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Lactic acid

Lactic acid is an organic acid. It has a molecular formula CH3CHCOOH, it is white in solid state and it is miscible with water. While in liquid state it is a colorless solution. Production includes both artificial synthesis as well as natural sources. Lactic acid is an alpha-hydroxy acid due to the presence of carboxyl group adjacent to the hydroxyl group, it is used as a synthetic intermediate in many organic synthesis industries and in various biochemical industries. The conjugate base of lactic acid is called lactate. In solution, it can ionize a proton from the carboxyl group, producing the lactate ion CH3CHCO−2. Compared to acetic acid, its pKa is 1 unit less, meaning lactic acid is ten times more acidic than acetic acid; this higher acidity is the consequence of the intramolecular hydrogen bonding between the α-hydroxyl and the carboxylate group. Lactic acid is chiral. One is known as L--lactic acid or -lactic acid and the other, its mirror image, is D--lactic acid or -lactic acid. A mixture of the two in equal amounts is called racemic lactic acid.

Lactic acid is hygroscopic. DL-Lactic acid is miscible with water and with ethanol above its melting point, around 17 or 18 °C. D-Lactic acid and L-lactic acid have a higher melting point. Lactic acid produced by fermentation of milk is racemic, although certain species of bacteria produce -lactic acid. On the other hand, lactic acid produced by anaerobic respiration in animal muscles has the configuration and is sometimes called "sarcolactic" acid, from the Greek "sarx" for flesh. In animals, L-lactate is produced from pyruvate via the enzyme lactate dehydrogenase in a process of fermentation during normal metabolism and exercise, it does not increase in concentration until the rate of lactate production exceeds the rate of lactate removal, governed by a number of factors, including monocarboxylate transporters and isoform of LDH, oxidative capacity of tissues. The concentration of blood lactate is 1–2 mM at rest, but can rise to over 20 mM during intense exertion and as high as 25 mM afterward.

In addition to other biological roles, L-lactic acid is the primary endogenous agonist of hydroxycarboxylic acid receptor 1, a Gi/o-coupled G protein-coupled receptor. In industry, lactic acid fermentation is performed by lactic acid bacteria, which convert simple carbohydrates such as glucose, sucrose, or galactose to lactic acid; these bacteria can grow in the mouth. In medicine, lactate is one of the main components of lactated Ringer's solution and Hartmann's solution; these intravenous fluids consist of sodium and potassium cations along with lactate and chloride anions in solution with distilled water in concentrations isotonic with human blood. It is most used for fluid resuscitation after blood loss due to trauma, surgery, or burns. Swedish chemist Carl Wilhelm Scheele was the first person to isolate lactic acid in 1780 from sour milk; the name reflects the lact - combining form derived from the Latin word lac. In 1808, Jöns Jacob Berzelius discovered that lactic acid is produced in muscles during exertion.

Its structure was established by Johannes Wislicenus in 1873. In 1856, the role of Lactobacillus in the synthesis of lactic acid was discovered by Louis Pasteur; this pathway was used commercially by the German pharmacy Boehringer Ingelheim in 1895. In 2006, global production of lactic acid reached 275,000 tonnes with an average annual growth of 10%. Lactic acid is produced industrially by bacterial fermentation of carbohydrates, or by chemical synthesis from acetaldehyde that comes from coal or crude oil. In 2009, lactic acid was produced predominantly by fermentation. Production of racemic lactic acid consisting of a 1:1 mixture of D and L stereoisomers, or of mixtures with up to 99.9% L-lactic acid, is possible by microbial fermentation. Industrial scale production of D-lactic acid by fermentation is much more challenging. Fermented milk products are obtained industrially by fermentation of milk or whey by Lactobacillius species bacteria: Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus delbrueckii subsp.

Bulgaricus, Lactobacillus helveticus, Lactococcus lactis, Streptococcus salivarius subsp. Thermophilus; as a starting material for industrial production of lactic acid any carbohydrate source containing C5 and C6 sugars can be used. Pure sucrose, glucose from starch, raw sugar, beet juice are used. Lactic acid producing bacteria can be divided in two classes: homofermentative bacteria like Lactobacillus casei and Lactococcus lactis, producing two moles of lactate from one mole of glucose, heterofermentative species producing one mole of lactate from one mole of glucose as well as carbon dioxide and acetic acid/ethanol. Racemic lactic acid is produced by the addition of hydrogen cyanide to acetaldehyde and subsequent hydrolysis, forming lactonitrile; when hydrolysis performed by hydrochloric acid, ammonium chloride forms as a by-product. Synthesis of both racemic and enantiopure lactic acids is possible from other starting materials by application of catalytic procedures. L-Lactic acid is the primary endogenous agonist of hydroxycarboxylic acid receptor 1, a Gi/o-coupled G protein-coupled receptor.

During power exercises such as sprinting, when the rate of demand for energy is high, glucose is broken down and oxidized to pyruvat

History of Stockholm

The history of Stockholm, capital of Sweden, for many centuries coincided with the development of what is today known as Gamla stan, the Stockholm Old Town. Stockholm's raison d'être always was to be the Swedish capital and by far the largest city in the country; the name'Stockholm' splits into two distinct parts – Stock-holm, "Log-islet", but as no serious explanation to the name has been produced, various myths and legends have attempted to fill in the gap. According to a 17th-century myth the population at the viking settlement Birka decided to found a new settlement, to determine its location had a log bound with gold drifting in Lake Mälaren, it landed on present day Riddarholmen where today the Tower of Birger Jarl stands, a building, as a consequence, still erroneously mentioned as the oldest building in Stockholm. The most established explanation for the name are logs driven into the strait passing north of today's old town which dendrochronological examinations in the late 1970s dated to around 1000.

While no solid proofs exists, it is assumed the Three Crown Castle, which preceded the present Stockholm Palace, originated from these wooden structures, that the medieval city expanded around it in the mid 13th century. In a wider historical context, Stockholm can be thought of as the capital of the Lake Mälaren Region, as such can trace its origin back to at least two much older cities: Birka and Sigtuna, which still exists but dominated the region c. 1000–1240 — a capital, relocated at a number of occasions. The name Stockholm first appears in historical records in letters written by Birger Jarl and King Valdemar dated 1252. However, the two letters give no information about the appearance of the city and events during the following decades remain diffuse. While the absence of a perpendicular city plan in medieval Stockholm seems to indicate a spontaneous growth, it is known German merchants invited by Birger jarl played an important role in the foundation of the city. Under any circumstance, during the end of the 13th century, Stockholm grew to become not only the largest city in Sweden, but the de facto Swedish political centre and royal residence.

Thus, from its foundation, Stockholm has been the largest and most important Swedish city, inseparable from and dependent on the Swedish government. However, as late as the 16th century reigns of Kings Eric XIV and John III, whose Swedish government travelled with them elsewhere, the city was still not what could be called a national capital in modern terms. During the Kalmar Union, controlling Stockholm was crucial to anyone aspiring to control the kingdom, the city was repeatedly besieged by various Swedish-Danish factions. In 1471, Sten Sture the Elder defeated Christian I of Denmark at the Battle of Brunkeberg only to lose the city to Hans of Denmark in 1497. Sten Sture managed to seize power again in 1501 which resulted in a Danish blockade lasting 1502–1509 and a short peace. Hans' son Christian II of Denmark conquered it in 1520 and had many leading nobles and burghers of Stockholm beheaded in the so-called Stockholm Bloodbath; when King Gustav Vasa besieged and conquered the city three years an event which ended the Kalmar Union and the Swedish Middle Ages, he noted every second building in the city was abandoned.

By the end of the 15th century, the population in Stockholm can be estimated to 5,000–7,000 people, which made it a small town compared to several other contemporary European cities. On the other hand, it was far larger than any other city in Sweden. Many of its inhabitants were Germans and Finns, with the former forming a political and economic elite in the city. During the Middle Ages, export was administered by German merchants living by the squares Kornhamnstorg and Järntorget on the southern corner of the city. Regional peasantry supplied the city with food and raw materials, while the craftsmen in the city produced handicrafts, most of whom lived by the central square Stortorget or by the oldest two streets in Stockholm, the names of which still reflects their trade: Köpmangatan and Skomakargatan in the central part of the city. Other groups lived by Västerlånggatan and Österlånggatan. After Gustav Vasa's siege of Stockholm, he restored the privileges of the city, beneficiary to the burghers of the city.

The king maintained his control over the city by controlling the elections of aldermen and magistrates. By the mid-century, the numbers of officials increased in order to make the management of the city more professional and to ensure the state-controlled trade. Stockholm thus lost much of the independence it had had during the Middle Ages and became politically and financially bound to the state. During the reign of his sons, the city council remained escorted by a royal representative and both magistrates and aldermen were appointed by the king. Gustav Vasa invited the clergyman Olaus Petri to become the city secretary of Stockholm. With the two side-by-side, the new ideas of the Protestant Reformation could be implemented, sermons in the church where held in Swedish starting in 1525 and Latin abolished in 1530. A consequence of this development was a need for separate churches for the numerous German and Finnish-speaking citizens and during the 1530 the still-existent German and Finnish parishes were created.

The king was, not favourably disposed to older chapels and churches in the city, he ordered churches and monasteries on the ridges surrounding the city to be demolished, together with the numerous charitable institutions. Because

Stanton Glantz

Stanton Arnold Glantz is an American professor and leading tobacco control activist. Glantz is Professor of Medicine in the Division of Cardiology, the American Legacy Foundation Distinguished Professor of Tobacco Control, director of the Center for Tobacco Control Research and Education at the University of California, San Francisco School of Medicine. Glantz's research focuses on the health effects of tobacco smoking. Described as the "Ralph Nader of the anti-tobacco movement," Glantz is an activist for nonsmokers' rights and an advocate of public health policies to reduce smoking, he is the author including The Cigarette Papers and Primer of Biostatistics. Glantz is a member of the UCSF Cardiovascular Research Institute and Institute for Health Policy Studies, co-leader of the UCSF Comprehensive Cancer Center Tobacco Program, he was elected to the Institute of Medicine in 2005. In 2017, Glantz was sued by a former postdoctoral researcher for alleged sexual harassment and retaliation. UCSF settled the lawsuit for $150,000, while UCSF publicly denied the allegations.

In 2018, a second former employee sued Glantz for harassment. Glantz was the first of two children born in Cleveland, Ohio to Louis Glantz, an insurance salesman, Frieda, a real estate broker; as a youth, Glantz took a great interest in the Soviet Union's Sputnik 1 satellite. He was a member of the Boy Scouts of America, where he achieved the top rank of Eagle Scout, earned a Bronze Palm for further achievements. Glantz obtained a B. Sc. in aerospace engineering from the University of Cincinnati in 1969, an M. Sc. in applied mechanics from Stanford University in 1970, in 1973, a Ph. D. from Stanford in applied mechanics and engineering-economic systems. Concurrently with his studies, he worked at NASA's Manned Spacecraft Center, first as a student trainee as an aerospace engineer. In 1973, Glantz carried out postdoctoral research on the mathematical modeling of heart tissue at Stanford, at the UCSF, where he has worked since 1977, he served for 10 years as an Associate Editor of the Journal of the American College of Cardiology and is a member of the California State Scientific Review Panel on Toxic Air Contaminants of the California Air Resources Board.

He is married to Marsha, a home-care nurse, the father of journalist Aaron Glantz and daughter Frieda Glantz. In 2005, he was elected to the prestigious Institute of Medicine. Known for being blunt and abrasive, Glantz embraces his public image and controversial positions on smoking, on occasion wearing a "Here Comes Trouble" T-shirt. Glantz conducts research on a wide range of issues including the effects of secondhand smoke on the heart by studying reductions in heart attacks observed when smoke-free policies are enacted, how the tobacco industry fights tobacco control programs, his research on the effects of secondhand smoke on blood and blood vessels concludes that, in terms of heart disease, the effects of secondhand smoke are nearly as large as those of smoking. One such study demonstrated a large and rapid reduction in the number of people admitted to the hospital with heart attacks in Helena, after that community made all workplaces and public places smokefree. Glantz is author or coauthor of numerous publications related to secondhand smoke and tobacco control, as well as many papers on cardiovascular function and biostatistics.

He published the first study linking e-cigarettes to heart attacks in people. He has written several books, including the used Primer of Biostatistics, Primer of Applied Regression and Analysis of Variance. In total, he is the author of 4 books and over 400 scientific papers, including the first major review which identified secondhand smoke as a cause of heart disease and the landmark 1995 Journal of the American Medical Association summary of the Brown & Williamson documents, which showed that the tobacco industry knew nicotine was addictive and that smoking caused cancer 30 years ago; this publication was followed up with his book, The Cigarette Papers, which has played a key role in the ongoing litigation surrounding the tobacco industry. His book Tobacco Wars: Inside the California Battles chronicles the last quarter century of activism against the tobacco industry in California. Working with the UCSF Library, Glantz helped in making over 90 million pages of secret tobacco industry documents available via the internet on the UCSF Truth Tobacco Industry Documents known as the Legacy Tobacco Documents Library.

In February 2013, a paper co-authored by Glantz was published in the journal Tobacco Control. Entitled "‘To quarterback behind the scenes, third-party efforts’: the tobacco industry and the Tea Party", the paper detailed how the Tea Party political movement was funded and organized by organizations which were created by tobacco companies. In March 2014 Glantz released a study concluding that "e-cigarette use is aggravating rather than ameliorating the tobacco epidemic among youths." Thomas J. Glynn, a researcher at the American Cancer Society, responded that "The data in this study do not allow many of the broad conclusions that it draws" In 2018, the National Academies of Science and Medicine reviewed all the available evidence on e-cigarettes and youth and concluded that “there is substantial evidence that e-cigarette use incre