Roy Campanella, nicknamed "Campy", was an American baseball player as a catcher. The Philadelphia native played in the Negro Leagues and Mexican League for several seasons before entering the minor leagues in 1946, he made his Major League Baseball debut in 1948. His playing career ended when he was paralyzed in an automobile accident in January 1958. Considered to be one of the greatest catchers in the history of the game, Campanella played with the Brooklyn Dodgers in the 1940s and 1950s. After he retired as a player as a result of the accident, Campanella held positions in scouting and community relations with the Dodgers, he was inducted into the Baseball Hall of Fame in 1969. He was born Roy Campanella in Philadelphia to parents Ida, African American, John Campanella, son of Italian immigrants. Roy was one of four children born to the couple, they first lived in Germantown, moved to Nicetown in North Philadelphia, where the children attended integrated schools. Because of their mixed race, he and his siblings were sometimes harassed by other children in school.

But Campanella had athletic gifts. He was elected captain of every sport team he played on in high school, but baseball was his passion. Of mixed-race, Campanella was considered on the wrong side of the baseball color line and prohibited from MLB play, he dropped out of high school on his sixteenth birthday and began playing Negro league baseball in 1937 for the Washington Elite Giants. The Elite Giants moved to Baltimore the following year, Campanella became a star player with the team. In 1942 and 1943, Campanella played in the Mexican League with the Monterrey Sultans. Lázaro Salazar, the team's manager, told Campanella that one day he would play at the major league level. Campanella moved into the Brooklyn Dodgers' minor league system in 1946 as the Dodger organization began preparations to break the MLB color barrier with Jackie Robinson, his easy-going personality and strong work ethic were credited with his being able to move between the races. Although Branch Rickey considered hiring Campanella to break baseball's color barrier, Rickey decided upon Robinson.

For the 1946 season, Robinson was assigned to the Montreal Royals, the Dodgers' affiliate in the Class AAA International League. On March 18, 1946, Campanella signed a contract to play for Danville Dodgers of the Illinois–Indiana–Iowa League. After the general manager of the Danville Dodgers reported that he did not feel the league was ready for racial integration, the organization sent Campanella and pitcher Don Newcombe to the Nashua Dodgers of the Class B New England League, where the Dodgers felt the climate would be more tolerant; the Nashua team thus became the first professional baseball team of the 20th century to field a racially integrated lineup in the United States. Campanella's 1946 season proceeded without racist incidents, in one game Campanella assumed the managerial duties after manager Walter Alston was ejected. Campanella was the first African American to manage Caucasian players of an organized professional baseball team. Nashua was three runs down at the time Campanella took over.

They came back to win, in part due to Campanella's decision to use Newcombe as a pinch hitter during the seventh inning. Jackie Robinson's first season in the major leagues came in 1947, Campanella began his MLB career with the Brooklyn Dodgers the following season, playing his first game on April 20, 1948. In years and his wife sometimes stayed with the Campanella family during some ballgames because adequate hotels for blacks could not be found in the city. Campanella played for the Dodgers from 1948 through 1957 as their regular catcher. In 1948, he had three different uniform numbers before settling on 39 for the rest of his career. Campanella was selected to the All-Star Game every year from 1949 through 1956. With his 1949 All-Star selection, he was one of the first four African Americans so honored. In 1950 Campanella hit home runs in five straight games. Campanella received the Most Valuable Player award in the National League three times: in 1951, 1953, 1955. In each of his MVP seasons, he batted more than.300, hit more than 30 home runs, had more than 100 runs batted in.

His 142 RBI during 1953 exceeded the franchise record of 130, held by Jack Fournier and Babe Herman. Today it is the second most in franchise history, Tommy Davis breaking it with 153 RBI in 1962; that same year, Campanella hit 40 home runs in games in which he appeared as a catcher, a record that lasted until 1996, when it was exceeded by Todd Hundley. During his career, he threw out 57% of the base runners who tried to steal a base on him, the highest by any catcher in major league history. Campanella had five of the seven top caught stealing percentages for a single season in major league history. In 1955, he helped. After the Dodgers lost the first two games of the series to the Yankees, Campanella began Brooklyn's comeback by hitting a two-out, two-run home run in the first inning of Game 3; the Dodgers won that game, got another home run from Campanella in a Game 4 victory that tied the series, went on to claim the series in seven games when Johnny Podres shutout the Yankees 2-0 in Game 7.

Campanella caught three no-hitters during his career: Carl Erskine's two on June 19, 1952 and May 12, 1956

This is a list of the National Register of Historic Places listings in Charlottesville, Virginia. This is intended to be a complete list of the properties and districts on the National Register of Historic Places in the independent city of Charlottesville, United States; the locations of National Register properties and districts for which the latitude and longitude coordinates are included below, may be seen in an online map. There are 65 districts listed on the National Register in the city; this National Park Service list is complete through NPS recent listings posted February 28, 2020. List of National Historic Landmarks in Virginia National Register of Historic Places listings in Virginia National Register of Historic Places listings in Albemarle County, Virginia

Stochastic resonance is a phenomenon that occurs in a threshold measurement system when an appropriate measure of information transfer is maximized in the presence of a non-zero level of stochastic input noise thereby lowering the response threshold. The three criteria that must be met for stochastic resonance to occur are: Nonlinear device or system: the input-output relationship must be nonlinear Weak, periodic signal of interest: the input signal must be below threshold of measurement device and recur periodically Added input noise: there must be random, uncorrelated variation added to signal of interestStochastic resonance occurs when these conditions combine in such a way that a certain average noise intensity results in maximized information transfer. A time-averaged output due to signal of interest plus noise will yield an better measurement of the signal compared to the system's response without noise in terms of SNR; the idea of adding noise to a system in order to improve the quality of measurements is counter-intuitive.

Measurement systems are constructed or evolved to reduce noise as much as possible and thereby provide the most precise measurement of the signal of interest. Numerous experiments have demonstrated that, in both biological and non-biological systems, the addition of noise can improve the probability of detecting the signal; the systems in which stochastic resonance occur are always nonlinear systems. The addition of noise to a linear system will always decrease the information transfer rate. Stochastic resonance was first discovered in a study of the periodic recurrence of Earth's ice ages; the theory developed out of an effort to understand how the earth's climate oscillates periodically between two stable global temperature states, one "normal" and the other an "ice age" state. The conventional explanation was that variations in the eccentricity of earth's orbital path occurred with a period of about 100,000 years and caused the average temperature to shift dramatically; the measured variation in the eccentricity had a small amplitude compared to the dramatic temperature change and stochastic resonance was developed to show that the temperature change due to the weak eccentricity oscillation and added stochastic variation due to the unpredictable energy output of the sun could cause the temperature to move in a nonlinear fashion between two stable dynamic states.

As an example of stochastic resonance, consider the following demonstration after Simonotto et al. The image to the left shows an original picture of the Arc de Triomphe in Paris. If this image is passed through a nonlinear threshold filter in which each pixel detects light intensity as above or below a given threshold, a representation of the image is obtained as in the images to the right, it can be hard to discern the objects in the filtered image in the top left because of the reduced amount of information present. The addition of noise before the threshold operation can result in a more recognizable output; the image below shows four versions of the image after the threshold operation with different levels of noise variance. The quality of the image resulting from stochastic resonance can be improved further by blurring, or subjecting the image to low-pass spatial filtering; this can be approximated in the visual system by moving away from the image. This allows the observer's visual system to average the pixel intensities over areas, in effect a low-pass filter.

The resonance breaks up the harmonic distortion due to the threshold operation by spreading the distortion across the spectrum, the low-pass filter eliminates much of the noise, pushed into higher spatial frequencies. A similar output could be achieved by examining multiple threshold levels, so in a sense the addition of noise creates a new effective threshold for the measurement device. Evidence for stochastic resonance in a sensory system was first found in nerve signals from the mechanoreceptors located on the tail fan of the crayfish. An appendage from the tail fan was mechanically stimulated to trigger the cuticular hairs that the crayfish uses to detect pressure waves in water; the stimulus consisted of sinusoidal motion at 55.2 Hz with random Gaussian noise at varying levels of average intensity. Spikes along the nerve root of the terminal abdominal ganglion were recorded extracellularly for 11 cells and analyzed to determine the SNR. Two separate measurements were used to estimate the signal-to-noise ratio of the neural response.

The first was based on the Fourier power spectrum of the spike time series response. The power spectra from the averaged spike data for three different noise intensities all showed a clear peak at the 55.2 Hz component with different average levels of broadband noise. The low- and mid-level added noise conditions show a second harmonic component at about 110 Hz; the mid-level noise condition shows a stronger component at the signal of interest than either low- or high-level noise, the harmonic component is reduced at mid-level noise and not present in the high-level noise. A standard measure of the SNR as a function of noise variance shows a clear peak at the mid-level noise condition; the other measure used for SNR was based on the inter-spike interval histogram instead of the power spectrum. A