Specific activity

Specific activity is the activity per quantity of a radionuclide and is a physical property of that radionuclide.
Activity is a quantity (for which the SI unit is the becquerel) related to radioactivity. The becquerel (Bq) is defined as the number of radioactive transformations per second that occur in a particular radionuclide. The older, non-SI unit of activity is the curie (Ci), which is transformations per second.
Since the probability of radioactive decay for a given radionuclide is a fixed physical quantity (with some slight exceptions, see changing decay rates), the number of decays that occur in a given time of a specific number of atoms of that radionuclide is also a fixed physical quantity (if there are large enough numbers of atoms to ignore statistical fluctuations).
Thus, specific activity is defined as the activity per quantity of atoms of a particular radionuclide. It is usually given in units of Bq/kg, but another commonly used unit of activity is the curie (Ci) allowing the definition of specific activity in Ci/g. The amount of specific activity should not be confused with level of exposure to ionizing radiation and thus the exposure or absorbed dose. The absorbed dose is the quantity important in assessing the effects of ionizing radiation on humans.
Formulation.
Relationship between "λ" and T1/2.
Radioactivity is expressed as the decay rate of a particular radionuclide with decay constant "λ" and the number of atoms "N":
The integral solution is described by exponential decay:
where "N"0 is the initial quantity of atoms at time "t" = 0.
Half-life T1/2 is defined as the length of time for half of a given quantity of radioactive atoms to undergo radioactive decay:
Taking the natural logarithm of both sides, the half-life is given by
Conversely, the decay constant "λ" can be derived from the half-life "T"1/2 as
Calculation of specific activity.
The mass of the radionuclide is given by
where "M" is molar mass of the radionuclide, and "N"A is the Avogadro constant. Practically, the mass number "A" of the radionuclide is within a fraction of 1% of the molar mass expressed in g/mol and can be used as an approximation.
Specific radioactivity "a" is defined as radioactivity per unit mass of the radionuclide:
Thus, specific radioactivity can also be described by
This equation is simplified to
When the unit of half-life is in years instead of seconds:
Example: specific activity of Ra-226.
For example, specific radioactivity of radium-226 with a half-life of 1600 years is obtained as
This value derived from radium-226 was defined as unit of radioactivity known as the curie (Ci).
Calculation of half-life from specific activity.
Experimentally measured specific activity can be used to calculate the half-life of a radionuclide.
Where decay constant "λ" is related to specific radioactivity "a" by the following equation:
Therefore, the half-life can also be described by
Example: half-life of Rb-87.
One gram of rubidium-87 and a radioactivity count rate that, after taking solid angle effects into account, is consistent with a decay rate of 3200 decays per second corresponds to a specific activity of . Rubidium atomic mass is 87 g/mol, so one gram is 1/87 of a mole. Plugging in the numbers:
Applications.
The specific activity of radionuclides is particularly relevant when it comes to select them for production for therapeutic pharmaceuticals, as well as for immunoassays or other diagnostic procedures, or assessing radioactivity in certain environments, among several other biomedical applications.


Fresnel number

The Fresnel number ("F"), named after the physicist Augustin-Jean Fresnel, is a dimensionless number occurring in optics, in particular in scalar diffraction theory.
For an electromagnetic wave passing through an aperture and hitting a screen, the Fresnel number "F" is defined as
where
The Fresnel number is a useful concept in physical optics. Conceptually, it is the number of half-period zones in the wavefront amplitude, counted from the center to the edge of the aperture, as seen from the observation point (the center of the imaging screen), where a half-period zone is defined so that the wavefront phase changes by formula_5 when moving from one half-period zone to the next.
An equivalent definition is that the Fresnel number is the difference, expressed in half-wavelengths, between the "slant" distance from the observation point to the "edge" of the aperture and the "orthogonal" distance from the observation point to the "center" of the aperture.
The Fresnel number establishes a coarse criterion to define the near and far field approximations.
Essentially, if Fresnel number is small – less than roughly 1 – the beam is said to be in the "far field". If Fresnel number is larger than 1, the beam is said to be "near field". However this criterion does not depend on any actual measurement of the wavefront properties at the observation point.
Another criterion called "Gaussian pilot beam" allowing to define far and near field conditions, consists to measure the actual wavefront surface curvature for an unaberrated system. In this case the wavefront is planar at the aperture position, when the beam is collimated, or at its focus when the beam is converging/diverging. In detail, within a certain distance from the aperture – "the near field" – the amount of wavefront curvature is low. Outside this distance – " the far field " – the amount of wavefront curvature is high. This concept applies equivalently close to the focus.
According to the user manual for the Zemax optical design software, the correct approximation for propagation in the near field follows the angular spectrum method. This approximation works well when at the observation point the distance to the aperture is of the same order as the aperture size. This propagation regime satisfies formula_6.
The correct approximation for the propagation in the near field is Fresnel diffraction. This approximation works well when at the observation point the distance to the aperture is bigger than the aperture size. This propagation regime verifies formula_7.
Finally, once at the observation point the distance to the aperture is much bigger than the aperture size, propagation becomes well described by Fraunhofer diffraction. This propagation regime verifies formula_8.
The Gaussian pilot beam.
This criterion, firstly described by and now adopted in propagation codes like, allows one to determine the realm of application of near and far field approximations taking into account the actual wavefront surface shape at the observation point, to sample its phase without aliasing. This criterion is named "Gaussian pilot beam" and fixes the best propagation method (among angular spectrum, Fresnel and Fraunhofer diffraction) by looking at the behavior of a Gaussian beam
piloted from the aperture position and the observation position.
Near/far field approximations are fixed by the analytical calculation of the Gaussian beam Rayleigh length and by its comparison with the input/output propagation distance. If the ratio between input/output propagation distance and Rayleigh length returns formula_9 the surface wavefront maintains itself nearly flat along its path, which means that no sampling rescaling is requested for the phase measurement. In this case the beam is said to be near field at the observation point and angular spectrum method is adopted for the propagation. At contrary, once the ratio between input/output propagation distance and Gaussian pilot beam Rayleigh range returns formula_10 the surface wavefront gets curvature along the path. In this case a rescaling of the sampling is mandatory for a measurement of the phase preventing aliasing. The beam is said to be far field at the observation point and Fresnel diffraction is adopted for the propagation. Fraunhofer diffraction returns then to be an asymptotic case that applies only when the input/output propagation distance is large enough to consider the quadratic phase term, within the Fresnel diffraction integral, negligible irrespectively to the actual curvature of the wavefront at the observation point.
As the figures explain, the Gaussian pilot beam criterion allows describing the diffractive propagation for all the near/far field approximation cases set by the coarse criterion based on Fresnel number.


Just minor semitone


Beyonders

The Beyonders are a fictional enigmatic higher-dimensional race appearing in American comic books published by Marvel Comics.
Publication history.
The Beyonders were first mentioned in the team-up comic "Marvel Two-in-One" #63 (May 1980), by Mark Gruenwald and Jerry Bingham.
The Beyonders received an entry in the "Official Handbook of the Marvel Universe Update '89" #1. They also received an entry in "Secret Wars Official Guide to the Marvel Multiverse".
An initially unrelated character called the Beyonder was tied to these older characters by Steve Englehart for his "Secret Wars III" story in "Fantastic Four" #318-319 (September–October 1988). The Beyonder first appeared during the first Secret Wars, as a being that was stated to be the omnipotent embodiment of an entire separated multiverse. As he became self-aware, he recognized himself as the only person in his Universe. According to Englehart, an editor hated the character and ordered the Beyonder "removed" from the Marvel Universe. Englehart did as asked but has stated that he tried to exile the character with dignity. The character was retconned into a less powerful character, a self-aware Cosmic Cube inhabiting his own "dimension" because there was no matrix to hold his energy, with the explanation that other more powerful beings had exercised their powers on the Beyonder's behalf to ease his transition into self-awareness. The Beyonder later underwent another retcon, briefly becoming a mutant inhuman, and after a last retcon is now considered to be a member of the alien race of the same name and is referred to as a "child unit" by the Beyonders.
Fictional history.
The Beyonders are a race of extra-dimensional entities powerful enough to collect planets. Their nature is so alien that they are unable to leave their own dimension and for millennia were never observed by any being of the Earth dimension (apparently including even the near-omniscient Watchers themselves); to interact with the Earth dimension they must operate through agents. After becoming aware of the Earth, the Beyonders began studying the Marvel Multiverse with amusement and curiosity. They first came to the attention of Earthlings when they commissioned the alien Nuwali race to create the Savage Land as part of their study of evolution. Thousands of years later, the Beyonders created the Fortisquians as agents to observe other worlds, including Max.
They eventually hired the Pegasusian alien race as agents, to tow Counter-Earth to the Beyonders' museum. When the High Evolutionary discovered the disappearance of Counter-Earth, alongside the Thing, Alicia Masters, Starhawk, Moondragon, and Her, the Evolutionary pursued the Beyonders to rescue his world. When the Evolutionary arrived at the Beyonders' planet museum, he himself reported that his mind snapped when he witnessed the scope of their powers and how effectively insignificant he was compared to these alien beings. It is this encounter that marks the beginning of the High Evolutionary's mental instability.
Every now and then the Beyonders would shunt a modicum of energy to the universe, allowing sentient beings to use them to create Cosmic Cubes—a practice they appear to have given up after the admonishments by Eternity and the Living Tribunal regarding the disruptive effect of these actions. One of these energy modicums would later develop sentience and take its name after its creators, the Beyonder.
Time Runs Out.
When entire universes throughout the Multiverse began to collide with each other, with each universe's respective Earth being the points of impact—events known as "incursions"—the Avengers send Hank Pym to find answers at the start of the "Time Runs Out" storyline. Instead, he learns the incursions are being caused by the Beyonders, whom he also refers to as the Ivory Kings. Upon returning to Earth, he tells his fellow heroes that the Beyonders have killed the Living Tribunal along with all the Celestials, and every abstract entity (including Eternity, Infinity, Lord Chaos, Master Order, and the In-Betweener) as part of an experiment involving the destruction of all life throughout the Marvel Multiverse. Later, Rabum Alal reveals to Doctor Strange that the Beyonders are responsible for the accident that turned Owen Reece into the Molecule Man, the same accident that created the sentient energy modicum that would name itself "The Beyonder" after its creators. They created the Molecule Man as a singularity—identical in every reality—to function as a "bomb" that would destroy its native universe. The purpose of their experiment was to eventually kill all of the Molecule Men at the same time, bringing an end to the multiverse. After discovering that they are unable to travel through time since they are constrained and restricted to their own sequential timeline, Doom, Strange and Molecule Man confront the Beyonders one last time. Their attack apparently failed and as a result the number of universes was reduced from thousands to barely more than two dozen. However, it was later revealed the attack had actually been a success, and that Doom used his own bomb made of Molecule Men from throughout the Multiverse, which not only allowed him to destroy the Beyonders but at the same time channel the resulting energy into Owen Reece, and use that energy to collect what remained of the Multiverse into a single planet known as Battleworld.
A number of survivors of the Multiverse were collected on Battleworld under the reign of the now-cosmically powered "God Emperor" Doom - their memories altered to become the lords and ladies of various factions of a medieval new order. The arrival of a handful of other survivors who recalled the truth shattered this illusion and began the conflict that would lead to the Multiverse's recreation.
Powers and abilities.
The Beyonders have been witnessed killing all of the Celestials in the Marvel multiverse at the same time, destroying abstract entities such as Eternity and Infinity, and three members of the race together managed to kill the Living Tribunal itself.
The Beyonders are what Doctor Doom calls "linear beings". Despite their vast powers and knowledge, they seem unable to travel forward or backward in time. They have also displayed other limitations, as an explosion strong enough to destroy a few thousand universes was sufficient to kill them.


Iowa Tests of Educational Development

The Iowa Tests of Educational Development (ITED) are a set of standardized tests given annually to high school students in many schools in the United States, covering Grades 9 to 12. The tests were created by the University of Iowa's College of Education in 1942, as part of a program to develop a series of nationally accepted standardized achievement tests.
The primary goal of the ITED is to provide information to assist educators in improving teaching.
Goals of the ITED.
Rather than testing a student's content knowledge, the ITED endeavors to evaluate students' skills in a variety of areas, especially based on problem solving and critical analysis of texts. These are considered by the authors of the ITED to be skills acquired across multiple curricular areas and skills that are important for academic success. Within the skill areas evaluated by the ITED, the test is designed to elicit information about a student's current skill level, growth and abilities within each area tested. The ITED is designed to examine and compare a student's ability in several educational fields, including vocabulary, reading comprehension, language, spelling, mathematical concepts and problem solving, computation, analysis of social studies materials, analysis of science materials, and use of sources. Although the test is broken up into these fields, the goal of the ITED is to track the development of the skills and analysis needed in each of these areas rather than the content.
ITED Sections.
Vocabulary.
The vocabulary section of the ITED focuses on testing the development of students' vocabulary for everyday communication.
Reading Comprehension.
The reading comprehension section of the ITED tests literal understanding as well as the higher-level skills of inference and analysis.
Language: Revising Written Materials.
The language section of the ITED focuses on students' ability to revise and edit texts, include issues of style and clarity as well as grammatical errors.
Spelling.
The ITED spelling test presents students with groups of words; students must indicate which word is misspelled or whether they are all spelled correctly.
Mathematics: Concepts and Problem Solving.
This section focuses on problem solving and logical thinking skills rather than mathematical computation. Some questions require basic computation while others require students to determine the steps necessary to solve a problem without actually completing the problem itself.
Analysis of Social Studies Materials.
This ITED section requires students to analyze information presented to them and will often contain documents including maps, graphs and reading passages.
Analysis of Science Materials.
The science materials section of the ITED evaluates students' familiarity and comfort with scientific procedures and their ability to understand and analyze scientific information and methods.
Sources of Information.
The sources of information section tests students' ability to do research and to use the resources available to them to find information.
Uses of the ITED.
The ITED is used in the majority of schools in the state of Iowa, both in the public and private education sectors, and the tests have found some use in other regions of the United States. The ITED is administered in the fall and results are used along with classroom observation and student work by teachers to evaluate the progress of a student's abilities. The ITED results are also used by the state of Iowa to monitor schools' progress and determine if schools and students are meeting goals.
Individual student ITED results are used to help determine placements and tracks. The ITED helps educators and students plan student schedules by providing information for the school to use in placing students in classes of varying levels of difficulty. The results also provide information about students' academic potential, assisting students and school advisors as they make their high school course selections and plan for college.
The ITED is scored based on the number of questions a student answered correctly. Research has indicated that there is a correlation between ITED scores and student grade point averages (GPAs), although these correlations were lower than expected and lower than indicated by prior research.


Common Educational Proficiency Assessment

Common Educational Proficiency Assessment (CEPA) is a set of locally-developed standardized tests used for admissions and placement by three federal institutions of higher education in the United Arab Emirates (Zayed University, the Higher Colleges of Technology, and UAEU). The tests are produced by the UAE Ministry of Higher Education and Scientific research as part of NAPO (National Admissions and Placement Office) and administered in the three federal institutions. Around 17,000 grade 12 Emirati students take the tests each year.
There are two CEPA exams. CEPA-English tests basic English proficiency, and CEPA-Math measures basic math skills. Both exams are administered in two formats: paper-based (with scanned answer sheets) and computer-based.
Context.
Zayed University, the Higher Colleges of Technology, and UAE University are primarily English-medium universities located in the United Arab Emirates. Each of these institutions has a foundations or academic bridge program designed to help students increase their level of English to the level required for higher education. CEPA scores indicate which, if any, level of English course is necessary.
CEPA-English.
CEPA-English was created in 2002 to place students into English foundations programs at the three federal institutions of higher education in the United Arab Emirates (Zayed University, the Higher Colleges of Technology, and UAE University), all of which are English-medium.
It was designed to discriminate best at the average level of high school students in the UAE. The test takes two hours, in which test-takers complete 110 multiple choice questions and one essay. Test items are developed in conjunction with English teachers at the three institutions, in an effort to keep the content culturally relevant and compatible with local sensibilities.
Grammar and Vocabulary.
CEPA-English tests English Grammar and Vocabulary proficiency using multiple-choice sentence-completion questions. There are 45 grammar questions, which cover a wide range of basic English structures. There are 40 vocabulary questions, testing the most common words of English, drawn from modified word lists, such as the General Service List, as well as academically-oriented words drawn from a modified Academic Word List.
Reading.
The Reading Section of CEPA-English includes one visual, non-linear text (such as an advertisement) and two descriptive, narrative, or expository texts of about 400 words each. Vocabulary level is kept to approximately the first 2000 words. The questions on the Reading Section are all multiple-choice, and test students’ ability to identify the main idea of the text, find simple factual details, identify pronoun references, or make inferences about the text.
Writing.
There is one task on the Writing Section of the exam. Typically, the test-taker is given a prompt eliciting an opinion about a general or local issue. The prompt is given in English and Arabic, and topics vary across versions. The recommended time for the Writing Section is about 30 minutes, in which the test-taker is expected to produce 150-200 words of original text.
Scoring.
The multiple-choice section of CEPA-English is scored using IRT (Item Response Theory) three parameter modeling. Each test version is linked to previous versions, and new parameters are gathered during large administrations. The raw responses are scored using these parameters. A formula is then applied to convert the resulting numbers into CEPA scores, ranging from 90 to 210.
The Writing Section is double-blind marked by local English teachers from the three federal institutions. The bands range from 0 (blank, no attempt) to 6. The scores are then mediated, employing multi-faceted Rasch measurement. Anomalous scores (e.g. from high rater disagreement) or jagged profiles are reviewed by the exam staff.
Score Descriptors.
CEPA-English provides the following descriptors in its documentation.
CEPA-Math.
CEPA-Math tests basic math skills including algebra, geometry and measurement, basic data analysis and number sense (e.g. scientific notation, order of operations, fractions/decimals and estimation). There are 50 questions on CEPA-Math. Like CEPA-English, the test is developed in conjunction with faculty members at the three federal institutions of higher education, and scored using IRT modeling.
Test Use.
Admissions and cut scores.
All cut scores and placement scores are determined by the three federal institutions of higher education themselves, with cooperation by CEPA staff. According to the website of Ministry of Higher Education and Scientific Research and the universities’ own websites, CEPA cut scores are as follows.
Around 78% of test-takers score above 150, and are eligible for entry into one of the federal institutions. Around 16% achieved a score high enough to bypass foundation programs in 2012, in sharp contrast to the 3% who achieved this score in 2003, when the exam was first used.
Other purposes.
In 2007, CEPA was used as an exit exam for high schools in the UAE Ministry of Education system. CEPA has also been used to identify trends in UAE education and as an indicator of school progress. In 2012, vocational schools such as the Abu Dhabi Vocational Education and Training Institute (ADVETI) began to have their applications processed by NAPO, which will include the use of CEPA scores.
Test Preparation Materials.
The CEPA office has periodically produced materials designed for independent study and test preparation. Among these are CEPA-Learn, a multiple-choice mobile phone app that used SMS to provide students with practice questions, and CEPA Challenge, a study book which has been freely distributed to all grade 12 students since 2008.
See also.
Official website (in English)
Swann, Melanie (22 June 2012) "Hundreds of UAE students face college rejection" "The National" (Retrieved 22 June 2012)


2328 Robeson

2328 Robeson, provisional designation , is a background asteroid from the inner regions of the asteroid belt, approximately in diameter. It was discovered on 19 April 1972, by astronomer Soviet–Russian Tamara Smirnova at the Crimean Astrophysical Observatory in Nauchnij, on the Crimean peninsula. It was named after American actor and singer Paul Robeson. The C/X-type asteroid has a rotation period of 18.6 hours.
Orbit and classification.
"Robeson" is a non-family asteroid from the main belt's background population. It orbits the Sun in the inner main-belt at a distance of 2.0–2.7 AU once every 3 years and 7 months (1,308 days; semi-major axis of 2.34 AU). Its orbit has an eccentricity of 0.15 and an inclination of 10° with respect to the ecliptic. The body's observation arc begins with its official discovery observation at Nauchnij in April 1972.
Physical characteristics.
In the SMASS classification "Robeson" is a carbonaceous C-type asteroid. It has also been characterized as an X-type asteroid by Pan-STARRS photometric survey.
Rotation period.
In December 2006, a rotational lightcurve of "Robeson" was obtained from photometric observations at the Leura and Hunters Hill observatories in Australia. Lightcurve analysis gave a rotation period of 18.632 hours with a brightness amplitude of 0.20 magnitude ().
Diameter and albedo.
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, "Robeson" measures between 11.75 and 13.30 kilometers in diameter and its surface has an albedo between 0.06 and 0.1281.
The "Collaborative Asteroid Lightcurve Link" assumes it to be a stony asteroid with a standard albedo of 0.20 and calculates a diameter of 7.46 kilometers based on an absolute magnitude of 13.0.
Naming.
This minor planet was named after in memory of African-American singer and actor Paul Robeson (1898–1976). The official naming citation was published by the Minor Planet Center on 8 February 1982 ().


Lavalier microphone

A lavalier microphone or lavalier (also known as a lav, lapel mic, clip mic, body mic, collar mic, neck mic or personal mic) is a small microphone used for television, theatre, and public speaking applications in order to allow for hands-free operation. They are most commonly provided with small clips for attaching to collars, ties, or other clothing. The cord may be hidden by clothes and either run to a radio frequency transmitter kept in a pocket or clipped to a belt, or routed directly to the mixer or a recording device.
These miniature microphones are often supplied with a choice of push-on grilles of differing lengths that provide gentle high-frequency boost by forming a resonant cavity. A peak of approximately 6 dB at 6–8 kHz is considered beneficial for compensating loss of clarity when chest-mounted, as is a peak of a few decibels at 10–15 kHz when mounted in the hair above the forehead. This method of boosting high frequencies does not worsen noise performance, as electronic equalization would do.
History.
Lapel microphones date from 1932. Various models were made, including ones with condenser diaphragms, ribbons, moving coils, and carbon buttons. The term referred to any small microphone that could be hooked into the buttonhole of the lapel of a coat. The lapel microphone offered freedom of movement.
The term lavalier originally referred to jewelry in the form of a pendant worn around the neck. Its use as the name of a type of microphone originates from the 1930s, when various practical solutions to microphone use involved hanging the microphone from the neck. For instance, a Dictaphone microphone could be suspended on a cord around the neck in order to retain some degree of freedom of movement while recording one's voice onto a wax cylinder in 1941. Telephone operators and air traffic controllers used microphones that rested on the chest and were secured by a strap around the neck. In the 1950s, some microphone models were designed to be hung on a string around the neck. In 1953, Electro-Voice introduced the Model 647A, a small omnidirectional dynamic microphone fitted with a cord to go around the neck. The body of the 647A was lightweight at and relatively small at in diameter and in length. In 1954, Shure Brothers offered the larger 530 Slendyne, which could be handheld, mounted on a microphone stand, or worn around the neck on a "lavalier cord."
Mounting techniques.
Lavalier microphones are attached differently depending on the nature of their use. In theater applications where the microphone is used to amplify an actor or a singer's voice, lavs are typically concealed in the performer's hair; this placement eliminates the possibility of scratching against their clothing while they move, which would result in the amplification of the scratching sounds as well. It also adds to the suspension of disbelief, since the characters themselves would not be wearing microphones, especially if the plot is set in a time before lavalier microphones existed. Occasionally, specially designed skin-color headsets known as "headworn microphones" are used in stage applications when actors spend a good deal of their performance singing and moving around quickly, such as in stage musicals and in lecture or presentation scenarios. A headworn microphone is essentially a lavalier on a stiff wire mount that loops over the performer's ear.
In television and documentary applications, the lavalier will typically be clipped to an article of the subject's clothing, such as a tie, jacket or collar. In narrative motion picture usage, lavs are almost always hidden under clothing to conceal the fact that the person has a microphone. The boom microphone typically sounds "better" and more natural than a lavalier mic and is always a soundperson's first choice; however, for exterior location shooting, it often may be more practical to use a lavalier. One such situation would be during a wide shot that forces the boom operator to keep a distance from the speaker that isn't close enough to achieve a good signal-to-noise ratio with the microphone. In that instance, a lav mic hidden on the speaker due to its proximity would achieve good signal-to-noise ratio for recording of speech. When lavalier microphones need to be concealed under clothing, the possibility of material scratching against the microphone is a certain risk. To minimize this problem, sound recordists sometimes wrap the head of the microphones in moleskin or place it inside a hollow-centered, column-shaped sponge and place it under a placard, behind a button, or within the knot of a tie.
The transmitter pack to which the microphone is attached may also need to be hidden under a person's clothing. Transmitter pouches are held on with elastic straps and serve to keep the transmitter hidden in various places where clothing provides a non-revealing space, such as high around the waist in the space created at the spine just above the belt line, inside the thigh under a skirt or dress, about the ankles under a pant leg, or even on the inside of a boot.
Academia.
In a 1984 study administered by Cornell University's College of Arts and Sciences, it was found that the use of lavalier microphones in an academic setting was beneficial to the dissemination of information. By allowing a presenter to move freely in a presenting space, the lavalier microphone allows the presenter to offer continuous visual stimulation to the audience, enabling the speaker to hold their attention longer or more easily. Even in smaller applications where the audience contained fewer than 25 attendees, the lack of restrictions on the hands proved to offer similar visual stimulation in capturing and maintaining attention.


Sigma Piscium

Sigma Piscium (Sigma Psc, σ Piscium, σ Psc) is a main-sequence star in the zodiac constellation of Pisces. It has an apparent magnitude of +5.50, meaning it is barely visible to the naked eye, according to the Bortle scale. While parallax measurements by the Hipparcos spacecraft give a distance of approximately 430 light years (133 parsecs), dynamical parallax measurements put it slightly closer, at 368 light-years (113 parsecs) from Earth.
Sigma Piscium is a spectroscopic binary system, meaning the components of the system have been detected from periodic Doppler shifts in their spectra. In this case, light from both stars can be detected and it is double-lined. It has an orbital period of 81 days, and the orbit is relatively eccentric, at about 0.9. Both components are B-type main-sequence stars.
Sigma Piscium is moving through the Milky Way at a speed of 23.5 km/s relative to the Sun. Its projected galactic orbit carries it between 24,300 and 29,400 light years from the center of the galaxy.
Sigma Piscium was a latter designation of 40 Andromedae.
Naming.
In Chinese, (), meaning "Legs", refers to an asterism consisting of σ Piscium, η Andromedae, 65 Piscium, ζ Andromedae, ε Andromedae, δ Andromedae, π Andromedae, ν Andromedae, μ Andromedae, β Andromedae, τ Piscium, 91 Piscium, υ Piscium, φ Piscium, χ Piscium and ψ1 Piscium. Consequently, the Chinese name for σ Piscium itself is (, .)


Ford Gyron

The Ford Gyron was a futuristic two-wheeled gyrocar first shown to the world in 1961 at the Detroit Motor Show as a concept car designed by Syd Mead. One wheel was at the front and the other at the rear like a motorcycle and the car was stabilized by gyroscopes. The two occupants of the vehicle were seated side by side and, when the vehicle was stationary, two small legs appeared from the sides to support it. The vehicle was created for research and marketing purposes, with no intention to put it into production.
Alex Tremulis was the designer and the gyroscopic systems were based on Louis Brennan's theories. The Ford Motor Company of Detroit gave credit for the Gyron to Louis Brennan. Alex Tremulis had started his career with the US Air Force and worked in 1948 at the Wright-Patterson Air Force Base on the concept of Military flying saucers. He then became the chief designer for the ill-fated Tucker automobile before joining Ford, and was also involved with the Tuscan gyroscopic motorcycles and the Gyronaught XU1 gyroscopic car.
The original fiberglass concept was destroyed in the 1962 Ford Rotunda fire. Only the studio model remains today, it was sold at an auction in December 2012 for $40,000.


Young God Records

Young God Records is an independent record label formed by Michael Gira in 1990 that specializes in experimental, avant-garde and often non genre-specific releases. The label was named after an EP released by Gira's band Swans called "Young God".
The label's original intent was to facilitate the release of Swans' music, but while the band was disbanded Young God grew to host the Angels of Light as well as a number of other unique bands and artists, including: Akron/Family, Devendra Banhart, Lisa Germano, Ulan Bator, and Mi and L'au. Swans was re-formed in 2010, and began again releasing music under the Young God label. In 2012, Gira told Pitchfork that Young God would not be putting out any new albums by other bands, citing the decline in revenue.


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AQA

AQA, formerly the Assessment and Qualifications Alliance, is an awarding body in England, Wales and Northern Ireland. It compiles specifications and holds examinations in various subjects at GCSE, AS and A Level and offers vocational qualifications. AQA is a registered charity and independent of the government. However, its qualifications and exam syllabi are regulated by the Government of the United Kingdom, which is the regulator for the public examinations system in England and Wales.
AQA is one of five awarding bodies which are recognised by schools across the country. AQA is also recognised by the regulators of the public exams systems for England, Wales and Northern Ireland to offer GCSE, AS and A Levels in the United Kingdom. AQA also offers the AQA Baccalaureate, a qualification also intended for students in Year 12 and 13 and which includes the study of three A-Levels, an extended project and extra-curricular enrichment activities. AQA is the largest examination board for GCSEs and GCE A Levels in England.
The organisation has several regional offices, the largest being in London, Guildford and Manchester.
Due to the growing number of students taking GCSE and A Level exams, AQA has introduced computerized and digital marking in addition to traditional marking of examinations in order to increase efficiency and accuracy of the examination correction.
History.
AQA was originally formed on 7 November 1997 as an alliance of NEAB and AEB/SEG exam boards and City & Guilds vocational awarding body. NEAB and AEB/SEG formally merged on 1 April 2000. City & Guilds chose to remain independent of the new organisation, but transferred its GNVQ provision to AQA.
AQA holds the candidate records and awards for the following historic exam boards:
Examination reform.
The Conservative Party under Prime Minister David Cameron initiated reforms for A Levels to change from a modular structure to a linear one. British examination boards (Edexcel, AQA, OCR and WJEC) regulated and accredited by the Government of the United Kingdom responded to the government's reform announcements by modifying syllabi of several A Level subjects. However, the Labour Party and in particular the Member of Parliament Tristram Hunt announced that it would seek to halt and reverse the reforms and maintain the modular A-Level system. Labour's policy, and the modular AS- and A-Level system, are supported and promoted by the University of Cambridge and by the University of Oxford.
The organisation announced that it will begin offering courses for which all assessment is carried out through examinations at the end of the course. This is commonly referred to as a linear course. Beforehand, they offered modular courses in England with several exams.
Chief executives.
The Chief Executive of AQA runs the organisation on a day-to-day basis, while being accountable to the AQA Council. The role was known as the Director General from its introduction in April 1998 until July 2010.


Sciothericum telescopicum

Sciothericum telescopicum was a sundial (sciothericum) that incorporated a telescope (telescopicum) for greater accuracy in determining exactly when noon occurred. It was invented by William Molyneux in Ireland in 1686. The device used a telescopic site to determine the position of the center of the sun relative to a double gnomon and could thus determine the time of noon to within 15 seconds. The improved accuracy was important for geography, navigation and astronomy calculations.


New York City Independent Film Festival

The New York City Independent Film Festival (a.k.a. NYC Independent Film Festival, NYCIndieFF) is an annual film festival held in New York City. It was founded in 2009 by Dennis Cieri and Bonnie Rush. The festival has screened over 1,800 movies from 81 different countries since it began in 2010.
External links.
Official website https://www.nycindieff.com/


Likelihood ratio


Diffraction in time

Diffraction in time is a phenomenon associated with the quantum dynamics of suddenly released matter waves initially confined in a region of space. It was introduced in 1952 by Marcos Moshinsky with the "shutter problem". A matter-wave beam stopped by an absorbing shutter exhibits an oscillatory density profile during its propagation after removal of the shutter. Whenever this propagation is accurately described by the time-dependent Schrödinger equation, the transient wave functions resemble the solutions that appear for the intensity of light subject to Fresnel diffraction by a straight edge. For this reason, the transient phenomenon was dubbed diffraction in time and has since then been recognised as ubiquitous in quantum dynamics. The experimental confirmation of this phenomenon was only achieved about half a century later in the group of ultracold atoms directed by Jean Dalibard.


Orbit of the Moon

The Moon orbits Earth in the prograde direction and completes one revolution relative to the Vernal Equinox and the stars in about 27.32 days (a tropical month and sidereal month) and one revolution relative to the Sun in about 29.53 days (a synodic month). Earth and the Moon orbit about their barycentre (common center of mass), which lies about from Earth's center (about 72% of its radius). On average, the distance to the Moon is about from Earth's center, which corresponds to about 60 Earth radii or 1.282 light-seconds.
With a mean orbital velocity of 1.022 km/s (0.635 miles/s), the Moon covers a distance approximately its diameter, or about half a degree on the celestial sphere, each hour. The Moon differs from most satellites of other planets in that its orbit is close to the ecliptic plane instead of to its primary's (in this case, Earth's) equatorial plane. The Moon's orbital plane is inclined by about 5.1° with respect to the ecliptic plane, whereas the Moon's equatorial plane is tilted by only 1.5°.
Properties.
The properties of the orbit described in this section are approximations. The Moon's orbit around Earth has many variations (perturbations) due to the gravitational attraction of the Sun and planets, the study of which (lunar theory) has a long history.
Elliptic shape.
The orbit of the Moon is a nearly circular ellipse about the Earth (the semimajor and semiminor axes are 384,400 km and 383,800 km, respectively: a difference of only 0.16%). The equation of the ellipse yields an eccentricity of 0.0549 and perigee  and apogee distances of 362,600 km and 405,400 km respectively (a difference of 12%).
Since nearer objects appear larger, the Moon's apparent size changes as it moves toward and away from an observer on Earth. An event referred to as a 'supermoon' occurs when the full Moon is at its closest to Earth (perigee). The largest possible apparent diameter of the Moon is the same 12% larger (as perigee versus apogee distances) than the smallest; the apparent area is 25% more and so is the amount of light it reflects toward Earth.
The variance in the Moon's orbital distance corresponds with changes in its tangential and angular speeds, as stated in Kepler's second law. The mean angular movement relative to an imaginary observer at the Earth–Moon barycentre is ° per day to the east (J2000.0 epoch).
Elongation.
The Moon's elongation is its angular distance east of the Sun at any time. At new moon, it is zero and the Moon is said to be in conjunction. At full moon, the elongation is 180° and it is said to be in opposition. In both cases, the Moon is in syzygy, that is, the Sun, Moon and Earth are nearly aligned. When elongation is either 90° or 270°, the Moon is said to be in quadrature.
Precession.
The orientation of the orbit is not fixed in space but rotates over time. This orbital precession is also called apsidal precession and is the rotation of the Moon's orbit within the orbital plane, i.e. the axes of the ellipse change direction. The Moon's major axis – the longest diameter of the orbit, joining its nearest and farthest points, the perigee and apogee, respectively – makes one complete revolution every 8.85 Earth years, or 3,232.6054 days, as it rotates slowly in the same direction as the Moon itself (direct motion) - meaning precesses eastward by 360°. The Moon's apsidal precession is distinct from the nodal precession of its orbital plane and axial precession of the moon itself.
Inclination.
The mean inclination of the lunar orbit to the ecliptic plane is 5.145°. Theoretical considerations show that the present inclination relative to the ecliptic plane arose by tidal evolution from an earlier near-Earth orbit with a fairly constant inclination relative to Earth's equator. It would require an inclination of this earlier orbit of about 10° to the equator to produce a present inclination of 5° to the ecliptic. It is thought that originally the inclination to the equator was near zero, but it could have been increased to 10° through the influence of planetesimals passing near the Moon while falling to the Earth. If this had not happened, the Moon would now lie much closer to the ecliptic and eclipses would be much more frequent.
The rotational axis of the Moon is not perpendicular to its orbital plane, so the lunar equator is not in the plane of its orbit, but is inclined to it by a constant value of 6.688° (this is the obliquity). As was discovered by Jacques Cassini in 1722, the rotational axis of the Moon precesses with the same rate as its orbital plane, but is 180° out of phase "(see Cassini's Laws)". Therefore, the angle between the ecliptic and the lunar equator is always 1.543°, even though the rotational axis of the Moon is not fixed with respect to the stars.
Nodes.
The nodes are points at which the Moon's orbit crosses the ecliptic. The Moon crosses the same node every 27.2122 days, an interval called the "draconic month" or "draconitic month". The line of nodes, the intersection between the two respective planes, has a retrograde motion: for an observer on Earth, it rotates westward along the ecliptic with a period of 18.6 years or 19.3549° per year. When viewed from the celestial north, the nodes move clockwise around Earth, opposite to Earth's own spin and its revolution around the Sun. Lunar and solar eclipses can occur when the nodes align with the Sun, roughly every 173.3 days. Lunar orbit inclination also determines eclipses; shadows cross when nodes coincide with full and new moon when the Sun, Earth, and Moon align in three dimensions.
In effect, this means that the "tropical year" on the Moon is only 347 days long. This is called the draconic year or eclipse year. The "seasons" on the Moon fit into this period. For about half of this draconic year, the Sun is north of the lunar equator (but at most 1.543°), and for the other half, it is south of the lunar equator. Obviously, the effect of these seasons is minor compared to the difference between lunar night and lunar day. At the lunar poles, instead of usual lunar days and nights of about 15 Earth days, the Sun will be "up" for 173 days as it will be "down"; polar sunrise and sunset takes 18 days each year. "Up" here means that the centre of the Sun is above the horizon. Lunar polar sunrises and sunsets occur around the time of eclipses (solar or lunar). For example, at the Solar eclipse of March 9, 2016, the Moon was near its descending node, and the Sun was near the point in the sky where the equator of the Moon crosses the ecliptic. When the Sun reaches that point, the centre of the Sun sets at the lunar north pole and rises at the lunar south pole.
Inclination to the equator and lunar standstill.
Every 18.6 years, the angle between the Moon's orbit and Earth's equator reaches a maximum of 28°36′, the sum of Earth's equatorial tilt (23°27′) and the Moon's orbital inclination (5°09′) to the ecliptic. This is called "major lunar standstill". Around this time, the Moon's declination will vary from −28°36′ to +28°36′. Conversely, 9.3 years later, the angle between the Moon's orbit and Earth's equator reaches its minimum of 18°20′. This is called a "minor lunar standstill". The last lunar standstill was a minor standstill in October 2015. At that time the descending node was lined up with the equinox (the point in the sky having right ascension zero and declination zero). The nodes are moving west by about 19° per year. The Sun crosses a given node about 20 days earlier each year.
When the inclination of the Moon's orbit to the Earth's equator is at its minimum of 18°20′, the centre of the Moon's disk will be above the horizon every day from latitudes less than 71°40' (90° − 18°20') north or south. When the inclination is at its maximum of 28°36', the centre of the Moon's disk will be above the horizon every day only from latitudes less than 61°24' (90° − 28°36') north or south.
At higher latitudes, there will be a period of at least one day each month when the Moon does not rise, but there will also be a period of at least one day each month when the Moon does not set. This is similar to the seasonal behaviour of the Sun, but with a period of 27.2 days instead of 365 days. Note that a point on the Moon can actually be visible when it is about 34 arc minutes below the horizon, due to atmospheric refraction.
Because of the inclination of the Moon's orbit with respect to the Earth's equator, the Moon is above the horizon at the North and South Pole for almost two weeks every month, even though the Sun is below the horizon for six months at a time. The period from moonrise to moonrise at the poles is a tropical month, about 27.3 days, quite close to the sidereal period. When the Sun is the furthest below the horizon (winter solstice), the Moon will be full when it is at its highest point. When the Moon is in Gemini it will be above the horizon at the North Pole, and when it is in Sagittarius it will be up at the South Pole.
The Moon's light is used by zooplankton in the Arctic when the Sun is below the horizon for months and must have been helpful to the animals that lived in Arctic and Antarctic regions when the climate was warmer.
History of observations and measurements.
About 1000 BC, the Babylonians were the first human civilization known to have kept a consistent record of lunar observations. Clay tablets from that period, which have been found over the territory of present-day Iraq, are inscribed with cuneiform writing recording the times and dates of moonrises and moonsets, the stars that the Moon passed close by, and the time differences between rising and setting of both the Sun and the Moon around the time of the full moon. Babylonian astronomy discovered the three main periods of the Moon's motion and used data analysis to build lunar calendars that extended well into the future. This use of detailed, systematic observations to make predictions based on experimental data may be classified as the first scientific study in human history. However, the Babylonians seem to have lacked any geometrical or physical interpretation of their data, and they could not predict future lunar eclipses (although "warnings" were issued before likely eclipse times).
Ancient Greek astronomers were the first to introduce and analyze mathematical models of the motion of objects in the sky. Ptolemy described lunar motion by using a well-defined geometric model of epicycles and evection.
Sir Isaac Newton was the first to develop a complete theory of motion, mechanics. The observations of the lunar motion were the main test of his theory.
Lunar periods.
There are several different periods associated with the lunar orbit. The sidereal month is the time it takes to make one complete orbit around Earth with respect to the fixed stars. It is about 27.32 days. The synodic month is the time it takes the Moon to reach the same visual phase. This varies notably throughout the year, but averages around 29.53 days. The synodic period is longer than the sidereal period because the Earth–Moon system moves in its orbit around the Sun during each sidereal month, hence a longer period is required to achieve a similar alignment of Earth, the Sun, and the Moon. The anomalistic month is the time between perigees and is about 27.55 days. The Earth–Moon separation determines the strength of the lunar tide raising force.
The draconic month is the time from ascending node to ascending node. The time between two successive passes of the same ecliptic longitude is called the tropical month. The latter three periods are slightly different from the sidereal month.
The average length of a calendar month (a twelfth of a year) is about 30.4 days. This is not a lunar period, though the calendar month is historically related to the visible lunar phase.
Tidal evolution.
The gravitational attraction that the Moon exerts on Earth is the cause of tides in both the ocean and the solid Earth; the Sun has a smaller tidal influence. The solid Earth responds quickly to any change in the tidal forcing, the distortion taking the form of an ellipsoid with the high points roughly beneath the Moon and on the opposite side of Earth. This is a result of the high speed of seismic waves within the solid Earth.
However the speed of seismic waves is not infinite and, together with the effect of energy loss within the Earth, this causes a slight delay between the passage of the maximum forcing due to the Moon across and the maximum Earth tide. As the Earth rotates faster than the Moon travels around its orbit, this small angle produces a gravitational torque which slows the Earth and accelerates the Moon in its orbit.
In the case of the ocean tides, the speed of tidal waves in the ocean is far slower than the speed of the Moon's tidal forcing. As a result, the ocean is never in near equilibrium with the tidal forcing. Instead, the forcing generates the long ocean waves which propagate around the ocean basins until eventually losing their energy through turbulence, either in the deep ocean or on shallow continental shelves.
Although the ocean's response is the more complex of the two, it is possible to split the ocean tides into a small ellipsoid term which affects the Moon plus a second term which has no effect. The ocean's ellipsoid term also slows the Earth and accelerates the Moon, but because the ocean dissipates so much tidal energy, the present ocean tides have an order of magnitude greater effect than the solid Earth tides.
Because of the tidal torque, caused by the ellipsoids, some of Earth's angular (or rotational) momentum is gradually being transferred to the rotation of the Earth–Moon pair around their mutual centre of mass, called the barycentre. See tidal acceleration for a more detailed description.
This slightly greater orbital angular momentum causes the Earth–Moon distance to increase at approximately 38 millimetres per year. Conservation of angular momentum means that Earth's axial rotation is gradually slowing, and because of this its day lengthens by approximately 23 microseconds every year (excluding glacial rebound). Both figures are valid only for the current configuration of the continents. Tidal rhythmites from 620 million years ago show that, over hundreds of millions of years, the Moon receded at an average rate of per year (2200 km or 0.56% or the Earth-moon distance per hundred million years) and the day lengthened at an average rate of 12 microseconds per year (or 20 minutes per hundred million years), both about half of their current values.
The present high rate may be due to near resonance between natural ocean frequencies and tidal frequencies. Another explanation is that in the past the Earth rotated much faster, a day possibly lasting only 9 hours on the early Earth. The resulting tidal waves in the ocean would have then been much shorter and it would have been more difficult for the long wavelength tidal forcing to excite the short wavelength tides.
The Moon is gradually receding from Earth into a higher orbit, and calculations suggest that this would continue for about 50 billion years. By that time, Earth and the Moon would be in a mutual spin–orbit resonance or tidal locking, in which the Moon will orbit Earth in about 47 days (currently 27 days), and both the Moon and Earth would rotate around their axes in the same time, always facing each other with the same side. This has already happened to the Moon—the same side always faces Earth—and is also slowly happening to the Earth. However, the slowdown of Earth's rotation is not occurring fast enough for the rotation to lengthen to a month before other effects change the situation: approximately 2.3 billion years from now, the increase of the Sun's radiation will have caused Earth's oceans to evaporate, removing the bulk of the tidal friction and acceleration.
Libration.
The Moon is in synchronous rotation, meaning that it keeps the same face toward Earth at all times. This synchronous rotation is only true on average because the Moon's orbit has a definite eccentricity. As a result, the angular velocity of the Moon varies as it orbits Earth and hence is not always equal to the Moon's rotational velocity which is more constant. When the Moon is at its perigee, its orbital motion is faster than its rotation. At that time the Moon is a bit ahead in its orbit with respect to its rotation about its axis, and this creates a perspective effect which allows us to see up to eight degrees of longitude of its eastern (right) far side. Conversely, when the Moon reaches its apogee, its orbital motion is slower than its rotation, revealing eight degrees of longitude of its western (left) far side. This is referred to as "optical libration in longitude".
The Moon's axis of rotation is inclined by in total 6.7° relative to the normal to the plane of the ecliptic. This leads to a similar perspective effect in the north–south direction that is referred to as "optical libration in latitude", which allows one to see almost 7° of latitude beyond the pole on the far side. Finally, because the Moon is only about 60 Earth radii away from Earth's centre of mass, an observer at the equator who observes the Moon throughout the night moves laterally by one Earth diameter. This gives rise to a "diurnal libration", which allows one to view an additional one degree's worth of lunar longitude. For the same reason, observers at both of Earth's geographical poles would be able to see one additional degree's worth of libration in latitude.
Besides these "optical librations" caused by the change in perspective for an observer on Earth, there are also "physical librations" which are actual nutations of the direction of the pole of rotation of the Moon in space: but these are very small.
Path of Earth and Moon around Sun.
When viewed from the north celestial pole (i.e., from the approximate direction of the star Polaris) the Moon orbits Earth anticlockwise and Earth orbits the Sun anticlockwise, and the Moon and Earth rotate on their own axes anticlockwise.
The right-hand rule can be used to indicate the direction of the angular velocity. If the thumb of the right hand points to the north celestial pole, its fingers curl in the direction that the Moon orbits Earth, Earth orbits the Sun, and the Moon and Earth rotate on their own axes.
In representations of the Solar System, it is common to draw the trajectory of Earth from the point of view of the Sun, and the trajectory of the Moon from the point of view of Earth. This could give the impression that the Moon orbits Earth in such a way that sometimes it goes backwards when viewed from the Sun's perspective. However, because the orbital velocity of the Moon around Earth (1 km/s) is small compared to the orbital velocity of Earth about the Sun (30 km/s), this never happens. There are no rearward loops in the Moon's solar orbit.
Considering the Earth–Moon system as a binary planet, its centre of gravity is within Earth, about or 72.6% of the Earth's radius from the centre of the Earth. This centre of gravity remains on the line between the centres of the Earth and Moon as the Earth completes its diurnal rotation. The path of the Earth–Moon system in its solar orbit is defined as the movement of this mutual centre of gravity around the Sun. Consequently, Earth's centre veers inside and outside the solar orbital path during each synodic month as the Moon moves in its orbit around the common centre of gravity.
The Sun's gravitational effect on the Moon is more than twice that of Earth's on the Moon; consequently, the Moon's trajectory is always convex (as seen when looking Sunward at the entire Sun–Earth–Moon system from a great distance outside Earth–Moon solar orbit), and is nowhere concave (from the same perspective) or looped. That is, the region enclosed by the Moon's orbit of the Sun is a convex set.


3345 Tarkovskij

3345 Tarkovskij, provisional designation "", is a carbonaceous background asteroid from the inner regions of the asteroid belt, approximately in diameter. It was discovered on 23 December 1982, by Russian astronomer Lyudmila Karachkina at the Crimean Astrophysical Observatory in Nauchnyj, on the Crimean peninsula, and named after film-director Andrei Tarkovsky. The C-type asteroid is a slow rotator with a rotation period of 187 hours.
Orbit and classification.
"Tarkovskij" is a non-family asteroid from the main belt's background population. It orbits the Sun in the inner main-belt at a distance of 2.0–2.9 AU once every 3 years and 11 months (1,420 days). Its orbit has an eccentricity of 0.19 and an inclination of 16° with respect to the ecliptic.
It was first observed as "" at the Heidelberg Observatory in 1938, extending the body's observation arc by 44 years prior to its official discovery observation at Nauchnyj.
Naming.
This minor planet named after the Soviet theater director and film-maker Andrei Tarkovsky (1932—1986). The approved naming citation was published by the Minor Planet Center on 31 May 1988 ().
Physical characteristics.
In the SMASS classification, "Tarkovskij" is a carbonaceous C-type asteroid, unusual for inner-belt asteroids which are typically of a stony composition.
Slow rotator.
In January 2014, a rotational lightcurve of "Tarkovskij" was obtained from photometric observations taken at the Belgrade Observatory and the CS3 DanHenge Observatory . Lightcurve analysis gave a rotation period of 187 hours with a brightness variation of 0.59 magnitude (). This makes it a slow rotator, as most asteroids have periods shorter than 20 hours.
Diameter and albedo.
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, "Tarkovskij" measures between 21.02 and 24.17 kilometers in diameter and its surface has an albedo between 0.0407 and 0.096. The "Collaborative Asteroid Lightcurve Link" derives an albedo of 0.0526 and adopts a diameter of 24.17 kilometers with on an absolute magnitude of 11.9 from the IRAS results.


3376 Armandhammer


3430 Bradfield

3430 Bradfield ("prov. designation": ) is a stony Agnia asteroid from the central regions of the asteroid belt, approximately in diameter. It was discovered on 9 October 1980, by American astronomer Carolyn Shoemaker at the Palomar Observatory in California. The Sq-type asteroid was named after comet hunter William A. Bradfield.
Orbit and classification.
When applying the hierarchical clustering method to its proper orbital elements according to Nesvorný, "Bradfield" is a member of the Agnia family (), a very large family of stony asteroids with more than 2000 known members. They most likely formed from the breakup of a basalt object, which in turn was spawned from a larger parent body that underwent igneous differentiation. The family's parent body and namesake is the asteroid 847 Agnia. In the 1995-HCM analysis by Zappalà, however, it is a member of the Liberatrix family (also described as Nemesis family by Nesvorný).
It orbits the Sun in the central main-belt at a distance of 2.5–3.0 AU once every 4 years and 7 months (1,674 days; semi-major axis of 2.76 AU). Its orbit has an eccentricity of 0.10 and an inclination of 4° with respect to the ecliptic. The body's observation arc begins with its observations as at Cerro El Roble Observatory in April 1974, more than 6 years prior to its official discovery observation at Palomar.
Naming.
This minor planet was named after New Zealand-born Australian amateur astronomer and rocket engineer William A. Bradfield (1927–2014). A discoverer of several comets himself, he significantly increased the rate of discovery of bright comets from the southern hemisphere during the 1970s and 1980s. The official naming citation was published by the Minor Planet Center on 14 April 1987 ().
Physical characteristics.
In the SMASS classification, "Bradfield" is an Sq-subtype, that transitions between the common, stony S-type and Q-type asteroids.
Diameter and albedo.
According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, "Bradfield" measures 8.492 kilometers in diameter and its surface has an albedo of 0.269.
Rotation period.
As of 2018, no rotational lightcurve of "Bradfield" has been obtained from photometric observations. The body's rotation period, pole and shape remain unknown.


Cosmic View

Cosmic View: The Universe in 40 Jumps is a 1957 book by Dutch educator Kees Boeke that combines writing and graphics to explore many levels of size and structure, from the astronomically vast to the atomically tiny. The book begins with a photograph of a Dutch girl sitting outside a school and holding a cat. The text backs up from the original photo, with graphics that include more and more of the vast reaches of space in which the girl is located. It then narrows in on the original picture, with graphics that show ever smaller areas until the nucleus of a sodium atom is reached. Boeke writes commentary on each graphic, along with introductory and concluding notes.
Summary and themes.
In his introduction Boeke says the work originated with a school project at his Werkplaats Children's Community in Bilthoven. The idea was to draw pictures that would include ever-growing areas of space, to show how the Earth is located in an unfathomably enormous universe. Boeke then writes that he realized the reverse process—creating graphics of tinier and tinier bits of reality—would reveal a world "as full of marvels" as the most gigantic reaches of outer space.
The result is a voyage outward and inward from the familiar human scale. The ordinary photograph of a schoolgirl and a cat proves to be the starting point for an insightful visit to levels of reality that can only be imagined, and about which little may be known. In his conclusion Boeke speculates that the imaginary voyage depicted may help "just a little" to make mankind realize the enormousness of the cosmic powers that the human race has begun to master.
Boeke injected some humor into the book. He puts a blue whale into his graphics, incongruously lying alongside the girl and her cat, to give an idea of relative sizes. In his voyage into the smaller realms of reality, he includes an "Anopheles" mosquito that looks like a creature from a fifties science fiction film movie.
Influence.
Boeke's book attracted much attention and was included in Mortimer Adler's "Gateway to the Great Books" (1963) series. Many of the graphics are impressive realizations of the differences in size that lie hidden from our normal view. The graphics that show ever greater areas of the Earth, for instance, are interesting precursors to the satellite photos now available on the Internet.
Boeke's essay/book is recognized in the credits of three short documentary films:
It is also the basis of the interactive iOS app "Cosmic Eye" (2012), whose developer has also made a three-minute video from it, also called "Cosmic Eye" (2012, re-released 2018).


Sedimental

Sedimental is an independent recording label based in Greenfield, Massachusetts releasing mainly experimental, sound art, noise, free jazz, avant garde and drone music. It began 20 years ago in Austin, Texas with the first album from ambient-drone group Stars of the Lid and their debut "Music for Nitrous Oxide" in 1995. It has followed up to present day with specialized releases from Phill Niblock, Kyle Bobby Dunn, Francisco Lopez, Brendan Murray, and Alessandro Bosetti. Most of which are limited editions of 500 copies.
The label prints and presses their vinyl and compact disc releases in house and often with a unique, non-plastic gatefold sleeve.
Related activities include radio (wzbc 90.3 fm- Boston) and Non-Event in conjunction with Dan Hirsch, Susanna Bolle and Bhob Rainey in promoting local, national and international experimental and improvising artists in live settings for the Boston area as well as Mental-Drift in coordinating very infrequent performances in the Pioneer Valley.


London International Festival of Exploratory Music

The London International Festival of Exploratory Music (LIFEM) is an annual music festival established in 2009 staged at the beginning of November in London, England, United Kingdom. It brings together musicians from across the world, in what the festival defines as exploratory music. Acts that have appeared at the festival include: Terry Riley, Talvin Singh, George Brooks, Wim Mertens, Bruno Sanfilippo, Sylvain Chauveau, Pascal Comelade, Gavin Bryars, Hortus Musicus, Tanya Tagaq, Andrew Poppy, Lonely China Day, Les Yeux Noirs, Cukunft, DJ Scotch Egg, , , Nive Nielsen, Jenni Roditi, Lorcan Mac Mathuna, Coletivo Radio Cipo, Da Cruz, Monster Ceilidh Band, Midori Hirano and .
The 2012 festival was staged in Kings Place.


Lease (computer science)

In computer science, a Lease is a contract that gives its holder specified rights to some resource for a limited period. Because it is time-limited, a lease is an alternative to a lock for resource serialization.
Motivation.
A traditional resource lock is granted until it is explicitly released by the locking client process. Reasons why a lock might not be released include:
Any of these could end the availability of an important reusable resource until the system is reset. By contract, a lease is valid for a limited period, after which it automatically expires, making the resource available for reallocation by a new client.
History.
The term 'lease' was applied to this concept in a 1989 paper by Cary G. Gray and David R. Cheriton, but similar concepts (expiring tokens and breakable locks with timeouts) had been used in prior systems.
Problems.
Leases are commonly used in distributed systems for applications ranging from DHCP address allocation to file locking, but they are not (by themselves) a complete solution:


487 Venetia

Venetia (minor planet designation: 487 Venetia), provisional designation , is a rare-type stony asteroid from the middle regions of the asteroid belt, approximately 63 kilometers in diameter. It was discovered on 9 July 1902, by Italian astronomer Luigi Carnera at Heidelberg Observatory in southwest Germany. It was later named for the Italian Veneto region where the city of Venice is located.
Orbit and classification.
"Venetia" orbits the Sun in the middle main-belt at a distance of 2.4–2.9 AU once every 4 years and 4 months (1,593 days). Its orbit has an eccentricity of 0.09 and an inclination of 10° with respect to the ecliptic.
The body's observation arc begins in 1913, at the Collegio Romano Observatory () in Italy, approximately 17 months after its official discovery observation at Heidelberg.
Physical characteristics.
On the taxonomic scheme, "Venetia" is a common, featureless S-type asteroid. More recently, polarimetric observations refined its classification to a rare K-type asteroid.
Rotation period.
In March 2014, the so-far best rated rotational lightcurve was obtained by Italian astronomer Andrea Ferrero at the Bigmuskie Observatory () in Mombercelli, Italy. It gave a well-defined rotation period of 13.34 hours with a brightness variation of 0.20 magnitude (). The result supersedes previously measured periods of 10.62 to 18 hours.
Spin axis.
In two separate studies, groups of German, Russian and Swedish astronomers also modeled "Venetia"s lightcurve from various data sources in 2000 and 2002. They found two spin axes of (259.0°, −30.0°) and (268.0°, −24.0°) in ecliptic coordinates (λ, β), as well as a concurring rotation period of 13.33170 and 13.34153 hours, respectively ().
Diameter and albedo.
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, "Venetia" measures between 59.046 and 66.13 kilometers in diameter and its surface has an albedo between 0.228 and 0.328. The "Collaborative Asteroid Lightcurve Link" adopts the results obtained by IRAS, that is, an albedo of 0.2457 and a diameter of 63.15 kilometers with an absolute magnitude of 8.14.
Naming.
This minor planet was named for the region of Veneto with its capital and largest city Venice. The region is located in northeast Italy between the Po River and the Alps. Naming was proposed by Italian astronomer Elia Millosevich.
Naming citation was first mentioned in "The Names of the Minor Planets" by Paul Herget in 1955 () and amended by Lutz Schmadel for the "Dictionary of Minor Planet Names" based on a private communication with astronomer Piero Sicoli.


Kinetic family drawing

Figure drawings are projective diagnostic techniques in which an individual is instructed to draw a person, an object or a situation, so that cognitive, interpersonal, or psychological functioning can be assessed. The Kinetic Family Drawing, developed in 1970 by Burns and Kaufman, requires the test-taker to draw a picture of his or her entire family. Children are asked to draw a picture of their family, including themselves, "doing something." This picture is meant to elicit the child's attitudes toward his or her family and the overall family dynamics. The KFD is sometimes interpreted as part of an evaluation of child abuse.
Interpretations of all projective tests should be made only by a clinical psychologist, or a competent and credentialed art therapist under the supervision of a clinical psychologist, and the limitations of projective tests should be considered. It is generally a good idea to use projective tests as part of an overall test battery.
Method.
Despite the flexibility in administration and interpretation of figure drawings, these tests require skilled and trained administrators familiar with both the theory behind the tests and the structure of the tests themselves. The KFD involves the examiner instructing the child to draw a picture of themselves, and everyone in his or her family, doing something. The examiner may then ask the child questions about the drawing, such as what is happening and who is in the picture. Certain characteristics of the drawing are noted upon analysis, such as the placement of family members; the absence of any members; whether the figures are relatively consistent with reality or altered by the child; the absence of particular body parts; erasures; elevated figures; and so on.
The KFD was created as an extension of the Family Drawing Test (Burns & Kaufman, 1972). The kinetic aspect refers to the instructions given to the child to draw his or her family members "doing" something.
The KFD is similar to other psychometric projective techniques such as the Draw-A-Person Test developed by Machover and the House-Tree-Person (HTP) technique developed by Buck.


2444 Lederle


758 Mancunia

758 Mancunia is a minor planet orbiting the Sun. It was discovered by H. E. Wood (a Mancunian) in Johannesburg in 1912.


Grindometer

A grindometer is a device used to measure the particle size of suspensions, typically inks such as those used in printing, or paints. It consists of a steel block with a channel of varying depth machined into it, starting at a convenient depth for the type of suspension to be measured, and becoming shallower until it ends flush with the block's surface. The depth of the groove is marked off on a graduated scale next to it. The suspension to be tested is poured into the deep end of the groove, and scraped towards the shallow end with a flat metal scraper. At the point where the depth of the groove equals the largest particles in the suspension, irregularities (for example pinholes in an ink sample) will become visible.
The advantages of this method are that it uses a small sample and gives a very quick indication of the high end of the particle size distribution, allowing production processes to be followed in real time.
The following standards are relevant on conjunction with the use of grindometers: ASTM D 1210, ASTM D 1316, JIS K 5600-2-5, ISO 1524, EN ISO 1524, BS 3900-C6


3753 Cruithne

3753 Cruithne is a Q-type, Aten asteroid in orbit around the Sun in 1:1 orbital resonance with Earth, making it a co-orbital object. It is an asteroid that, relative to Earth, orbits the Sun in a bean-shaped orbit that effectively describes a horseshoe, and that can change into a quasi-satellite orbit. Cruithne does not orbit Earth and at times it is on the other side of the Sun, placing Cruithne well outside of Earth's Hill sphere. Its orbit takes it inside the orbit of Mercury and outside the orbit of Mars. Cruithne orbits the Sun in about 1 year but it takes 770 years for the series to complete a horseshoe-shaped movement around the Earth.
The name "Cruithne" is from Irish and refers to the early Picts (Old Irish: "Cruthin") in the "Annals of Ulster" and their eponymous king ("Cruidne, son of Cinge") in the "Pictish Chronicle".
Discovery.
Cruithne was discovered on 10 October 1986 by Duncan Waldron on a photographic plate taken with the UK Schmidt Telescope at Siding Spring Observatory, Coonabarabran, Australia. The 1983 apparition (1983 UH) is credited to Giovanni de Sanctis and Richard M. West of the European Southern Observatory in Chile.
It was not until 1997 that its unusual orbit was determined by Paul Wiegert and Kimmo Innanen, working at York University in Toronto, and Seppo Mikkola, working at the University of Turku in Finland.
Dimensions and orbit.
 Cruithne is approximately in diameter, and its closest approach to Earth is , approximately thirty times the separation between Earth and the Moon. From 1994 through 2015, Cruithne made its annual closest approach to Earth every November.
Although Cruithne's orbit is not thought to be stable over the long term, calculations by Wiegert and Innanen showed that it has probably been synchronized with Earth's orbit for a long time. There is no danger of a collision with Earth for millions of years, if ever. Its orbital path and Earth's do not cross, and its orbital plane is currently tilted to that of the Earth by 19.8°. Cruithne, having a maximum near-Earth magnitude of +15.8, is fainter than Pluto and would require at least a reflecting telescope to be seen.
Cruithne is in a normal elliptic orbit around the Sun. Its period of revolution around the Sun, approximately 364 days at present, is almost equal to that of the Earth. Because of this, Cruithne and Earth appear to "follow" each other in their paths around the Sun. This is why Cruithne is sometimes called "Earth's second moon". However, it does not orbit the Earth and is not a moon. In 2058, Cruithne will come within 0.09 AU () of Mars.
Due to a high orbital eccentricity, Cruithne's distance from the Sun and orbital speed vary a lot more than the Earth's, so from the Earth's point of view Cruithne actually follows a kidney-bean-shaped horseshoe orbit ahead of the Earth, taking slightly less than one year to complete a circuit of the "bean". Because it takes slightly "less" than a year, the Earth "falls behind" the bean a little more each year, and so from our point of view, the circuit is not quite closed, but rather like a spiral loop that moves slowly away from the Earth.
After many years, the Earth will have fallen so far behind that Cruithne will then actually be "catching up" on the Earth from "behind". When it eventually does catch up, Cruithne will make a series of annual close approaches to the Earth and gravitationally exchange orbital energy with Earth; this will alter Cruithne's orbit by a little over half a million kilometres—while Earth's orbit is altered by about —so that its period of revolution around the Sun will then become slightly "more" than a year. The kidney bean will then start to migrate away from the Earth again in the opposite direction instead of the Earth "falling behind" the bean, the Earth is "pulling away from" the bean. The next such series of close approaches will be centred on the year 2292 in July of that year, Cruithne will approach Earth to about .
After 380 to 390 years or so, the kidney-bean-shaped orbit approaches Earth again from the other side, and the Earth, once more, alters the orbit of Cruithne so that its period of revolution around the Sun is again slightly "less" than a year (this last happened with a series of close approaches centred on 1902, and will next happen with a series centered on 2676). The pattern then repeats itself.
Similar minor planets.
More near-resonant near-Earth objects (NEOs) have since been discovered. These include 54509 YORP, , , and which exist in resonant orbits similar to Cruithne's. is the first and so far only identified Earth trojan.
Other examples of natural bodies known to be in horseshoe orbits (with respect to each other) include Janus and Epimetheus, natural satellites of Saturn. The orbits these two moons follow around Saturn are much simpler than the one Cruithne follows, but operate along the same general principles.
Mars has four known co-orbital asteroids (5261 Eureka, , , and , all at the Lagrangian points), and Jupiter has many (an estimated one million greater than 1 km in diameter, the Jovian trojans); there are also other small co-orbital moons in the Saturnian system: Telesto and Calypso with Tethys, and Helene and Polydeuces with Dione. However, none of these follow horseshoe orbits.
In popular culture.
Cruithne plays a major role in Stephen Baxter's novel "", which was nominated for the Arthur C. Clarke Award for best science fiction in 2000.
Cruithne is mentioned on the "QI" season 1 episode "Astronomy", in which it is incorrectly described as a second moon of Earth. In a later episode, this mistake was rectified and it was added that Earth has over 18,000 mini-moons.
In "Astonishing X-Men", Cruithne is the site of a secret lab assaulted by Abigail Brand and her S.W.O.R.D. team. It contains many Brood before Brand destroys it.
In the Insignia trilogy, 3753 Cruithne has been moved into an orbit around Earth to serve as a training ground for the Intrasolar Forces. In the third novel, "Catalyst", it is intentionally directed at the Earth. While it is destroyed before impact, its fragments rain down on the Earth's surface, killing nearly 800 million people across the world.
In the science-fiction book series "Aeon 14", Cruithne appears as an inhabited moonlet, home to 'privateers', smugglers, Terran Space Fleet (TSF) outposts and corporate headquarters. Notable inhabitants have included Ngoba Starl and Petral Dulan.


Richard McLean Badger

Richard McLean Badger (4 May 1896 – 26 November 1974) was an American professor at Caltech and a chemist who specialized in molecular spectroscopy with X rays and infrared radiation. He made pioneering studies on the modes of vibrations and spectral energies in small molecules. The so called Badger's rule relating force and internuclear distance in diatomic molecules is based on his work from 1933.
Badger was born in Elgin, Illinois to Joseph Stillman who worked at General Electric, and Carrie Mabel Hewitt. His father was posted to Brisbane, Australia where he spent his early life. He was then sent to school at Elgin grammar school and again briefly in Australia. He joined Northwestern University in 1916 but was posted into the US Army 311st Field Station Battalion in World War I and was demobilized in 1919. He then went to California to continue his education at the Throop Institute of Technology which became the California Institute of Technology (Caltech) in the next year. He studied crystals using X ray diffraction and was influenced by Richard C. Tolman, Roscoe G. Dickinson, Paul S. Epstein, and Arthur A. Noyes. He received a PhD in 1924 and continued to work as a research fellow. Badger and Tolman worked on examining predictions based on Niels Bohr's ideas. In 1928-29 he visited universities in Germany and studied fluorescence with James Franck in Göttingen. He also worked with Reinhard Mecke in Bonn. He became an assistant professor in 1929 and began to examine hydrogen bonds in organic molecules. During World War II he was also involved in problems coming from the Manhattan Project. He worked alongside Linus Pauling working on Navy sponsored research but he did not share Pauling's pacificm and anti-nuclear testing stance.
Badger married Virginia Alice Sherman in 1933 and they had a son and a daughter.


List of longest mountain chains on Earth

The world's longest above-water mountain range is the Andes, about long. The range stretches from north to south through seven countries in South America, along the west coast of the continent: Venezuela, Colombia, Ecuador, Peru, Bolivia, Chile, and Argentina. Aconcagua is the highest peak, at about .
This list does not include submarine mountain ranges. If submarine mountains are included, the longest is the global mid-ocean ridge system which extends for about 65,000 km(40,389 mi).
Formation.
Mountain chains are typically formed by the process of plate tectonics. Tectonic plates slide very slowly over the Earth's mantle, a lower place of rock that is heated from the Earth's interior. Several huge sections of the earth's crust are impelled by heat currents in the mantle, producing tremendous forces that can buckle the material at the edges of the plates to form mountains. Usually one plate is forced underneath the other, and the lower plate is slowly absorbed by the mantle. Where the two plates pass one another, heated rock from the mantle can burst through the crust to form volcanoes. The movement of the plates against one another can also cause earthquakes.


Bazantar

The bazantar is a custom made string instrument invented by musician Mark Deutsch, who worked on the design between 1993 and 1997 (Patent issued March 16, 1999).
Overview.
The Bazantar is a five-string acoustic bass, fitted with an additional twenty-nine sympathetic strings and four drone strings. The instrument possesses a melodic range of over five octaves, and its sympathetic range spans four octaves. The inventor intends this to create an interplay between melodic, sympathetic, and drone strings to produce a more resonant sound than a conventional upright bass.
History and development.
In the late 1980s, Mark Deutsch began exploring North Indian classical music. The subtlety of this style, combined with his pursuits on the sitar, inspired him to delve deeper into the study of music. He started exploring the mathematics of sound, particularly music's underlying frequency structure. This search revealed nonlinear mathematical patterns that exist in sound and are found universally in the natural world, including the overtone series, fractals, the golden mean, seashells, and the Fibonacci series.
In 1993, Mark began work on the first prototype of the Bazantar, an acoustic bass with additional sympathetic and drone strings. His intent was to create an instrument that would take advantage of these nonlinear mathematical patterns and make them more consciously audible. The difficulty lay in engineering a design that would be able to withstand the tension of the additional strings. He devised the unique solution of constructing a separate housing that would contain both the sympathetic strings and their resultant tension, which would then be mounted onto the instrument. After much experimentation, a finalized version was completed in October 1997.
Final design.
In the finalized version, the drone strings are positioned outside the Bazantar's lowest melody string on a bass bridge, which has been modified to support this configuration. The sympathetic strings are held in a modular graphite housing that is positioned between the feet of the main bridge and mounted at the bottom of the tailpiece and at the base of the neck, underneath the fingerboard. The torque these strings create is contained within this housing. Because none of this torque is transferred to the instrument's body, the stress to its structure is greatly decreased, allowing for increased flexibility throughout the entire design. The Bazantar's engineering strategy enables it to maintain more strings at higher tensions than conventional approaches dictate. This distinguishes its tonal character and contributes to its powerful and complex sound.


Donna Brogan

Donna Jean Brogan (born July 12, 1939) is an American statistician and professor emeritus of statistics at Emory University. Brogan has worked in biostatistical research in the areas of women's health, mental health and psychosocial health statistics, statistics on breast cancer, and analysis of complex survey data.
Early life and education.
Brogan was born July 12, 1939 and grew up in a working-class neighborhood in Baltimore, Maryland, and she was the first in her family to go to college. She earned a B.A. in mathematics from Gettysburg College in 1960, an M.S. in statistics from Purdue University in 1962. She earned a PhD in statistics from Iowa State University in 1967, under the supervision of Joseph Sendransk.
Work.
In 1971, Brogan founded the Caucus for Women in Statistics, and helped to establish the standing ASA Committee on Women in Statistics.
For four years, she was an assistant professor in the University of North Carolina in the School of Public Health, with a specialization in sample survey design and analysis. Then in 1970, she joined the Emory University School of Medicine as associate professor, later professor in the Department of Statistics and Biometry. Between 1991–1994, she was the Division Director of Biostatistics at Emory. She retired in 2004 from Emory University.
Since 1975, she has worked in freelance and active as a biostatistician, primarily in the specialty area of design and analysis of complex sample surveys.
Personal life.
As a woman in mathematics in the 1950s and 1960s, she suffered from many incidents of sex discrimination, including issues with unequal compensation from the University of North Carolina Chapel Hill and Emory University, as well as a legal battle with the DeKalb County voter registrar, which involved the American Civil Liberties Union.
She was married to , and had two children, although their son died in infancy. Brogan and Ruhl later divorced, and Brogan lived as a single mother for several years.
Awards and honors.
She is a Fellow of the American Statistical Association, received the Emory University Thomas Jefferson Award from Emory University in 1993, and was awarded the Iowa State University Distinguished Alumni Award in 2002. In 1995, Iowa State University engraved her name on its "Plaza of Heroines", which honors outstanding women graduates and faculty.
The "Donna J. Brogan Lecture in Biostatistics" was established in 2004 at Emory University, to honor Brogan's work at the school.


Rounds per minute


Cham am


FUVEST

FUVEST (from Portuguese "Fundação Universitária para o Vestibular", "University Foundation for Vestibular") is a Brazilian autonomous institution connected to the University of São Paulo responsible for its "vestibular" examinations. For that reason, USP's vestibular itself is usually called "Fuvest".
FUVEST's exam is considered by most as the most competitive vestibular and demanding exam, only rivalled by the vestibular for the Technological Institute of Aeronautics. Every year, an average of 160,000 candidates take their exams, which usually last several days.
Tests.
FUVEST's exam is split into two parts. The first part consists of a 90 multiple–choice questions test, taken by all applicants (nicknamed as "vestibulandos" in Portuguese) in late November, or early December. They have 5 hours to answer the questions about the following subjects: Portuguese language and Brazilian/Portuguese Literature, Math, Physics, Chemistry, Biology, Geography, History, and English language. Also, according to the candidate's guide, up to 10% of these questions will bear interdisciplinary questions.
Following the first part, FUVEST publishes the "Nota de Corte" (from Portuguese, meaning "Cutoff Mark" or "Cutoff Score"). The Cutoff Score is the result of a simple expression and its value is different for each major. Every candidate who has obtained a score equal to or higher than the Cutoff Mark automatically qualifies to advance to the second part. Candidates who score less than 22 points or score zero in any subject are automatically disqualified.
The second part is usually held in early January and consists of up to four exams. The Portuguese exam is required of all candidates, and so is an exam about all subjects. The remaining required exams (on the third day of this second part) differ depending on the candidate's intended major, usually focusing on more difficult or specific topics. For example, prospective Engineering majors are tested in Math, Physics and Chemistry, while Law School applicants have to take History, Geography and Math exams, and Medical School candidates are examined in Physics, Chemistry and Biology. The Portuguese language exam includes, in addition to essay questions, a student-written essay. In the current format, candidates take only one exam per day over a period of three or four days. Some majors also require specific exams: applicants for Architecture, Design and Arts must attend for such tests.
Moreover, candidates who only attended a public high-school receive an extra 12% on their final scores on the first and second parts, arguably in order to compensate for the general low quality of Brazilian public basic education.
2010 changes.
For the 2010 FUVEST, some significant changes are expected. The first part, scheduled for November 22, will be the same as before, but the points obtained by the candidate will no longer be taken into consideration for his final score. In other words, the first part will serve as an elimination test.
For the second part, greater changes have been made. The examination will last for three consecutive days (from January 3 to 5). In the first day, candidates will do the Portuguese language test and the essay exam. On the second day, there will be 18 write-in questions covering all subjects of high school, 6 being interdisciplinary. In the third day, specific questions will be presented in the exam to the candidate, depending on his career of choice. For example, students applying for any course in the Humanities will be asked and questioned about subjects regarding the humanities such as history, or geography, while candidates for the Exact Sciences will be questioned about subjects such as mathematics and chemistry, and so on and so forth.
Careers that require special tests (such as Music or Architecture) will have their own specific tests regarding the desired subjects of the candidates at a time around the end of the year.
Required books.
Candidates are requested to read a total of nine books, due to the fact that the exams will present questions regarding the stated books. Not all of them will be covered by the test, usually only three are mentioned throughout the test, but the student is unable to know which of them he will be asked about. For the 2013-2014-2015 vestibulars, the required books are:


Attrition (epidemiology)

In science, attrition are ratios regarding the loss of participants during an experiment. Attrition rates are values that indicate the participant drop out. Higher attrition rates are found in longitudinal studies.


Essence Music

Essence Music is an independent record label based in Juiz de Fora, Brazil. All the albums are released in a standard edition and a special edition, which is a hand-made box including the standard edition of the album, various inserts, and usually a bonus disc.


Placement exam

A placement exam or placement test is a test designed to evaluate a person's preexisting knowledge of a subject and thus determine the level most suitable for the person to begin coursework on that subject.
In many countries, including the United States, it is not unusual for students to take a placement exam in a subject such as mathematics upon entering middle or high school to determine what level of classes they should take. Typically, students are then placed on a tracking system determined by the class they are approved to enter—for example, if a student takes music theory to students whose knowledge in that area is more advanced than what a typical entering freshman's would be in those subjects. Scores on such exams as the Advanced Placement, International Baccalaureate, SAT Subject Tests, and British Advanced Level exams can also serve as placement tests for students in certain subjects, where a high score would enable them to get into a more advanced class than what a freshman would normally take.