Education and early life.

Ivan Pavlov, the eldest of eleven children, was born in Ryazan, Russian Empire. His father, Peter Dmitrievich Pavlov (1823–1899), was a village Russian orthodox priest. His mother, Varvara Ivanovna Uspenskaya (1826–1890), was a devoted homemaker. As a child, Pavlov willingly participated in house duties such as doing the dishes and taking care of his siblings. He loved to garden, ride his bicycle, row, swim, and play gorodki; he devoted his summer vacations to these activities. Although able to read by the age of seven, Pavlov was seriously injured when he fell from a high wall onto a stone pavement. As a result of the injuries he sustained he did not begin formal schooling until he was 11 years old.  Pavlov attended the Ryazan church school before entering the local theological seminary. In 1870, however, he left the seminary without graduating in order to attend the university at St. Petersburg. There he enrolled in the physics and math department and took natural science courses. In his fourth year, his first research project on the physiology of the nerves of the pancreas won him a prestigious university award. In 1875, Pavlov completed his course with an outstanding record and received the degree of Candidate of Natural Sciences. Impelled by his overwhelming interest in physiology, Pavlov decided to continue his studies and proceeded to the Imperial Academy of Medical Surgery. While at the Academy, Pavlov became an assistant to his former teacher, Elias von Cyon. He left the department when de Cyon was replaced by another instructor.  After some time, Pavlov obtained a position as a laboratory assistant to Konstantin Nikolaevich Ustimovich at the physiological department of the Veterinary Institute. For two years, Pavlov investigated the circulatory system for his medical dissertation. In 1878, Professor S. P. Botkin, a famous Russian clinician, invited the gifted young physiologist to work in the physiological laboratory as the clinic's chief. In 1879, Pavlov graduated from the Medical Military Academy with a gold medal award for his research work. After a competitive examination, Pavlov won a fellowship at the Academy for postgraduate work. The fellowship and his position as director of the Physiological Laboratory at Botkin's clinic enabled Pavlov to continue his research work. In 1883, he presented his doctor's thesis on the subject of "The centrifugal nerves of the heart" and posited the idea of "nervism" and the basic principles on the trophic function of the nervous system. Additionally, his collaboration with the Botkin Clinic produced evidence of a basic pattern in the regulation of reflexes in the activity of circulatory organs.

Influences.

He was inspired to pursue a scientific career by D. I. Pisarev, a literary critique and natural science advocate of the time and I. M. Sechenov, a Russian physiologist, whom Pavlov described as 'The father of physiology'.

Career.

After completing his doctorate, Pavlov went to Germany where he studied in Leipzig with Carl Ludwig and Eimear Kelly in the Heidenhain laboratories in Breslau. He remained there from 1884 to 1886. Heidenhain was studying digestion in dogs, using an exteriorized section of the stomach. However, Pavlov perfected the technique by overcoming the problem of maintaining the external nerve supply. The exteriorized section became known as the Heidenhain or Pavlov pouch.  In 1886, Pavlov returned to Russia to look for a new position. His application for the chair of physiology at the University of Saint Petersburg was rejected. Eventually, Pavlov was offered the chair of pharmacology at Tomsk University in Siberia and at the University of Warsaw in Poland. He did not take up either post. In 1890, he was appointed the role of professor of Pharmacology at the Military Medical Academy and occupied the position for five years. In 1891, Pavlov was invited to the Institute of Experimental Medicine in St. Petersburg to organize and direct the Department of Physiology.  Over a 45-year period, under his direction, the Institute became one of the most important centers of physiological research in the world. Pavlov continued to direct the Department of Physiology at the Institute, while taking up the chair of physiology at the Medical Military Academy in 1895. Pavlov would head the physiology department at the Academy continuously for three decades.  Starting in 1901, Pavlov was nominated over four successive years for the Nobel Prize in Physiology or Medicine. He did not win the prize until 1904 because his previous nominations were not specific to any discovery, but based on a variety of laboratory findings. When Pavlov received the Nobel Prize it was specified that he did so "in recognition of his work on the physiology of digestion, through which knowledge on vital aspects of the subject has been transformed and enlarged".  It was at the Institute of Experimental Medicine that Pavlov carried out his classical experiments on the digestive glands. That is how he eventually won the Nobel prize mentioned above. Pavlov investigated the gastric function of dogs, and later, children, by externalizing a salivary gland so he could collect, measure, and analyze the saliva and what response it had to food under different conditions. He noticed that the dogs tended to salivate before food was actually delivered to their mouths, and set out to investigate this "psychic secretion", as he called it.  Pavlov's laboratory housed a full-scale kennel for the experimental animals. Pavlov was interested in observing their long-term physiological processes. This required keeping them alive and healthy in order to conduct chronic experiments, as he called them. These were experiments over time, designed to understand the normal functions of animals. This was a new kind of study, because previously experiments had been “acute,” meaning that the dog went through vivisection which ultimately killed the animal in the process.  A 1921 article by S. Morgulis in the journal "Science" was critical of Pavlov's work, raising concerns about the environment in which these experiments had been performed. Based on a report from H. G. Wells, claiming that Pavlov grew potatoes and carrots in his lab, the article stated, "It is gratifying to be assured that Professor Pavlov is raising potatoes only as a pastime and still gives the best of his genius to scientific investigation". That same year, Pavlov began holding laboratory meetings known as the 'Wednesday meetings' at which he spoke frankly on many topics, including his views on psychology. These meetings lasted until he died in 1936. Pavlov was highly regarded by the Soviet government, and he was able to continue his research until he reached a considerable age. He was praised by Lenin. Despite praise from the Soviet Union government, the money that poured in to support his laboratory, and the honours he was given, Pavlov made no attempts to conceal the disapproval and contempt with which he regarded Soviet Communism.  In 1923, he stated that he would not sacrifice even the hind leg of a frog to the type of social experiment that the regime was conducting in Russia. Four years later he wrote to Stalin, protesting at what was being done to Russian intellectuals and saying he was ashamed to be a Russian. After the murder of Sergei Kirov in 1934, Pavlov wrote several letters to Molotov criticizing the mass persecutions which followed and asking for the reconsideration of cases pertaining to several people he knew personally.  Conscious until his very last moment, Pavlov asked one of his students to sit beside his bed and to record the circumstances of his dying. He wanted to create unique evidence of subjective experiences of this terminal phase of life. Pavlov died of double pneumonia at the age of 86. He was given a grand funeral, and his study and laboratory were preserved as a museum in his honour.

Reflex system research.

Pavlov contributed to many areas of physiology and neurological sciences. Most of his work involved research in temperament, conditioning and involuntary reflex actions. Pavlov performed and directed experiments on digestion, eventually publishing "The Work of the Digestive Glands" in 1897, after 12 years of research. His experiments earned him the 1904 Nobel Prize in Physiology and Medicine. These experiments included surgically extracting portions of the digestive system from animals, severing nerve bundles to determine the effects, and implanting fistulas between digestive organs and an external pouch to examine the organ's contents. This research served as a base for broad research on the digestive system.  Further work on reflex actions involved involuntary reactions to stress and pain.

Research on types and properties of nervous systems.

Pavlov was always interested in biomarkers of temperament types described by Hippocrates and Galen. He called these biomarkers "properties of nervous systems" and identified three main properties: (1) strength, (2) mobility of nervous processes and (3) a balance between excitation and inhibition and derived four types based on these three properties. He extended the definitions of the four temperament types under study at the time: phlegmatic, choleric, sanguine, and melancholic, updating the names to "the strong and impetuous type, the strong equilibrated and quiet type, the strong equilibrated and lively type, and the weak type."  Pavlov and his researchers observed and began the study of transmarginal inhibition (TMI), the body's natural response of shutting down when exposed to overwhelming stress or pain by electric shock. This research showed how all temperament types responded to the stimuli the same way, but different temperaments move through the responses at different times. He commented "that the most basic inherited difference... was how soon they reached this shutdown point and that the quick-to-shut-down have a fundamentally different type of nervous system."

Pavlov on education.

The basics of Pavlov's classical conditioning serve as a historical backdrop for current learning theories. However, the Russian physiologist's initial interest in classical conditioning occurred almost by accident during one of his experiments on digestion in dogs. Considering that Pavlov worked closely with animals throughout many of his experiments, his early contributions were primarily about animal learning. However, the fundamentals of classical conditioning have been examined across many different organisms, including humans. The basic underlying principles of Pavlov's classical conditioning have extended to a variety of settings, such as classrooms and learning environments.  Classical conditioning focuses on using preceding conditions to alter behavioral reactions. The principles underlying classical conditioning have influenced preventative antecedent control strategies used in the classroom. Classical conditioning set the groundwork for the present day behavior modification practices, such as antecedent control. Antecedent events and conditions are defined as those conditions occurring before the behavior. Pavlov's early experiments used manipulation of events or stimuli preceding behavior (i.e., a tone) to produce salivation in dogs much like teachers manipulate instruction and learning environments to produce positive behaviors or decrease maladaptive behaviors. Although he did not refer to the tone as an antecedent, Pavlov was one of the first scientists to demonstrate the relationship between environmental stimuli and behavioral responses. Pavlov systematically presented and withdrew stimuli to determine the antecedents that were eliciting responses, which is similar to the ways in which educational professionals conduct functional behavior assessments. Antecedent strategies are supported by empirical evidence to operate implicitly within classroom environments. Antecedent-based interventions are supported by research to be preventative, and to produce immediate reductions in problem behaviors.

Legacy.

The concept for which Pavlov is famous is the "conditioned reflex" (or in his own words the "conditional reflex") he developed jointly with his assistant Ivan Filippovitch Tolochinov in 1901. He had come to learn this concept of conditioned reflex when examining the rates of salivations among dogs. Pavlov had learned that when a buzzer or metronome was sounded in subsequent time with food being presented to the dog in consecutive sequences, the dog would initially salivate when the food was presented. The dog would later come to associate the sound with the presentation of the food and salivate upon the presentation of that stimulus. Tolochinov, whose own term for the phenomenon had been "reflex at a distance", communicated the results at the Congress of Natural Sciences in Helsinki in 1903. Later the same year Pavlov more fully explained the findings, at the 14th International Medical Congress in Madrid, where he read a paper titled "The Experimental Psychology and Psychopathology of Animals".  As Pavlov's work became known in the West, particularly through the writings of John B. Watson and B. F. Skinner, the idea of "conditioning" as an automatic form of learning became a key concept in the developing specialism of comparative psychology, and the general approach to psychology that underlay it, behaviorism. Pavlov's work with classical conditioning was of huge influence to how humans perceive themselves, their behavior and learning processes and his studies of classical conditioning continue to be central to modern behavior therapy. The British philosopher Bertrand Russell observed that "[w]hether Pavlov's method's can be made to cover the whole of human behaviour is open to question, but at any rate they cover a very large field and within this field they have shown how to apply scientific methods with quantitative exactitude".  Pavlov's research on conditional reflexes greatly influenced not only science, but also popular culture. Pavlovian conditioning is a major theme in Aldous Huxley's dystopian novel, "Brave New World", and in Thomas Pynchon's "Gravity's Rainbow".  It is popularly believed that Pavlov always signaled the occurrence of food by ringing a bell. However, his writings record the use of a wide variety of stimuli, including electric shocks, whistles, metronomes, tuning forks, and a range of visual stimuli, in addition to the ring of a bell. In 1994, Catania cast doubt on whether Pavlov ever actually used a bell in his experiments. Littman tentatively attributed the popular imagery to Pavlov's contemporaries Vladimir Mikhailovich Bekhterev and John B. Watson. Roger K. Thomas, of the University of Georgia, however, said they had found "three additional references to Pavlov's use of a bell that strongly challenge Littman's argument". In reply, Littman suggested that Catania's recollection, that Pavlov did not use a bell in research, was "convincing... and correct".  In 1964 the eminent psychologist H. J. Eysenck reviewed Pavlov's "Lectures on Conditioned Reflexes" for the "British Medical Journal": Volume I – "Twenty-five Years of Objective Study of the Higher Nervous Activity of Animals", Volume II – "Conditioned Reflexes and Psychiatry".  The Pavlov Institute of Physiology of the Russian Academy of Sciences was founded by Pavlov in 1925 and named after him following his death.

Awards and honours.

Pavlov was awarded the Nobel Prize in Physiology or Medicine in 1904. He was elected a Foreign Member of the Royal Society (ForMemRS) in 1907 and was awarded the Royal Society's Copley Medal in 1915. He became a foreign member of the Royal Netherlands Academy of Arts and Sciences in 1907. Pavlov's dog, the Pavlovian session and Pavlov's typology are named in his honour. The asteroid 1007 Pawlowia and the lunar crater "Pavlov" were also named after him.

Personal life.

Ivan Pavlov married Seraphima Vasilievna Karchevskaya on 1 May 1881, whom he had met in 1878 or 1879 when she went to St. Petersburg to study at the Pedagogical Institute. Seraphima, called Sara for short, was born in 1855. In her later years, she suffered from ill health and died in 1947.  The first nine years of their marriage were marred by financial problems; Pavlov and his wife often had to stay with others in order to have a home, and for a time, the two lived apart so that they could find hospitality. Although their poverty caused despair, material welfare was a secondary consideration. Sara's first pregnancy ended in a miscarriage. When she conceived again, the couple took precautions, and she safely gave birth to their first child, a boy whom they named Mirchik; Sara became deeply depressed following Mirchik's sudden death in childhood.  Ivan and Sara eventually had four more children: Vladimir, Victor, Vsevolod, and Vera. Their youngest son, Vsevolod, died of pancreatic cancer in 1935, only one year before his father. Pavlov was an atheist.

Ivan Petrovich Pavlov (; 27 February 1936) was a Russian physiologist known primarily for his work in classical conditioning. From his childhood days Pavlov demonstrated intellectual curiosity along with an unusual energy which he referred to as "the instinct for research". Inspired by the progressive ideas which D. I. Pisarev, the most eminent of the Russian literary critics of the 1860s, and I. M. Sechenov, the father of Russian physiology, were spreading, Pavlov abandoned his religious career and devoted his life to science. In 1870, he enrolled in the physics and mathematics department at the University of Saint Petersburg in order to study natural science.

Ivan Petrovič Pavlov (, Rjazaň – 27. února 1936, Leningrad) byl ruský fyziolog, psycholog a lékař, který se zabýval studiem trávicích procesů a s nimi spojených reflexů. V roce 1904 obdržel za své výzkumy Nobelovu cenu za fyziologii a medicínu. Byl 24. nejcitovanějším psychologem ve 20. století.


Course.

The river begins at Santiago Pontones (province of Jaén), passes Calasparra, Cieza, Blanca, Murcia, Murcia, Beniaján, Orihuela, Rojales and ends in the Mediterranean Sea near Guardamar del Segura in the province of Alicante. Some of its tributaries are the Mundo (which starts near Riópar), the Alhárabe (which starts in Moratalla), the Mula and the Guadalentín.  The alluvial plain is called the "Vega del Segura" and is a very productive agricultural region growing a wide variety of fruit, vegetables and flowers. The "Vegas" are divided into three areas: "Alta", "Media" and "Baja" (upper, medium, and lower).

Recovery.

By the 1990s, the Segura had become one of the most polluted rivers in Europe, due to the canning industry and urban and agricultural residues originating in the densely populated area in the medium and lower areas of the basin. This fact combined with low or extreme low flows in the same areas –the agricultural use of water and summer drought could reduce the mean discharge to just around 2 to 3 m/s in Murcia city– made more difficult to dilute pollutants.  Public outcry peaked in 2001, with a demonstration gathering 40,000 people. A comprehensive action plan followed, the Segura River Project, developed by the Murcia Government's Regional Water Department, in partnership with the Segura River Authority and town councils in the region, to restore the health of the Segura River and to supply reclaimed water to the booming agriculture industry. Between 2001 and 2010, 100 water treatment plants and 350 kilometres of wastewater collection systems were built. In addition, a wastewater reclamation levy was established to finance the operation, maintenance and monitoring of these systems, applying the principle "the polluter pays".  By 2003 the quality of the Segura's water started improving. Since 2010, pollution has been unnoticeable, leading to the recovery of fauna and flora including increased otter population in parts of the river they had once abandoned. Birds now rest at two recovered wetland areas recognised by the Ramsar Convention, during their migration between Europe and Africa. In addition, around 110 million m of reclaimed water is reused annually for agriculture in the region.  With the river coming back to life, by 2013, otters and eels –both species particularly sensitive to water pollutants– had repopulated large tracts of the river where they had been absent for decades.  As of 2015 the Segura River Project is a finalist for the 2016 European Riverprize Awards, organized by the International River Foundation. This recognizes the fact that the Segura went from being one of the most polluted major rivers in Europe to being the Spanish river with the lowest average pollution (considering the average of all tracts of the river) in the span of just one decade.

Floods.

The Segura is usually in a state of semi-permanent drought, however, now and then, it does occasionally flood as the consequence of the torrential rains (cold drop), which typically take place once every 6–9 years approximately, always in Autumn and Spring.  Guadalentín river, a tributary of Segura, is the wildest European river.  In the twentieth century significant flooding occurred in 1946, 1948, 1973, 1982, 1987 and 1989. Since 1990 the lower reaches of the river have been canalized, removing meanders and hence improving the evacuation of flood waters. The new canal was put to the test in September 1997, in October 2000 and in December 2016 when heavy rainfall resulted in significant runoff.

Segura (, ; Latin: "Thader", Arabic: "شقورة", "War-Alabiat") is a medium-sized river in southeastern Spain. It has its source in the Sierra de Segura.

Segura () je řeka na jihovýchodě Španělsku (Andalusie, Kastilie-La Mancha, Valencia, Murcie). Je 341 km dlouhá. Povodí má rozlohu 16 200 km2.


Study and importance.

Cosmic dust was once solely an annoyance to astronomers, as it obscures objects they wish to observe. When infrared astronomy began, the dust particles were observed to be significant and vital components of astrophysical processes. Their analysis can reveal information about phenomena like the formation of the Solar System. For example, cosmic dust can drive the mass loss when a star is nearing the end of its life, play a part in the early stages of star formation, and form planets. In the Solar System, dust plays a major role in the zodiacal light, Saturn's B Ring spokes, the outer diffuse planetary rings at Jupiter, Saturn, Uranus and Neptune, and comets.  The interdisciplinary study of dust brings together different scientific fields: physics (solid-state, electromagnetic theory, surface physics, statistical physics, thermal physics), fractal mathematics, surface chemistry on dust grains) meteoritics, as well as every branch of astronomy and astrophysics. These disparate research areas can be linked by the following theme: the cosmic dust particles evolve cyclically; chemically, physically and dynamically. The evolution of dust traces out paths in which the Universe recycles material, in processes analogous to the daily recycling steps with which many people are familiar: production, storage, processing, collection, consumption, and discarding.  Observations and measurements of cosmic dust in different regions provide an important insight into the Universe's recycling processes; in the clouds of the diffuse interstellar medium, in molecular clouds, in the circumstellar dust of young stellar objects, and in planetary systems such as the Solar System, where astronomers consider dust as in its most recycled state. The astronomers accumulate observational ‘snapshots’ of dust at different stages of its life and, over time, form a more complete movie of the Universe's complicated recycling steps.  Parameters such as the particle's initial motion, material properties, intervening plasma and magnetic field determined the dust particle's arrival at the dust detector. Slightly changing any of these parameters can give significantly different dust dynamical behavior. Therefore, one can learn about where that object came from, and what is (in) the intervening medium.

Detection methods.

Cosmic dust can be detected by indirect methods that utilize the radiative properties of the cosmic dust particles.  Cosmic dust can also be detected directly ('in-situ') using a variety of collection methods and from a variety of collection locations. Estimates of the daily influx of extraterrestrial material entering the Earth's atmosphere range between 5 and 300 tonnes.  NASA collects samples of star dust particles in the Earth's atmosphere using plate collectors under the wings of stratospheric-flying airplanes. Dust samples are also collected from surface deposits on the large Earth ice-masses (Antarctica and Greenland/the Arctic) and in deep-sea sediments.  Don Brownlee at the University of Washington in Seattle first reliably identified the extraterrestrial nature of collected dust particles in the latter 1970s. Another source is the meteorites, which contain stardust extracted from them. Stardust grains are solid refractory pieces of individual presolar stars. They are recognized by their extreme isotopic compositions, which can only be isotopic compositions within evolved stars, prior to any mixing with the interstellar medium. These grains condensed from the stellar matter as it cooled while leaving the star.  In interplanetary space, dust detectors on planetary spacecraft have been built and flown, some are presently flying, and more are presently being built to fly. The large orbital velocities of dust particles in interplanetary space (typically 10–40 km/s) make intact particle capture problematic. Instead, in-situ dust detectors are generally devised to measure parameters associated with the high-velocity impact of dust particles on the instrument, and then derive physical properties of the particles (usually mass and velocity) through laboratory calibration (i.e. impacting accelerated particles with known properties onto a laboratory replica of the dust detector). Over the years dust detectors have measured, among others, the impact light flash, acoustic signal and impact ionisation. Recently the dust instrument on Stardust captured particles intact in low-density aerogel.  Dust detectors in the past flew on the HEOS-2, "Helios", "Pioneer 10", "Pioneer 11", "Giotto", "Galileo" and "Cassini" space missions, on the Earth-orbiting LDEF, EURECA, and Gorid satellites, and some scientists have utilized the "Voyager 1" and "2" spacecraft as giant Langmuir probes to directly sample the cosmic dust. Presently dust detectors are flying on the "Ulysses", Proba, "Rosetta", "Stardust", and the "New Horizons" spacecraft. The collected dust at Earth or collected further in space and returned by sample-return space missions is then analyzed by dust scientists in their respective laboratories all over the world. One large storage facility for cosmic dust exists at the NASA Houston JSC.  Infrared light can penetrate cosmic dust clouds, allowing us to peer into regions of star formation and the centers of galaxies. NASA's Spitzer Space Telescope is the largest infrared telescope yet launched into space. It was carried by a Delta rocket from Cape Canaveral, Florida on 25 August 2003. During its mission, Spitzer obtained images and spectra by detecting the thermal radiation emitted by objects in space between wavelengths of 3 and 180 micrometres. Most of this infrared radiation is blocked by the Earth's atmosphere and cannot be observed from the ground. Findings from the Spitzer have revitalized the studies of cosmic dust. One report showed some evidence that cosmic dust is formed near a supermassive black hole.  Another detection mechanism is polarimetry. Dust grains are not spherical and tend to align to interstellar magnetic fields, preferentially polarizing starlight that passes through dust clouds. In nearby interstellar space, where interstellar reddening is not intense enough to be detected, high precision optical polarimetry has been used to glean the structure of dust within the Local Bubble.  In 2019, researchers found interstellar dust in Antarctica which they relate to the Local Interstellar Cloud. The detection of interstellar dust in Antarctica was done by the measurement of the radionuclides Fe-60 and Mn-53 by highly sensitive Accelerator mass spectrometry.

Radiative properties.

A dust particle interacts with electromagnetic radiation in a way that depends on its cross section, the wavelength of the electromagnetic radiation, and on the nature of the grain: its refractive index, size, etc. The radiation process for an individual grain is called its "emissivity", dependent on the grain's "efficiency factor". Furthermore, we have to specify whether the emissivity process is extinction, scattering, absorption, or polarisation. In the radiation emission curves, several important signatures identify the composition of the emitting or absorbing dust particles.  Dust particles can scatter light nonuniformly. Forward scattered light is light that is redirected slightly off its path by diffraction, and back-scattered light is reflected light.  The scattering and extinction ("dimming") of the radiation gives useful information about the dust grain sizes. For example, if the object(s) in one's data is many times brighter in forward-scattered visible light than in back-scattered visible light, then we know that a significant fraction of the particles are about a micrometer in diameter.  The scattering of light from dust grains in long exposure visible photographs is quite noticeable in reflection nebulae, and gives clues about the individual particle's light-scattering properties. In X-ray wavelengths, many scientists are investigating the scattering of X-rays by interstellar dust, and some have suggested that astronomical X-ray sources would possess diffuse haloes, due to the dust.

Stardust.

Stardust grains (also called presolar grains by meteoriticists) are contained within meteorites, from which they are extracted in terrestrial laboratories. Stardust was a component of the dust in the interstellar medium before its incorporation into meteorites. The meteorites have stored those stardust grains ever since the meteorites first assembled within the planetary accretion disk more than four billion years ago. So-called carbonaceous chondrites are especially fertile reservoirs of stardust. Each stardust grain existed before the Earth was formed. "Stardust" is a scientific term referring to refractory dust grains that condensed from cooling ejected gases from individual presolar stars and incorporated into the cloud from which the Solar System condensed.  Many different types of stardust have been identified by laboratory measurements of the highly unusual isotopic composition of the chemical elements that comprise each stardust grain. These refractory mineral grains may earlier have been coated with volatile compounds, but those are lost in the dissolving of meteorite matter in acids, leaving only insoluble refractory minerals. Finding the grain cores without dissolving most of the meteorite has been possible, but difficult and labor-intensive (see presolar grains).  Many new aspects of nucleosynthesis have been discovered from the isotopic ratios within the stardust grains. An important property of stardust is the hard, refractory, high-temperature nature of the grains. Prominent are silicon carbide, graphite, aluminium oxide, aluminium spinel, and other such solids that would condense at high temperature from a cooling gas, such as in stellar winds or in the decompression of the inside of a supernova. They differ greatly from the solids formed at low temperature within the interstellar medium.  Also important are their extreme isotopic compositions, which are expected to exist nowhere in the interstellar medium. This also suggests that the stardust condensed from the gases of individual stars before the isotopes could be diluted by mixing with the interstellar medium. These allow the source stars to be identified. For example, the heavy elements within the silicon carbide (SiC) grains are almost pure S-process isotopes, fitting their condensation within AGB star red giant winds inasmuch as the AGB stars are the main source of S-process nucleosynthesis and have atmospheres observed by astronomers to be highly enriched in dredged-up s process elements.  Another dramatic example is given by the so-called supernova condensates, usually shortened by acronym to SUNOCON (from SUperNOva CONdensate) to distinguish them from other stardust condensed within stellar atmospheres. SUNOCONs contain in their calcium an excessively large abundance of Ca, demonstrating that they condensed containing abundant radioactive Ti, which has a 65-year half-life. The outflowing Ti nuclei were thus still "alive" (radioactive) when the SUNOCON condensed near one year within the expanding supernova interior, but would have become an extinct radionuclide (specifically Ca) after the time required for mixing with the interstellar gas. Its discovery proved the prediction from 1975 that it might be possible to identify SUNOCONs in this way. The SiC SUNOCONs (from supernovae) are only about 1% as numerous as are SiC stardust from AGB stars.  Stardust itself (SUNOCONs and AGB grains that come from specific stars) is but a modest fraction of the condensed cosmic dust, forming less than 0.1% of the mass of total interstellar solids. The high interest in stardust derives from new information that it has brought to the sciences of stellar evolution and nucleosynthesis.  Laboratories have studied solids that existed before the Earth was formed. This was once thought impossible, especially in the 1970s when cosmochemists were confident that the Solar System began as a hot gas virtually devoid of any remaining solids, which would have been vaporized by high temperature. The existence of stardust proved this historic picture incorrect.

Some bulk properties.

Cosmic dust is made of dust grains and aggregates into dust particles. These particles are irregularly shaped, with porosity ranging from "fluffy" to "compact". The composition, size, and other properties depend on where the dust is found, and conversely, a compositional analysis of a dust particle can reveal much about the dust particle's origin. General diffuse interstellar medium dust, dust grains in dense clouds, planetary rings dust, and circumstellar dust, are each different in their characteristics. For example, grains in dense clouds have acquired a mantle of ice and on average are larger than dust particles in the diffuse interstellar medium. "Interplanetary dust particles" (IDPs) are generally larger still. Most of the influx of extraterrestrial matter that falls onto the Earth is dominated by meteoroids with diameters in the range 50 to 500 micrometers, of average density 2.0 g/cm3 (with porosity about 40%). The total influx rate of meteoritic sities of most IDPs captured in the Earth's stratosphere range between 1 and 3 g/cm3, with an average density at about 2.0 g/cm3.  Other specific dust properties: in "circumstellar dust", astronomers have found molecular signatures of CO, silicon carbide, amorphous silicate, polycyclic aromatic hydrocarbons, water ice, and polyformaldehyde, among others (in the diffuse interstellar medium, there is evidence for silicate and carbon grains). "Cometary dust" is generally different (with overlap) from "asteroidal dust". Asteroidal dust resembles carbonaceous chondritic meteorites. Cometary dust resembles interstellar grains which can include silicates, polycyclic aromatic hydrocarbons, and water ice.

Dust grain formation.

The large grains in interstellar space are probably complex, with refractory cores that condensed within stellar outflows topped by layers acquired during incursions into cold dense interstellar clouds. That cyclic process of growth and destruction outside of the clouds has been modeled to demonstrate that the cores live much longer than the average lifetime of dust mass. Those cores mostly start with silicate particles condensing in the atmospheres of cool, oxygen-rich red-giants and carbon grains condensing in the atmospheres of cool carbon stars. Red giants have evolved or altered off the main sequence and have entered the giant phase of their evolution and are the major source of refractory dust grain cores in galaxies. Those refractory cores are also called stardust (section above), which is a scientific term for the small fraction of cosmic dust that condensed thermally within stellar gases as they were ejected from the stars. Several percent of refractory grain cores have condensed within expanding interiors of supernovae, a type of cosmic decompression chamber. Meteoriticists who study refractory stardust (extracted from meteorites) often call it presolar grains but that within meteorites is only a small fraction of all presolar dust. Stardust condenses within the stars via considerably different condensation chemistry than that of the bulk of cosmic dust, which accretes cold onto preexisting dust in dark molecular clouds of the galaxy. Those molecular clouds are very cold, typically less than 50K, so that ices of many kinds may accrete onto grains, in cases only to be destroyed or split apart by radiation and sublimation into a gas component. Finally, as the Solar System formed many interstellar dust grains were further modified by coalescence and chemical reactions in the planetary accretion disk. The history of the various types of grains in the early Solar System is complicated and only partially understood.  Astronomers know that the dust is formed in the envelopes of late-evolved stars from specific observational signatures. In infrared light, emission at 9.7 micrometres is a signature of silicate dust in cool evolved oxygen-rich giant stars. Emission at 11.5 micrometres indicates the presence of silicon carbide dust in cool evolved carbon-rich giant stars. These help provide evidence that the small silicate particles in space came from the ejected outer envelopes of these stars.  Conditions in interstellar space are generally not suitable for the formation of silicate cores. This would take excessive time to accomplish, even if it might be possible. The arguments are that: given an observed typical grain diameter "a", the time for a grain to attain "a", and given the temperature of interstellar gas, it would take considerably longer than the age of the Universe for interstellar grains to form. On the other hand, grains are seen to have recently formed in the vicinity of nearby stars, in nova and supernova ejecta, and in R Coronae Borealis variable stars which seem to eject discrete clouds containing both gas and dust. So mass loss from stars is unquestionably where the refractory cores of grains formed.  Most dust in the Solar System is highly processed dust, recycled from the material out of which the Solar System formed and subsequently collected in the planetesimals, and leftover solid material such as comets and asteroids, and reformed in each of those bodies' collisional lifetimes. During the Solar System's formation history, the most abundant element was (and still is) H. The metallic elements: magnesium, silicon, and iron, which are the principal ingredients of rocky planets, condensed into solids at the highest temperatures of the planetary disk. Some molecules such as CO, N, NH, and free oxygen, existed in a gas phase. Some molecules, for example, graphite (C) and SiC would condense into solid grains in the planetary disk; but carbon and SiC grains found in meteorites are presolar based on their isotopic compositions, rather than from the planetary disk formation. Some molecules also formed complex organic compounds and some molecules formed frozen ice mantles, of which either could coat the "refractory" (Mg, Si, Fe) grain cores. Stardust once more provides an exception to the general trend, as it appears to be totally unprocessed since its thermal condensation within stars as refractory crystalline minerals. The condensation of graphite occurs within supernova interiors as they expand and cool, and do so even in gas containing more oxygen than carbon, a surprising carbon chemistry made possible by the intense radioactive environment of supernovae. This special example of dust formation has merited specific review.  Planetary disk formation of precursor molecules was determined, in large part, by the temperature of the solar nebula. Since the temperature of the solar nebula decreased with heliocentric distance, scientists can infer a dust grain's origin(s) with knowledge of the grain's materials. Some materials could only have been formed at high temperatures, while other grain materials could only have been formed at much lower temperatures. The materials in a single interplanetary dust particle often show that the grain elements formed in different locations and at different times in the solar nebula. Most of the matter present in the original solar nebula has since disappeared; drawn into the Sun, expelled into interstellar space, or reprocessed, for example, as part of the planets, asteroids or comets.  Due to their highly processed nature, IDPs (interplanetary dust particles) are fine-grained mixtures of thousands to millions of mineral grains and amorphous components. We can picture an IDP as a "matrix" of material with embedded elements which were formed at different times and places in the solar nebula and before the solar nebula's formation. Examples of embedded elements in cosmic dust are GEMS, chondrules, and CAIs.

From the solar nebula to Earth.

The arrows in the adjacent diagram show one possible path from a collected interplanetary dust particle back to the early stages of the solar nebula.  We can follow the trail to the right in the diagram to the IDPs that contain the most volatile and primitive elements. The trail takes us first from interplanetary dust particles to chondritic interplanetary dust particles. Planetary scientists classify chondritic IDPs in terms of their diminishing degree of oxidation so that they fall into three major groups: the carbonaneous, the ordinary, and the enstatite chondrites. As the name implies, the carbonaceous chondrites are rich in carbon, and many have anomalies in the isotopic abundances of H, C, N, and O (Jessberger, 2000). From the carbonaceous chondrites, we follow the trail to the most primitive materials. They are almost completely oxidized and contain the lowest condensation temperature elements ("volatile" elements) and the largest amount of organic compounds. Therefore, dust particles with these elements are thought to have been formed in the early life of the Solar System. The volatile elements have never seen temperatures above about 500 K, therefore, the IDP grain "matrix" consists of some very primitive Solar System material. Such a scenario is true in the case of comet dust. The provenance of the small fraction that is stardust (see above) is quite different; these refractory interstellar minerals thermally condense within stars, become a small component of interstellar matter, and therefore remain in the presolar planetary disk. Nuclear damage tracks are caused by the ion flux from solar flares. Solar wind ions impacting on the particle's surface produce amorphous radiation damaged rims on the particle's surface. And spallogenic nuclei are produced by galactic and solar cosmic rays. A dust particle that originates in the Kuiper Belt at 40 AU would have many more times the density of tracks, thicker amorphous rims and higher integrated doses than a dust particle originating in the main-asteroid belt.  Based on 2012 computer model studies, the complex organic molecules necessary for life (Extraterrestrial organic molecules) may have formed in the protoplanetary disk of dust grains surrounding the Sun before the formation of the Earth. According to the computer studies, this same process may also occur around other stars that acquire planets.  In September 2012, NASA scientists reported that polycyclic aromatic hydrocarbons (PAHs), subjected to interstellar medium (ISM) conditions, are transformed, through hydrogenation, oxygenation and hydroxylation, to more complex organics – "a step along the path toward amino acids and nucleotides, the raw materials of proteins and DNA, respectively". Further, as a result of these transformations, the PAHs lose their spectroscopic signature which could be one of the reasons "for the lack of PAH detection in interstellar ice grains, particularly the outer regions of cold, dense clouds or the upper molecular layers of protoplanetary disks."  In February 2014, NASA announced a greatly upgraded database for detecting and monitoring polycyclic aromatic hydrocarbons (PAHs) in the universe. According to NASA scientists, over 20% of the carbon in the Universe may be associated with PAHs, possible starting materials for the formation of life. PAHs seem to have been formed shortly after the Big Bang, are abundant in the Universe, and are associated with new stars and exoplanets.  In March 2015, NASA scientists reported that, for the first time, complex DNA and RNA organic compounds of life, including uracil, cytosine and thymine, have been formed in the laboratory under outer space conditions, using starting chemicals, such as pyrimidine, found in meteorites. Pyrimidine, like polycyclic aromatic hydrocarbons (PAHs), the most carbon-rich chemical found in the Universe, may have been formed in red giants or in interstellar dust and gas clouds, according to the scientists.

Some "dusty" clouds in the universe.

The Solar System has its own interplanetary dust cloud, as do extrasolar systems. There are different types of nebulae with different physical causes and processes: diffuse nebula, infrared (IR) reflection nebula, supernova remnant, molecular cloud, HII regions, photodissociation regions, and dark nebula.  Distinctions between those types of nebula are that different radiation processes are at work. For example, H II regions, like the Orion Nebula, where a lot of star-formation is taking place, are characterized as thermal emission nebulae. Supernova remnants, on the other hand, like the Crab Nebula, are characterized as nonthermal emission (synchrotron radiation).  Some of the better known dusty regions in the Universe are the diffuse nebulae in the Messier catalog, for example: M1, M8, M16, M17, M20, M42, M43.  Some larger dust catalogs are Sharpless (1959) A Catalogue of HII Regions, Lynds (1965) Catalogue of Bright Nebulae, Lynds (1962) Catalogue of Dark Nebulae, van den Bergh (1966) Catalogue of Reflection Nebulae, Green (1988) Rev. Reference Cat. of Galactic SNRs, The National Space Sciences Data Center (NSSDC), and CDS Online Catalogs.

Dust sample return.

The Discovery program's "Stardust" mission, was launched on 7 February 1999 to collect samples from the coma of comet Wild 2, as well as samples of cosmic dust. It returned samples to Earth on 15 January 2006. In the spring of 2014, the recovery of particles of interstellar dust from the samples was announced.

Cosmic dust, also called extraterrestrial dust or space dust, is dust which exists in outer space, or has fallen on Earth. Most cosmic dust particles measure between a few molecules and 0.1 μm. Cosmic dust can be further distinguished by its astronomical location: intergalactic dust, interstellar dust, interplanetary dust (such as in the zodiacal cloud) and circumplanetary dust (such as in a planetary ring).

Kosmický prach či meziplanetární prach je označení pro meziplanetární hmotu o velikosti menší než je 1 milimetr, která se volně nachází v okolním vesmíru. Jedná se o drobná zrnka různorodého materiálu, který pochází z různých zdrojů (materiál z období formování soustavy, ohon komety, materiál vyvržený po srážce atd.)


Early life.

Luka Modrić was born on 9 September 1985 and was raised in the hamlet of Modrići which is a part of Zaton Obrovački, a village situated on the southern slopes of the mountain Velebit, north of the city of Zadar in SR Croatia, then a republic within SFR Yugoslavia. He is the oldest child of Stipe Modrić from Modrići and Radojka Dopuđ from Kruševo near Obrovac, both of whom initially worked in knitwear factory. Modrić mostly spent his early years in the house of his paternal grandfather after whom he was named, and was shepherding goats as a five-year-old. However, his childhood coincided with the Croatian War of Independence—in 1991, when the war escalated, his family were forced to flee the area. Modrić's grandfather Luka was

Club career.

Early years.

1990s–05: NK Zadar and development through loans.

Supported by his family, he participated in representative camps and trained in NK Zadar. He was under tutelage of coach Domagoj Bašić and the head of the youth academy, Tomislav Bašić. Tomislav Bašić, considered by Modrić as his "sporting father", said Modrić's father made him wooden shin guards because they had little money. However, Modrić later denied the story. Due to being considered too young and light, he was not signed by Croatian powerhouse Hajduk Split, the most representative football club in the region of Dalmatia. After displaying some talent, including at youth tournament in Italy,

Dinamo Zagreb.

2005–08: Breakthrough in Croatia.

In the 2005–06 season, Modrić signed a ten-year contract (his first long-term contract) with Dinamo Zagreb. With the contract's earnings, he bought a flat in Zadar for his family. He secured a place in Dinamo's first team, contributing 7 goals in 31 matches to help win the league. In the 2006–07 season, Dinamo again won the league, with Modrić making a similar contribution. He was the main provider for striker Eduardo, which helped Modrić win the Prva HNL Player of the Year award. The following season, Modrić as a team captain, led Dinamo's attempt

Tottenham Hotspur.

2008–10: Struggle and success in England.

Modrić agreed to transfer terms with Tottenham Hotspur on 26 April 2008. He was the first of many summer signings for manager Juande Ramos, and was also the Premier League's first summer transfer. Club chairman Daniel Levy promptly flew to Zagreb when Manchester City and Newcastle United became interested, and after signing a six-year contract, Tottenham confirmed the transfer fee paid was £16.5 million, equalling the club's record fee set by Darren Bent's move in 2007. He got number 14 jersey, later recalling that he wore it in honour of Johan Cruyff. Modrić made his competitive Premier League debut on 16 August in a 2–1 defeat to Middlesbrough at the Riverside Stadium

2010–12: Outgrowing Tottenham Hotspur.

On 11 September 2010, Modrić scored his first goal of the 2010–11 season in a 1–1 away draw at West Bromwich Albion. On 28 November, in a home match against Liverpool, Modrić scored one goal that was later credited as an own goal by Martin Škrtel. After a draw against Manchester United at White Hart Lane in January 2011, Redknapp praised Modrić, saying, "He was unbelievable. Magnificent. He's an amazing footballer, the little man takes the ball in the tightest areas with people around him, wriggling out of situations. He could play in any team in the world." Modrić also scored in Tottenham's 3–2 victory over Stoke City on 9 April, and converted a penalty at Anfield on 15 May in a 2–0 victory over Liverpool. Modrić helped Tottenham reach their first involvement in the UEFA Champions League. In the first match, against Inter Milan at the San Siro on 20 October, he exited the match early due to injury; Spurs lost 4–3, despite the tremendous efforts of Gareth Bale. On the return match at home, on 2 November, Modrić was given too much space to move and dictate the tempo of the match. He created and assisted for the first goal by Rafael van der Vaart in a 3–1 victory. In the next match, against Werder Bremen, Modrić scored the second goal. After a scoreless draw against Milan, Spurs were

Real Madrid.

2012–13: Becoming a starting eleven player in Real Madrid.

On 27 August 2012, Real Madrid announced they had agreed on a deal with Tottenham for an approximate £30 million transfer fee. Modrić signed a five-year contract with the Spanish club. Two days later, he made his Real Madrid debut against Barcelona in the second leg final of the 2012 Supercopa de España at the Santiago Bernabéu Stadium, replacing Mesut Özil in the 83rd minute. Madrid won the match, giving Modrić his first trophy with the club 36 hours after his signing was announced. Despite his positive debut, Modrić at first

2013–15: Best midfielder in Spain and "La Décima".

With the arrival of new manager Carlo Ancelotti, Modrić became one of the most frequent starters in the team, being partnered in midfield with Xabi Alonso to provide a balance of defence and attack. He was consistently the team's most efficient passer, averaging 90% accuracy in La Liga, and also having the most ball recoveries among the squad. He scored his first goal of the 2013–14 season in the last Champions League group match against Copenhagen, making it his fifth goal for the club, all five of

2015–17: Among best world players and "La Undécima" and "Duodécima".

For the 2015–16 season, Carlo Ancelotti was replaced by Rafael Benítez under whom Modrić continued to be a key midfield player. Modrić began the season assisting in September, November and December, and scoring in the 3–4 away win against Shakhtar Donetsk in the Champions League group stage. He sustained a muscular groin injury during an international match in October, initially suggesting an absence of two-to-three weeks. However, by 20 October, he had recovered in time for the match against Paris Saint-Germain.  With the arrival of new manager Zinedine Zidane in January 2016, the relationship between them was noted in the media, with Modrić described as "master of the game", and the crucial "connector" of the defence and attack. It was seen in the first three matches, wins against Deportivo de La Coruña and Sporting de Gijón and a draw against Real Betis, in which Modrić was praised for creating chances, his positioning and overall performance and influence. On 7 February, Modrić scored a winning goal from outside the box in a 1–2 away win against Granada. Modrić was a regular in the starting line-up

2017–18: Player of the year and third consecutive Champions League title.

With the departure of James Rodríguez to Bayern Munich, Modrić inherited the team's coveted number 10 jersey for the new 2017–18 season, replacing his previous number 19 jersey. In December, he won the 2017 FIFA Club World Cup with Real Madrid and received the Golden Ball award as the best player of the competition for his performance. His first goal of the season came in a 7–1 win over Deportivo de La Coruña on 21 January 2018. In the same month was for the second time included in the UEFA Team of the Year (2017). Modrić was a regular starter when Real Madrid won the 2017–18 UEFA Champions League, starting in the final victory against Liverpool which saw Madrid win their third consecutive title. For his performances throughout the campaign, Modrić was included in Champions League team of the season for the third consecutive time.<ref name="CL 2017/18 Team"></ref> He later received the UEFA Club Football Award for Best Midfielder of the Champions League season for the second consecutive time. In July 2018, it was announced Modrić's Real Madrid jersey was the most requested jersey of the club after

2018–20: Seventh season in Spain and Golden Foot.

The arrival of new manager Julen Lopetegui in August 2018 saw Modrić given a steady return to the first team as a substitute due to his lack of pre-season training after the 2018 World Cup. This included a substitute appearance in his team's 2–4 loss after extra time against Atlético Madrid in the UEFA Super Cup. His first start of the season came on 1 September in a 4–1 home win against Leganés, in which he assisted his side's third goal, scored by Karim Benzema. His 100th appearance in the UEFA club competition came on 19 September in a 3–0 home win against Roma, in which made an assist for the second goal, scored by Gareth Bale. On 22 December, Modrić won his fourth FIFA Club World Cup, scoring the first goal and assisting for the third in the final against Al Ain FC. On 13 and 19 January 2019, Modrić for the first time

International career.

Modrić began his international career at youth level, playing for the Croatian under-15, under-17, under-18, under-19 and under-21 teams. He debuted in March 2001 for the under-15 team coached by Martin Novoselac, but nevertheless his talent and psychological maturity, he did not become a regular starter and leading player until physically strengthened and debuted for under-18. Novoselac considers him as a model for all young players because is a result of a gradual and continuous work and effort, as well as talent. Modrić made his full international debut for Croatia on 1 March 2006 in a friendly match against Argentina in Basel, which Croatia won 3–2.

2006–08: 2006 World Cup and Euro 2008.

Modrić made two appearances at the 2006 FIFA World Cup finals as a substitute in the group fixtures against Japan, and Australia. With the appointment of new manager Slaven Bilić, Modrić earned greater recognition at international level; he scored his first goal in Croatia's 2–0 friendly win over Italy on 16 August 2006 in Livorno.  Modrić's performances ensured a regular place in the international side and he gave a successful showing in Croatia's UEFA Euro 2008 qualifying campaign, which included home and away victories against England. As a young midfielder, much was expected of Modrić; he was often dubbed "the Croatian Cruyff". Modrić scored Croatia's first goal

2008–16: Subsequent struggles.

In the 2010 World Cup qualifiers, Modrić scored three goals, against Kazakhstan, Andorra, and Ukraine; matching Ivica Olić, Ivan Rakitić and Eduardo. The team failed to qualify finishing one point behind second-placed Ukraine. After appearing in all of their UEFA Euro 2012 qualifying matches and scoring a goal against Israel, Modrić started in all three of Croatia group stage matches against the Republic of Ireland, Italy and Spain, but the team failed to progress. His most notable performance was against Spain. The most memorable moment of the match came when Modrić picked the ball on the halfway line skipping Spain's midfield trio, rushing down on the right to reach the penalty area where he evaded a defender and crossed from to Ivan Rakitić, but Iker Casillas saved this attempt. Because Croatia did not advance from the group stage, Modrić was not included in the Team of the Tournament, although "The Daily Telegraph" included him in

2016–2018: Golden Ball of 2018 World Cup.

For Croatia's 2018 World Cup qualifying campaign, Modrić became the new team captain. He scored a penalty against Greece in the second qualifying round, enabling his team to qualify for the World Cup. Croatia were placed in Group D alongside Argentina, Iceland and Nigeria. During the tournament, Modrić—along with Ivan Rakitić and Mario Mandžukić—were referred to as Croatia's second "Golden Generation". In Croatia's opening win against Nigeria, Modrić once again successfully executed a penalty kick and was named Man of the Match. He also scored in Croatia's subsequent 3–0 win over Argentina with a long-range shot from 25 yards (23 metres), also being named Man of the Match. After also featuring in the final group stage match, against Iceland, his performances in the first round of the tournament saw him ranked by "FourFourTwo", "The Daily Telegraph" and ESPN as the best player of the group stage.  In the round of 16 against Denmark on 1 July, with the score tied

2018–present: Post-World Cup period.

Modrić took part in all four matches in the inaugural edition of UEFA Nations League as Croatia finished at the bottom of the group following historical 6–0 away defeat to Spain in September and

Player profile.

Style of play.

A diminutive midfielder, Modrić is described as a quick and creative playmaker, with great vision, who is able to change the course of the game with incredibly deft passes and solo, long-range efforts. He plays with both feet in combination with his swift offensive positioning, off the ball.. He passes the ball accurately across long and short distances (passing range of perfection), even with the outside of his boot. His ball control, first

Position.

Modrić's complex game has brought him consistent success in the clubs for which he has played. Initially a trequartista or attacking midfielder at Dinamo Zagreb and in his early career at Tottenham, in the 2010–11 season he flourished in a central midfield role as a deep-lying playmaker (regista) who conducts the attack and creates chances for teammates. Afterwards, Modrić acknowledged the role that Harry Redknapp played in shaping of deep-lying his style, saying that dropping back enabled him "to read the game better" and show his full "creativity". Although a central midfielder, Modrić is also a hard-working player

Reception.

Modrić is widely regarded as one of most well-rounded and effective midfielders in the world. According to Jonathan Wilson, what sets apart Modrić from old-school playmakers (number ten) like Juan Román Riquelme is the universality due to increased defensive responsibility, a quality which was insisted by Valeriy Lobanovskyi and Arrigo Sacchi that should make a modern footballer.  Modrić's skill in the game was recognised early by Dragan Stojković (Piksi), who stated, "I saw a small blond boy who played exactly like I would. Ideas he was showing then on the terrain were fascinating". Piksi considered him, along with Xavi and Andrés Iniesta, as the most intelligent player. Johan Cruyff said Modrić's quality and influence on the game depend on the freedom he gets. Paul Scholes, who played several times against Modrić, said in an interview with the "Manchester Evening News" in 2011, "Of the three (Samir Nasri and Wesley Sneijder), Modrić, has been the one I have been most impressed with, [and] whenever we played Tottenham, he was the one who stood out". In 2014, Zinedine Zidane included Modrić in his best XI currently playing the game, while in January 2016 in

Personal life.

Modrić married Vanja Bosnić in May 2010 in the Croatian capital Zagreb in a private ceremony after four years of dating, and a year later in church. Their son, Ivano, was born on 6 June 2010. Their daughter, Ema, was born on 25 April 2013. Their second daughter, Sofia, was born on 2 October 2017. Modrić generally maintains a low profile outside of football. In addition to his native Croatian, Modrić also speaks English, and Spanish, and is Roman Catholic.  In late 2019, Modrić released his autobiography "Moja igra" ("My Game"), co-written by a prominent Croatian sports journalist Robert Matteoni.

Legal issues.

In March 2018, in an embezzlement and tax evasion trial against the former Dinamo Zagreb executive, Zdravko Mamić, Modrić was called as a witness. Throughout the mid-late 2000s, Modrić signed multiple contracts with Mamić to play at Dinamo Zagreb. Modrić annexed most of his Tottenham transfer fee to Mamić because he was the broker of the move and gave Modrić financial backing early on in his career. Despite stating in 2017 that he signed the annexe clause of the contract ten years earlier, in his testimony he stated

Honours.

Club.

Dinamo Zagreb

International.

Individual.

International

Luka Modrić (; born 9 September 1985) is a Croatian professional footballer who plays as a midfielder for Spanish club Real Madrid and captains the Croatia national team. He plays mainly as a central midfielder, but can also play as an attacking midfielder or as a defensive midfielder, usually deployed as a deep-lying playmaker. He is widely regarded as one of the best midfielders of his generation, and the greatest Croatian footballer of all-time.

Luka Modrić (* 9. září 1985, Zadar, SFR Jugoslávie) je chorvatský fotbalový záložník a reprezentant, který v současnosti hraje za španělský prvoligový klub Real Madrid, kam přestoupil z anglického Tottenhamu. V roce 2007 vyhlášen nejlepším hráčem první chorvatské ligy. Vyniká hlavně v driblingu a v kolmých přihrávkách dopředu. Modrić je stříbrným medailistou z Mistrovství světa 2018. V roce 2018 poprvé po deseti letech sesadil z nadvlády Ronalda a Messiho v anketě Zlatý míč (potažmo Zlatý míč FIFA). Ve stejném roce také obdržel ocenění UEFA fotbalista roku.


Music career.

Tägtgren started playing drums at the age of nine and later learned to play guitar, bass and keyboard.  After Tägtgren's first band Conquest disbanded, he emigrated to the United States. There he became part of the death metal scene after participating in practice sessions with Malevolent Creation's guitarist, Phil Fasciana.  Tägtgren moved back to Sweden and formed the band Hypocrisy. He then signed a recording contract with the independent record label Nuclear Blast.  Although Hypocrisy is his main focus, he has also worked on many other Swedish metal projects. These include PAIN (industrial metal), for which he performs all instruments and vocals and composes all songs, Lock Up (grindcore/death metal), in which he was the vocalist, The Abyss (black metal), where he performed drums, bass and vocals, War (black metal), where he performed drums, and most recently Bloodbath (death metal), also with him on vocals. He has also appeared as a live guitarist for the bands Marduk and E-Type.  Additionally, Peter Tägtgren is a record producer, running "The Abyss" studio where he mixes and edits works of other Scandinavian bands including Sabaton, Dimmu Borgir, Immortal, Amon Amarth, Skyfire, Finnish bands Children of Bodom and Amorphis, and Swiss band Celtic Frost. In 2015 he co-founded the industrial metal band Lindemann with Rammstein lead singer Till Lindemann.  In an interview with Noizr Zine, Peter Tägtgren reported that he's working on new material together with his son Sebastian: "And now, since January, we are sitting in the studio, writing music, and we have like 20 songs or something like that. We don’t know what it is for. It’s not for Hypocrisy, it’s not for Pain, it’s for something else. We don’t know yet, we're just writing because we really have a good time writing."

Personal life.

A year before the recording of his album "Dancing with the Dead (PAIN)", his heart stopped beating for two minutes. This event inspired him to write the album "Dancing with the Dead." Peter is also known as "Mayor of Parlby" as he owns the small village in which he resides (population ~120 people). Peter has been married twice; however, neither marriage lasted. He was quoted as saying, “And my passion for music? It’s hard to be in two places at the same time, and women come and women go. Music stays.”

Alf Peter Tägtgren (born 3 June 1970) is a Swedish musician, multi-instrumentalist and producer. He is the founder, main songwriter, lead vocalist, and guitarist of the death metal band Hypocrisy as well as the industrial metal band PAIN in which he is the only member. He is also the owner of "The Abyss" recording studio. He is also the co-founder of Lindemann, the music project between Tägtgren and Rammstein vocalist, Till Lindemann.

Peter Tägtgren (* 3. června 1970) je jeden z nejrespektovanějších švédských hudebníků. Známý je jako zakladatel, hlavní zpěvák, skladatel a kytarista švédské deathmetalové skupiny Hypocrisy a industrialmetalové skupiny Pain.


Education and early career.

Born in Kampala, Binaisa was initially a lawyer. He was educated at King's College Budo and Makerere College. He then earned a LLB in law from King's College London in 1955 and was called to the Bar at Lincoln's Inn in 1956. He was appointed a Queen's counsel (QC) and had a private law practice in Kampala.  Binaisa was a member of the political parties Uganda National Congress and United Congress Party during the 1950s. He later joined Uganda People's Congress which in 1962 formed the first post-independence government of Uganda. He was appointed the Attorney General in 1962, a position in which he served until 1968, when he resigned over disagreements with President Milton Obote concerning constitutional matters, particularly the presidential powers of detention.  In 1969 Binaisa went into private legal practice, and after Idi Amin took power in 1971, he went into exile first to the United Kingdom where in London he was employed by the London office Graham and James, an international maritime law firm. Following that he came to the United States, where he served as a "paralegal" at the main office of Graham and James in San Francisco. After his presidency ended he returned to London for a time and then ultimately practised law in Mount Vernon, New York. While in the US, he became a member of Uganda Freedom Union, one of several anti-Amin groups in exile.

The presidency.

Following the overthrow of Idi Amin in 1979, Binaisa returned to Uganda. After Idi Amin, Yusuf Lule served as the interim president for 68 days. On 20 June 1979, Binaisa was appointed President of Uganda by the National Consultative Commission, which was then the supreme governing body of the Uganda National Liberation Front (UNLF), a coalition of former Ugandan exiles who had helped remove Idi Amin.  When Binaisa removed the army Chief of Staff, Brigadier Oyite Ojok, he was himself removed from office on 12 May 1980 by the Military Commission, a powerful organ of the UNLF headed by Paulo Muwanga, and whose deputy was Yoweri Museveni (then leader of Uganda Patriotic Movement and the current president of Uganda (1986-to date)). The country was then led by the Presidential Commission of Uganda (set up a few days after the coup) with among others Paulo Muwanga, Yoweri Museveni, Oyite Ojok and Tito Okello.  The Presidential Commission ruled Uganda until the December 1980 general elections. Binaisa had joined, and was made vice president of the Uganda Patriotic Movement. The elections were won by Milton Obote's Uganda Peoples Congress, however, the results were disputed, leading Museveni to launch a guerrilla rebellion, which subsequently led him to gain the presidency in 1986.  The development of the "Movement" political system previously used by Museveni's government has often been attributed to Binaisa. Calling the ideology "Umbrella", Binaisa used the system to consolidate his position during his own presidency, seeking to unite all Ugandans in the same political fold.  Throughout the early 1980s and 1990s, Binaisa lived in New York practicing law and later returned to Uganda, where he led a quiet life in retirement. He was the only former president of Uganda being looked after by the state under provisions of the Constitution of Uganda.

Wedding.

Binaisa married Tomoko Yamamoto on 26 July 2004 in a Unification Church Blessing Ceremony. They met through the internet. The marriage ended in July 2005.

Death.

Binaisa died in his sleep on 5 August 2010. He was 90 years old and had suffered a stroke or heart attack earlier in the year. Someone tried to rouse him for a morning shower but he had died in the night. Binaisa was granted a state funeral.

Godfrey Lukongwa Binaisa QC (30 May 1920 – 5 August 2010) was a Ugandan lawyer who was Attorney General of Uganda from 1962 to 1968 and later served as President of Uganda from June 1979 to May 1980. At his death he was Uganda's only surviving former president.

Godfrey Lukongwa Binaisa (30. května 1920 – 5. srpna 2010) byl ugandský politik a v letech 1979–1980 zastával funkci prezidenta Ugandy. Zemřel ve spánku na srdeční infarkt ve věku 90 let dne 5. srpna 2010. Dostalo se mu cti státního pohřbu.


Features.

The phone supports MicroSD cards up to 2 GB (4 GB with the 6300i variant), meaning that the phone can be used practically as an MP3 player. Using the supplied and freely available Nokia PC Suite, one can convert all the MP3 files in a music library to e-AAC in order to fit more on the card. The 2.5 mm headphone jack means that few commercial headsets will fit the phone, however there are adapters available enabling the use of headphones with a standard jack.  Like most other new Nokia phones, the 6300 eschews their old Pop-Port connector for a standard mini-USB connector. At the launch many questioned why to include the USB port for data, but not for charging. Nokia's support for USB was desired, but slipped to a later release.  The phone also has two slow flashing lights on the side, to show missed calls or messages. This feature is an update of the reminder light in the 6060 fold phone that did not have an external display  With firmware version 06.01 and later, Nokia 6300 is capable of playing MPEG-4 (*.mp4) files with a QCIF resolution of 176*144 at 25 frames per second. The phone allows the user to view the video clips in full-screen landscape mode and set the fast-forward/rewind interval from a few seconds to minutes. Improved audio quality for music playback was also noted for this firmware version, thus making the Nokia 6300 a music phone similar to its counterparts, the Nokia XpressMusic. In addition, video clips can replace ringtones so that an actual motion picture is shown while there is an incoming call.

Popularity and reception.

Nokia 6300 was a highly popular mobile phone handset throughout the world, officially the best-selling Nokia handset in 2007. A report from "The Economist" said that Nokia 6300 was the most popular handset in Africa as of the beginning of 2011, four years after the original release.  Reviewers of the handset generally praised the build quality and feature set. Reviewer "S21" called it "our favourite Nokia phone for a long time", praising the user friendliness and metallic design.  The 6300 was succeeded by the Nokia 6303 classic and Nokia 6700 classic.

Nokia 6300i.

The Nokia 6300i is an upgraded version of the Nokia 6300 with the same design but adding Wireless LAN and VoIP capability and support for 4GB microSD cards (the 6300 could only support up to 2GB microSD cards). It was announced on 26 March 2008. The device is designed for typical use in Europe and only distributed there.

The Nokia 6300 is a mobile telephone handset produced by Nokia. It was announced on 28 November 2006 and released in January 2007. This model was assembled in several factories, including Jucu plant, near Cluj, in Romania.

Nokia 6300 je středně velký, lehký mobilní telefon disponující bohatou výbavou. Pravděpodobně díky svému designu patří k nejprodávanějším mobilním telefonům na světě. Jeho oficiální představení proběhlo v listopadu 2006. Výroba byla zastavena až v polovině roku 2014, po převzetí mobilní divize Nokia, Microsoftem.


History.

Salaspils is one of the oldest settlements in Latvia. Archaeological excavations of 1964–1975 (during the construction of Riga HES) in ancient settlements, burial grounds and castle mounds give evidence of very dense population of the region. At this time, the remains of 11,000-year-old reindeer hunters were found (the oldest known human settlement in all of Latvia) and 3500-year-old remains of Baltic hunters, buried in hollowed-out oak-tree trunks, were found as well. There is evidence that both Livs and Balts built hill forts in the region.  At the end of the 12th century, German merchants travelled up the Daugava, establishing missionaries among the Livonian settlements. One important centre of Daugava Livonians, the small island Mārtiņsala (German:"Kircholm") had a Christian church as early as 1186. So began the Christianizing and gradual subjection of the local Livonian tribes. In 1206, in the early phases of the Livonian Crusade, the Livonian chieftain Ako organized the first revolt against the German crusaders but suffered defeat.  The Latvian name of the Salaspils "island castle" is probably derived from Mārtiņsala Island castle, but the Germanized name Kircholm – from the Mārtiņsala Island church. Both names were used when referring to the territory on the northern bank of the Daugava.  In 1380 the Livonian Order built the castle (Neu-Kircholm) on the mainland, with St George's church by it. The castle was an important support-point outside of Riga, and a small town grew up around it. Both the castle and village were destroyed in 1577 during the Livonian War.  In 1605 the village was a site of the Battle of Kircholm in which forces of the Polish–Lithuanian Commonwealth defeated a much more numerous army of Sweden. This was the biggest battle of the Polish–Swedish War. The battle took place near St George's church and about 9000 Swedish soldiers were buried there. Two memorial stones in Salaspils commemorate of one of the biggest battles in Europe in the 17th century – in memory of the victory of the Polish–Lithuanian forces. Up to the second part of the 20th century a magnificent 17th century military fortification near the Daugava – the Swedish rampart. The destroyed church was renovated in 1631, but later – in 1896 and 1923 - rebuilt.  In the 17th–19th century the surrounding area of Salaspils was governed by the Salaspils Estate which, was established near the destroyed Order's castle and was a part of Riga since 1630, and the Kurtes Estate which was situated in the territory of present Līvzemes street in Salaspils.  The Riga–Daugavpils railway opened in 1861, and the new center of the town developed near Salaspils station just opposite the Kurtes Estate. In the second part of the 19th century, military summer camps were organized in the territory of Salaspils and an Orthodox church was built into a garrison. During the World War I, the front line was at Salaspils for two years, and many of the buildings and farmsteads, especially along the river, were destroyed. The infamous battles at Nāves Sala and Mazā Jugla were fought nearby.  During the first Republic of Latvia there were three parishes in Salaspils territory – Stopiņi, Salaspils (Ķesterciems) and Dole.

World War II.

During World War II, the Nazis established the largest civilian concentration camp in the Baltic states 2 km outside of the town. The Latvian historian Heinrihs Strods and the German Holocaust historians Andrej Angrick and Peter Klein conclude number of deaths at Salaspils was 2,000–3,000 in total, including children. At the site of camp, a major monument complex in remembrance of the Soviet victims of Nazism was opened on 31 October 1967.  There were also two camps for Soviet prisoners of war near Salaspils ("Zweiglager-1" and "Zweiglager-2") both part of "". The exact numbers of those who died at these two camps is the subject of ongoing debate but is nowadays estimated about 1000.  Numbers mentioned by Soviet historians that over 100,000 people were killed in Salaspils during the German occupation are nowadays classified as propaganda, as well as modern Russian controversial book "Latvia Under The Yoke of Nazism", which, according to Latvian historian Aivars Stranga is reviving Soviet-era myths that are long since deconstructed by Holocaust researchers.

City growth in the 1950s and 1960s.

During the late 1950s and early 1960s, various industrial enterprises and governmental institutions developed in Salaspils, such as the nuclear plant and four branches of the Academy of Science. Large multi-storied housing blocks appeared to house incoming power plant workers, many of whom were Russians. In a few decades Salaspils transformed from a very peaceful rural settlement to a mikroraion-style town. Due to the rapid development, Soviet authorities ordered construction of the Riga HES and Riga TEC-2. The dam created a massive reservoir that flooded monuments of Salaspils ancient history. The last unsubmerged sections of old Salaspils have been preserved at Salaspils railway station.

Demographics.

Due to the industrial development of Salaspils, the population has reached 21,000. At the 2000 census, 42% of population was Latvian, 42% was Russian and 16% belonged to other ethnic groups.

Geography.

The National Botanical Gardens.

The National Botanic Garden of Latvia occupy circa 130 ha in the northern part of Salaspils. The National Botanical Garden is famous for having the richest plant collection in the Baltic States. The gardens are open to visitors, and used for recreation by the inhabitants of Salaspils.

Nuclear reactor.

The reactor site is located in the forest, to the west of the Institute of Physics, in the northeastern part of the town. The reactor was operational from 1969 to 1998. The plant partook in neutron activation analysis and gamma irradiation for various materials. It was a pool-type reactor. It is now being demolished.

Notable people.

Notable people born in Salaspils include Acco, Arvīds Ulme, Vilhelms Taurītis, Raitis Ivanāns, Raimonds Nikoluškins, Rudīte Ķikuste, Olga Immermanis, Werner Robert Waldhauer, Maksimilāns Robežgruntnieks, Xaver Marnitz, Johnyboy

Twin towns — sister cities.

Salaspils is twinned with:

Salaspils (;,, ) is a town in Latvia, the administrative centre of Salaspils Municipality. The town is situated on the northern bank of the Daugava river, 18 kilometers to the south-east of the city of Riga.

Salaspils () je město v Lotyšsku poblíž Rigy. Leží na řece Daugavě, konkrétně u přehrady Rīgas HES. Město má zhruba 21 000 obyvatel, značný nárůst počtu obyvatelstva zaznamenalo díky panelákové výstavbě ve 20. století.


Development history.

NASA planners invented the term "extravehicular activity" (abbreviated with the acronym EVA) in the early 1960s for the Apollo program to land men on the Moon, because the astronauts would leave the spacecraft to collect lunar material samples and deploy scientific experiments. To support this, and other Apollo objectives, the Gemini program was spun off to develop the capability for astronauts to work outside a two-man Earth orbiting spacecraft. However, the Soviet Union was fiercely competitive in holding the early lead it had gained in crewed spaceflight, so the Soviet Communist Party, led by Nikita Khrushchev, ordered the conversion of its single-pilot Vostok capsule into a two- or three-person craft named Voskhod, in order to compete with Gemini and Apollo. The Soviets were able to launch two Voskhod capsules before U.S. was able to launch its first crewed Gemini.  The Voskhod's avionics required cooling by cabin air to prevent overheating, therefore an airlock was required for the spacewalking cosmonaut to exit and re-enter the cabin while it remained pressurized. By contrast, the Gemini avionics did not require air cooling, allowing the spacewalking astronaut to exit and re-enter the depressurized cabin through an open hatch. Because of this, the American and Soviet space programs developed different definitions for the duration of an EVA. The Soviet (now Russian) definition begins when the outer airlock hatch is open and the cosmonaut is in vacuum. An American EVA began when the astronaut had at least his head outside the spacecraft. The USA has changed its EVA definition since.

First spacewalk.

The first EVA was performed on March 18, 1965, by Soviet cosmonaut Alexei Leonov, who spent 12 minutes and 9 seconds outside the Voskhod 2 spacecraft. Carrying a white metal backpack containing 45 minutes' worth of breathing and pressurization oxygen, Leonov had no means to control his motion other than pulling on his tether. After the flight, he claimed this was easy, but his space suit ballooned from its internal pressure against the vacuum of space, stiffening so much that he could not activate the shutter on his chest-mounted camera.  At the end of his space walk, the suit stiffening caused a more serious problem: Leonov had to re-enter the capsule through the inflatable cloth airlock, in diameter and long. He improperly entered the airlock head-first and got stuck sideways. He could not get back in without reducing the pressure in his suit, risking "the bends". This added another 12 minutes to his time in vacuum, and he was overheated by from the exertion. It would be almost four years before the Soviets tried another EVA. They misrepresented to the press how difficult Leonov found it to work in weightlessness and concealed the problems encountered until after the end of the Cold War.

Project Gemini.

The first American spacewalk was performed on June 3, 1965, by Ed White from the second crewed Gemini flight, Gemini IV, for 21 minutes. White was tethered to the spacecraft, and his oxygen was supplied through a umbilical, which also carried communications and biomedical instrumentation. He was the first to control his motion in space with a Hand-Held Maneuvering Unit, which worked well but only carried enough propellant for 20 seconds. White found his tether useful for limiting his distance from the spacecraft but difficult to use for moving around, contrary to Leonov's claim. However, a defect in the capsule's hatch latching mechanism caused difficulties opening and closing the hatch, which delayed the start of the EVA and put White and his crewmate at risk of not getting back to Earth alive.  No EVAs were planned on the next three Gemini flights. The next EVA was planned to be made by David Scott on Gemini VIII, but that mission had to be aborted due to a critical spacecraft malfunction before the EVA could be conducted. Astronauts on the next three Gemini flights (Eugene Cernan, Michael Collins, and Richard Gordon), performed several EVAs, but none was able to successfully work for long periods outside the spacecraft without tiring and overheating. Cernan attempted but failed to test an Air Force Astronaut Maneuvering Unit which included a self-contained oxygen system.  On November 13, 1966, Edwin "Buzz" Aldrin became the first to successfully work in space without tiring during Gemini XII, the last Gemini mission. Aldrin worked outside the spacecraft for 2 hours and 6 minutes, in addition to two stand-up EVAs in the spacecraft hatch for an additional 3 hours and 24 minutes. Aldrin's interest in scuba diving inspired the use of underwater EVA training to simulate weightlessness, which has been used ever since to allow astronauts to practice techniques of avoiding wasted muscle energy.

First EVA crew transfer.

On January 16, 1969, Soviet cosmonauts Aleksei Yeliseyev and Yevgeny Khrunov transferred from Soyuz 5 to Soyuz 4, which were docked together. This was the second Soviet EVA, and it would be almost another nine years before the Soviets performed their third.

Apollo lunar EVA.

American astronauts Neil Armstrong and Buzz Aldrin performed the first EVA on the lunar surface on July 21, 1969 (UTC), after landing their Apollo 11 Lunar Module spacecraft. This first Moon walk, using self-contained portable life support systems, lasted 2 hours and 36 minutes. A total of fifteen Moon walks were performed among six Apollo crews, including Charles "Pete" Conrad, Alan Bean, Alan Shepard, Edgar Mitchell, David Scott, James Irwin, John Young, Charles Duke, Eugene Cernan, and Harrison "Jack" Schmitt. Cernan was the last Apollo astronaut to step off the surface of the Moon. Apollo 15 command module pilot Al Worden made an EVA on August 5, 1971, on the return trip from the Moon, to retrieve a film and data recording canister from the service module. He was assisted by Lunar Module Pilot James Irwin standing up in the Command Module hatch. This procedure was repeated by Ken Mattingly and Charles Duke on Apollo 16, and by Ronald Evans and Harrison Schmitt on Apollo 17.

Post-Apollo EVAs.

The first EVA repairs of a spacecraft were made by Charles "Pete" Conrad, Joseph Kerwin, and Paul J. Weitz on May 26, June 7, and June 19, 1973, on the Skylab 2 mission. They rescued the functionality of the launch-damaged Skylab space station by freeing a stuck solar panel, deploying a solar heating shield, and freeing a stuck circuit breaker relay. The Skylab 2 crew made three EVAs, and a total of ten EVAs were made by the three Skylab crews. They found that activities in weightlessness required about 2 times longer than on Earth because many astronauts suffered spacesickness early in their flights.  After Skylab, no more EVAs were made by the United States until the advent of the Space Shuttle program in the early 1980s. In this period, the Soviets resumed EVAs, making four from the Salyut 6 and Salyut 7 space stations between December 20, 1977, and July 30, 1982.  When the United States resumed EVAs on April 7, 1983, astronauts started using an Extravehicular Mobility Unit (EMU) for self-contained life support independent of the spacecraft. STS-6 was the first Space Shuttle mission during which a spacewalk was conducted. Also, for the first time, American astronauts used an airlock to enter and exit the spacecraft like the Soviets. Accordingly, the American definition of EVA start time was redefined to when the astronaut switches the EMU to battery power.

Chinese EVA.

China became the third country to independently carry out an EVA on September 27, 2008 during the Shenzhou 7 mission. Chinese astronaut Zhai Zhigang completed a spacewalk wearing the Chinese-developed Feitian space suit, with astronaut Liu Boming wearing the Russian-derived Orlan space suit to help him. Zhai completely exited the craft, while Liu stood by at the airlock, straddling the portal.

Commemoration.

The first spacewalk, made by Soviet cosmonaut Alexei Leonov, was commemorated in 1965 with several Eastern Bloc stamps (see Alexei Leonov#Stamps). Since the Soviet Union did not publish details of the Voskhod spacecraft at the time, the spaceship depiction in the stamps was purely fictional.  The U.S. Post Office issued a postage stamp in 1967 commemorating Ed White's first American spacewalk. The engraved image has an accurate depiction of the Gemini IV spacecraft and White's space suit.

Designations.

NASA "spacewalkers" during the Space Shuttle program were designated as EV-1, EV-2, EV-3 and EV-4 (assigned to mission specialists for each mission, if applicable).

Camp-out procedure.

For EVAs from the International Space Station, NASA employed a "camp-out" procedure to reduce the risk of decompression sickness. This was first tested by the Expedition 12 crew. During a camp out, astronauts sleep overnight in the airlock prior to an EVA, lowering the air pressure to, compared to the normal station pressure of. Spending a night at the lower air pressure helps flush nitrogen from the body, thereby preventing "the bends". More recently astronauts have been using the In-Suit Light Exercise protocol rather than camp-out to prevent decompression sickness.

Extravehicular activity (EVA) is any activity done by an astronaut or cosmonaut outside a spacecraft beyond the Earth's appreciable atmosphere. The term most commonly applies to a spacewalk made outside a craft orbiting Earth (such as the International Space Station). On March 18, 1965, Alexei Leonov became the first human to perform a spacewalk, exiting the capsule during the Voskhod 2 mission for 12 minutes and 9 seconds. The term also applied to lunar surface exploration (commonly known as moonwalks) performed by six pairs of American astronauts in the Apollo program from 1969 to 1972. On July 21, 1969, Neil Armstrong became the first human to perform a moonwalk, outside his lunar lander on Apollo 11 for 2 hours and 31 minutes. On the last three Moon missions astronauts also performed deep-space EVAs on the return to Earth, to retrieve film canisters from the outside of the spacecraft. Astronauts Pete Conrad, Joseph Kerwin, and Paul Weitz also used EVA in 1973 to repair launch damage to Skylab, the United States' first space station.

Výstup do vesmíru (, zkratka EVA) označuje souhrnně veškeré činnosti kosmonautů, které se provádějí mimo kosmickou loď. Jedná se především o venkovní práce na kosmických stanicích.


Versus cytokines.

"Growth factor" is sometimes used interchangeably among scientists with the term "cytokine." Historically, cytokines were associated with hematopoietic (blood and lymph forming) cells and immune system cells (e.g., lymphocytes and tissue cells from spleen, thymus, and lymph nodes). For the circulatory system and bone marrow in which cells can occur in a liquid suspension and not bound up in solid tissue, it makes sense for them to communicate by soluble, circulating protein molecules. However, as different lines of research converged, it became clear that some of the same signaling proteins which the hematopoietic and immune systems use were also being used by all sorts of other cells and tissues, during development and in the mature organism.  While "growth factor" implies a positive effect on cell division, "cytokine" is a neutral term with respect to whether a molecule affects proliferation. While some cytokines can be growth factors, such as G-CSF and GM-CSF, others have an inhibitory effect on cell growth or proliferation. Some cytokines, such as Fas ligand, are used as "death" signals; they cause target cells to undergo programmed cell death or "apoptosis".  The growth factor was first discovered by Rita Levi-Montalcini, which won her a Nobel Prize in Physiology or Medicine.

Classes.

Individual growth factor proteins tend to occur as members of larger families of structurally and evolutionarily related proteins. There are many families, some of which are listed below:

In platelets.

The alpha granules in blood platelets contain growth factors PDGF, IGF-1, EGF, and TGF-β which begin healing of wounds by attracting and activating macrophages, fibroblasts, and endothelial cells.

Uses in medicine.

For the last two decades, growth factors have been increasingly used in the treatment of hematologic and oncologic diseases and cardiovascular diseasessuch as:

A growth factor is a naturally occurring substance capable of stimulating cellular growth, proliferation, healing, and cellular differentiation. Usually it is a protein or a steroid hormone. Growth factors are important for regulating a variety of cellular processes.

Růstový faktor je obecně látka nebo podnět, které navozují růst organismu nebo jeho části. V praxi se mezi růstové faktory řadí především skupina proteinů, které stimulují buněčnou proliferaci a diferenciaci. Zpravidla se růstové faktory účastní signalizace mezi buňkami.