. Rabbit fur, prized for its softness, can be found in a broad range of coat colors and patterns, as well as lengths; the Angora rabbit breed, for example, was developed for its long, silky fur, hand-spun into yarn. Other domestic rabbit breeds have been developed for the commercial fur trade, including the Rex, which has a short plush coat; because the rabbit's epiglottis is engaged over the soft palate except when swallowing, the rabbit is an obligate nasal breather. Rabbits have two sets of one behind the other; this way they can be distinguished from rodents, with which they are confused. Carl Linnaeus grouped rabbits and rodents under the class Glires. However, recent DNA analysis and the discovery of a common ancestor has supported the view that they do share a common lineage, thus rabbits and rodents are now referred to together as members of the superorder Glires.
Since speed and agility are a rabbit's main defenses against predators, rabbits have large hind leg bones and well developed musculature. Though plantigrade at rest, rabbits are on their toes while running, assuming a more digitigrade form. Rabbits use their strong claws for defense; each front foot has four toes plus a dewclaw. Each hind foot has four toes. Most wild rabbits have full, egg-shaped bodies; the soft coat of the wild rabbit is agouti in coloration. The tail of the rabbit is dark on white below. Cottontails have white on the top of their tails; as a result of the position of the eyes in its skull, the rabbit has a field of vision that encompasses nearly 360 degrees, with just a small blind spot at the bridge of the nose. The anatomy of rabbits' hind limbs are structurally similar to that of other land mammals and contribute to their specialized form of locomotion; the Bones of the hind limbs consist of long bones as well as short bones. These bones are created through endochondral ossification during development.
Like most land mammals, the round head of the femur articulates with the acetabulum of the ox coxae. The femur articulates with the tibia, but not the fibula, fused to the tibia; the tibia and fibula articulate with the tarsals of the pes called the foot. The hind limbs of the rabbit are longer than the front limbs; this allows them to produce their hopping form of locomotion. Longer hind limbs are more capable of producing faster speeds. Hares, which have longer legs than cottontail rabbits, are able to move faster. Rabbits stay just on their toes; the hind feet have four long toes that allow for this and are webbed to prevent them from spreading when hopping. Rabbits do not have paw
A gaucho or gaúcho is a skilled horseman, reputed to be brave and unruly. The gaucho is a national symbol in Argentina and Uruguay, but is a strong culture in the far south region of Brazil. Gauchos became admired and renowned in legends and literature and became an important part of their regional cultural tradition. Beginning late in the 19th century, after the heyday of the gauchos, they were celebrated by South American writers; the gaucho in some respects resembled members of other nineteenth century rural, horse-based cultures such as the North American cowboy, the Chilean huaso, the Peruvian chalan or morochuco, the Venezuelan or Colombian llanero, the Hawaiian paniolo, the Mexican charro or the Portuguese campino. According to the Diccionario de la lengua española, in its historical sense a gaucho was "a mestizo who, in the 18th and 19th centuries, inhabited Argentina and Rio Grande do Sul in Brazil, was a migratory horseman, adept in cattle work" In Argentina and Uruguay today a gaucho is, according to the same source "A country person, experienced in traditional livestock farming".
Because historical gauchos were reputed to be brave, if unruly, the word is applied metaphorically to mean "Noble and generous", but "One, skilful in subtle tricks, crafty". In Portuguese the word gaúcho means "An inhabitant of the plains of Rio Grande do Sul or the pampas of Argentina descended from European man and indian woman who devotes himself to lassoing and raising cattle and horses". In its purest sense, gaucho referred to the nomadic outlaw inhabitants of the great plains of Argentina and Brazil. In current usage, gaucho designates the rural working class in general." There are several hypotheses concerning the origin of the term. It may derive from the Spanish term chaucho, in turn derived from a Turkish low-rank military term Chiaus, through Arabic shawsh which became broadly applied to any guard/watcher or aide; the first recorded use of the term dates to Argentine independence in 1816. Another scenario indicates the word may derive from the Portuguese gaudério, designated to the inhabitants of the vast regions of Rio Grande do Sul and Río de la Plata in the 18th century or the Portuguese garrucho that points to an instrument used by the gauchos to trap and hamstring cattle.
The 18th century chronicler Alonso Carrió de la Vandera speaks of gauderios when it mentions the gauchos or huasos as poorly dressed men. Another plausible origin is from a South American indigenous language, such as Mapudungun cauchu, kauču, or Quechua wahcha, it could derive from Arabic وحشة wahcha, which means the state of being lonely in the wilderness. An essential attribute of a gaucho was. "He has taken his first lessons in riding before he is well able to walk". Without a horse the gaucho felt; the naturalist William Henry Hudson recorded that the gauchos of his childhood used to say that a man without a horse was a man without legs. He described meeting a blind gaucho, obliged to beg for his food yet behaved with dignity and went about on horseback. Richard W. Slatta, the author of a scholarly work about gauchos, notes that the gaucho used horses to collect, drive or tame cattle, to draw fishing nets, to hunt ostriches, to snare partridges, to draw well water, − with the help of his friends − to ride to his own burial.
By reputation the quintessential gaucho caudillo Juan Manuel de Rosas could throw his hat on the ground and scoop it up while galloping his horse, without touching the saddle with his hand. For the gaucho, the horse was essential to his survival for, said Hudson: "he must every day traverse vast distances, see judge be ready at all times to encounter hunger and fatigue, violent changes of temperature and sudden perils". A popular copla was: It was the gaucho's passion to own all his steeds in matching colours. Hudson recalled: The gaucho, from the poorest worker on horseback to the largest owner of lands and cattle, has, or had in those days, a fancy for having all his riding-horses of one colour; every man as a rule had his tropilla — his own half a dozen or a dozen or more saddle-horses, he would have them all as nearly alike as possible, so that one man had chestnuts, another browns, silver- or iron-greys, fawns, cream-noses, or blacks, or whites, or piebalds. The caudillo El Chacho Peñalosa described the low point of his life as "In Chile − and on foot!"
The gaucho plays an important symbolic role in the nationalist feelings of this region that of Argentina and Uruguay. The epic poem Martín Fierro by José Hernández used the gaucho as a symbol against corruption and of Argentine national tradition, pitted against Europeanising tendencies. Martín Fierro, the hero of the poem, is drafted into the Argentine military for a border war and becomes an outlaw and fugitive; the image of the free gaucho is contrasted to the slaves who worked the northern Brazilian lands. Further literary descriptions are found in Ricardo Güiraldes' Don Segundo Sombra. Like the North American cowboys, as discussed in Richard W. Slatta, Cowboys of the Americas, gauchos were reputed to be strong, silent types, but proud and capable of violence when provoked; the gaucho tendency to violence over pett
Fat is one of the three main macronutrients, along with carbohydrate and protein. Fats molecules consist of carbon and hydrogen atoms, thus they are all hydrocarbon molecules. Examples include cholesterol and triglycerides; the terms "lipid", "oil" and "fat" are confused. "Lipid" is the general term, though a lipid is not a triglyceride. "Oil" refers to a lipid with short or unsaturated fatty acid chains, liquid at room temperature, while "fat" refers to lipids that are solids at room temperature – however, "fat" may be used in food science as a synonym for lipid. Fats, like other lipids, are hydrophobic, are soluble in organic solvents and insoluble in water. Fat is an important foodstuff for many forms of life, fats serve both structural and metabolic functions, they are a necessary part of the diet of most heterotrophs and are the most energy dense, thus the most efficient form of energy storage. Some fatty acids that are set free by the digestion of fats are called essential because they cannot be synthesized in the body from simpler constituents.
There are two essential fatty acids in human nutrition: linoleic acid. Other lipids needed by the body can be synthesized from other fats. Fats and other lipids are broken down in the body by enzymes called lipases produced in the pancreas. Fats and oils are categorized according to the number and bonding of the carbon atoms in the aliphatic chain. Fats that are saturated fats have no double bonds between the carbons in the chain. Unsaturated fats have one or more double bonded carbons in the chain; the nomenclature is based on the non-acid end of the chain. This end is called the n-end, thus alpha-linolenic acid is called an omega-3 fatty acid because the 3rd carbon from that end is the first double bonded carbon in the chain counting from that end. Some oils and fats are therefore called polyunsaturated fats. Unsaturated fats can be further divided into cis fats, which are the most common in nature, trans fats, which are rare in nature. Unsaturated fats can be altered by reaction with hydrogen effected by a catalyst.
This action, called hydrogenation, tends to break all the double bonds and makes a saturated fat. To make vegetable shortening liquid cis-unsaturated fats such as vegetable oils are hydrogenated to produce saturated fats, which have more desirable physical properties e.g. they melt at a desirable temperature, store well, whereas polyunsaturated oils go rancid when they react with oxygen in the air. However, trans fats are generated during hydrogenation as contaminants created by an unwanted side reaction on the catalyst during partial hydrogenation. Saturated fats can stack themselves in a packed arrangement, so they can solidify and are solid at room temperature. For example, animal fats tallow and lard are solids. Olive and linseed oils on the other hand are liquid. Fats serve both as energy sources for the body, as stores for energy in excess of what the body needs immediately; each gram of fat when burned or metabolized releases about 9 food calories. Fats are broken down in the healthy body to release their constituents and fatty acids.
Glycerol itself can be converted to glucose by the liver and so become a source of energy. There are many different kinds of fats. All fats are derivatives of fatty acids and glycerol. Most fats are glycerides triglycerides. One chain of fatty acid is bonded to each of the three -OH groups of the glycerol by the reaction of the carboxyl end of the fatty acid with the alcohol. Water is eliminated and the carbons are linked by an -O- bond through dehydration synthesis; this process is called esterification and fats are therefore esters. As a simple visual illustration, if the kinks and angles of these chains were straightened out, the molecule would have the shape of a capital letter E; the fatty acids would each be a horizontal line. Fats therefore have "ester" bonds; the properties of any specific fat molecule depend on the particular fatty acids. Fatty acids form a family of compounds that are composed of increasing numbers of carbon atoms linked into a zig-zag chain; the more carbon atoms there are in any fatty acid, the longer its chain will be.
Long chains are more susceptible to intermolecular forces of attraction, so the longer ones melt at a higher temperature. Fatty acid chains may differ by length categorized as short to long. Short-chain fatty acids are fatty acids with aliphatic tails of fewer than six carbons. Medium-chain fatty acids are fatty acids with aliphatic tails of 6–12 carbons, which can form medium-chain triglycerides. Long-chain fatty acids are fatty acids with aliphatic tails of 13 to 21 carbons. Long chain fatty acids are fatty acids with aliphatic tails of 22 or more carbons. Any of these aliphatic fatty acid chains may be glycerated and the resultant fats may have tails of different lengths from short triformin to long, e.g. cerotic acid, or hexacosanoic acid, a 26-carbon long-chain saturated fatty acid. Long chain fats are exemplified by tallow. Most fats found in foo
The Voyage of the Beagle
The Voyage of the Beagle is the title most given to the book written by Charles Darwin and published in 1839 as his Journal and Remarks, bringing him considerable fame and respect. This was the third volume of The Narrative of the Voyages of H. M. Ships Adventure and Beagle, the other volumes of which were written or edited by the commanders of the ships. Journal and Remarks covers Darwin's part in the second survey expedition of the ship HMS Beagle. Due to the popularity of Darwin's account, the publisher reissued it in 1839 as Darwin's Journal of Researches, the revised second edition published in 1845 used this title. A republication of the book in 1905 introduced the title The Voyage of the "Beagle", by which it is now best known; the Beagle sailed from Plymouth Sound on 27 December 1831 under the command of Captain Robert FitzRoy. While the expedition was planned to last two years, it lasted five—the Beagle did not return until 2 October 1836. Darwin spent most of this time exploring on land.
The book is a vivid travel memoir as well as a detailed scientific field journal covering biology and anthropology that demonstrates Darwin's keen powers of observation, written at a time when Western Europeans were exploring and charting the whole world. Although Darwin revisited some areas during the expedition, for clarity the chapters of the book are ordered by reference to places and locations rather than by date. Darwin's notes made during the voyage include comments hinting at his changing views on the fixity of species. On his return, he wrote the book based on these notes, at a time when he was first developing his theories of evolution through common descent and natural selection; the book includes some suggestions of his ideas in the second edition of 1845. Darwin was invited by FitzRoy to contribute the natural history section to the captain's account of the Beagle's voyage. Using his field notes and the journal which he had been sending home for his family to read, he completed this section by September 1837.
FitzRoy had to edit the notes of the previous captain of the Beagle, as well as write his own account of the voyage and the previous expeditions of two ships. The account was completed and published as a four-volume set in May 1839 as the Narrative of the Surveying Voyages of His Majesty's Ships Adventure and Beagle. Volume one covers the first voyage under Commander Phillip Parker King, volume two is FitzRoy's account of the second voyage. Darwin's Journal and Remarks, 1832—1835 forms the third volume, the fourth volume is a lengthy appendix. FitzRoy's account includes Remarks with reference to the Deluge in which he recanted his earlier interest in the geological writings of Charles Lyell and his remarks to Darwin during the expedition that sedimentary features they saw "could never have been effected by a forty days' flood", asserting his renewed commitment to a literal reading of the Bible, he had married on the ship's return, his wife was religious. Darwin's contribution proved remarkably popular and the publisher, Henry Colburn of London, took it upon himself to reissue Darwin's text in August with a new title page as Journal of Researches into the Geology and Natural History of the various countries visited by H.
M. S. Beagle without seeking Darwin's permission or paying him a fee; the second edition of 1845 incorporated extensive revisions made in the light of interpretation of the field collections and developing ideas on evolution. This edition was commissioned by the publisher John Murray, who paid Darwin a fee of £150 for the copyright; the full title was modified to Journal of Researches into the Natural History and Geology of the countries visited during the voyage of H. M. S. Beagle round the world. In the first edition, Darwin remarks in regard to the similarity of Galápagos wildlife to that on the South American continent, "The circumstance would be explained, according to the views of some authors, by saying that the creative power had acted according to the same law over a wide area". Darwin notes the gradations in size of the beaks of species of finches, suspects that species "are confined to different islands", "But there is not space in this work, to enter into this curious subject." Editions hint at his new ideas on evolution: Considering the small size of these islands, we feel the more astonished at the number of their aboriginal beings, at their confined range... within a period geologically recent the unbroken ocean was here spread out.
Hence, both in space and time, we seem to be brought somewhat near to that great fact – that mystery of mysteries – the first appearance of new beings on this earth. Speaking of the finches with their gradations in size of beaks, he writes "one might fancy that from an original paucity of birds in this archipelago, one species had been taken and modified for different ends." In 1890 John Murray published an illustrated edition of the book, at the suggestion of the artist Robert Taylor Pritchett, known for accompanying voyages of the RYS Wanderer and Sunbeam, producing pictures used in books on these cruises. In his foreword to this edition of Journal and Researches, Murray said that most "of the views given in this work are from sketches made on the spot by Mr. Pritchett, with Mr. Darwin's book by his side", the illustrations had been "chosen and verified with the utmost care and pains". For readability, the chapters of the book are arranged geographically rather than in an exact chronological sequence of places Darwin visited or revisited.
The main headings of each chapter give a good idea of where he went, but not the e