Valley Parade, known as the Utilita Energy Stadium for sponsorship reasons, is an all-seater football stadium in Bradford, West Yorkshire, England. Built in 1886, it was the home of Manningham Rugby Football Club until 1903, when they changed code from rugby football to association football and became Bradford City, it has been Bradford City's home since, although it is now owned by former chairman Gordon Gibb's pension fund. It has been home to Bradford for one season, Bradford Bulls rugby league side for two seasons, as well as host to a number of England youth team fixtures. Football architect Archibald Leitch was commissioned to redevelop the ground when Bradford City were promoted to the First Division in 1908; the stadium underwent few changes until the fatal fire on 11 May 1985, when 56 supporters were killed and at least 265 were injured. It underwent a £2.6 million redevelopment and was re-opened in December 1986. The ground underwent significant changes in the 1990s, early 2000s, now has a capacity of 25,136.

The record attendance of 39,146 was set in 1911 for an FA Cup tie against Burnley, making it the oldest surviving attendance record at a Football League ground in the country. The highest attendance at Valley Parade, as it is now, was against Reading in the 2015 FA Cup Quarter-finals. Manningham Rugby Football Club, formed in 1876 played games at Cardigan Fields, in the Carlisle Road area of Bradford; when their ground was sold to facilitate the construction of Drummond School, the club required a new home. They bought one-third of the Valley Parade site in Manningham, taking a short-term lease out on the rest of the land in time to play there for the 1886–87 season; the new ground and the road it was built upon both adopted the name of the local area, Valley Parade, a name deriving from the steep hillside below Manningham. The land was a quarry, formed part of a greater site owned by Midland Railway Company; the club spent £1,400 appointing designers to oversee the excavation and levelling of the land, moved a one-year-old stand from Carlisle Road to the highest part of the new ground.

The original ground comprised the relocated stand, a 2,000-capacity stepped enclosure with the players' changing rooms beneath the stand, the playing area, a cinder athletics track and fencing to limit the total capacity to 18,000. The playing field was made of ballast, ashes and sods; the ground was opened on 27 September 1886 for a game against Wakefield Trinity, watched by a capacity crowd, but construction work meant most of Manningham's early games were away fixtures. On Christmas Day 1888, 12-year old Thomas Coyle was killed at the ground when the barrier under which he was sitting collapsed on him breaking his neck. An inquest decided the death was accidental and the accident happened due to the weight of spectators leaning on the barrier; the takings from the game totalling £115 were distributed to Coyle's family and the families of other boys injured in the incident. Manningham RFC continued playing until 1903, when financial difficulties, caused by relegation at the turn of the century, prompted club officials to change codes from rugby football to association football.

The first association football game to be played at Valley Parade was a promotional fixture on 6 April 1903 between a side of West Yorkshire footballers and Sheffield United's 1903 FA Cup winning side. The game attracted 8,000 fans; the new football club, Bradford City, were elected to The Football League's Division Two the following month. Bradford City's first game at Valley Parade came on 5 September 1903 against Gainsborough Trinity, drawing a crowd of 11,000; as a result of alterations first implemented in 1897, City players changed in a shed behind one end of the ground, visiting teams used the old rugby club dressing rooms at the back of the nearby Belle Vue Hotel. However, after City's 5–1 defeat by Manchester United on 10 February 1906, United player Bob Bonthron was attacked as he left the ground; as a result, The Football Association closed the ground for 14 days, ordering City to switch its changing rooms to the nearby Artillery Barracks for the 1906–07 season. Several supporters faced criminal proceedings for the incident.

After Bradford City won the Division Two championship in 1907–08, the club hurried through a reconstruction programme of the ground to prepare for the club's first season in Division One. Football architect Archibald Leitch was commissioned to design new terracing in the paddock—a standing area in front of the 5,300-seater main stand, built in 1908—and build a Spion Kop at the north side of the ground and an 8,000-capacity stand at the Midland Road end opposite the main stand. Further work was performed to lower the railings, erect barriers, move the pitch and add extra turnstiles; the changing rooms were moved, with a tunnel leading from the rooms underneath the Kop along the main stand side of the ground. The total project cost £9,958, raised the capacity to 40,000; the work was not completed until midway through the 1908–09 season. The first match after work was finished took place on Christmas Day 1908, when 36,000 fans saw City host Bristol City; the improvements allowed Bradford City to set their record attendance of 39,146 on 11 March 1911 against Burnley during the club's FA Cup winning run.

It is the longest surviving attendance record at any league ground in the country. On 17 March 1932, Bradford City paid Midland Railway Company £3,750 for the remaining two-thirds of the site to become outright owners of the ground, now 45 years old; the stadium had remained unchanged since 1908, did so until 1952, when the capacity of the ground was reduced after

The von Kries coefficient law in color adaptation describes the relationship between the illuminant and the human visual system sensitivity. The law accounts for the approximate color constancy in the human visual system, it is the oldest and most used law to quantify color adaptation, is used in the field of vision and chromatic adaptation. The von Kries coefficient law compensates for the illumination change using a purely diagonal scaling of the cone absorptions. While the law does not provide a precise indication of the correction, it provides a reasonable approximation; the von Kries coefficient law built upon theories and research done by Hermann von Helmholtz. A German physicist and physician, Helmholtz asserted that “the nervous substance in question is less sensitive to reacting light falling on it than the rest of the retina, not stimulated”. Helmholtz, along with Thomas Young, proposed the trichromatic theory, or the Young–Helmholtz theory, that stated that the retina contains three types of cones, which respond to light of three different wavelengths, corresponding to red, green, or blue.

Activation of these cones in different combinations and to different degrees results in the perception of other colors. While von Kries and the other researchers did not have the means to test out the results of his stated law, others tested out his coefficient law by estimating the eigenvectors of the measured linear transformations. Many researchers, including Eileen Wassof, Burnham et al. and Macadam rejected his law as being insufficiently accurate. There were reported systematic discrepancies between prediction and experiment; the law assumes that although the responses of the three cone types are affected differently by chromatic adaptation, the spectral sensitivities of each of the three cone mechanisms remains unchanged. Therefore, if one of the three cones are less stimulated than the others, the sensitivity is proportionally reduced; the specific amount that this number is reduced by is inversely related to the relative strengths of activation by the energy distribution of the particular light in question.

The von Kries coefficient law can be expressed by the following equations: R c = R α G c = G β B c = B γ, where R c, G c, B c are the cone responses of the same observer, R, G, B are all cone responses of the same observer. Α, β, γ are the von Kries coefficients corresponding to the reduction in sensitivity of the three cone mechanisms due to chromatic adaptation. If R w r, G w r, B w r are defined as the cone responses for the reference white under the reference and test illuminants, R w, G w, B w are cone responses for the test illuminants R R w = R c R w r G G w = G c G w r B B w = B c B w r Using these to solve for the coefficients, we get: α = R w r R w β = G w r G w γ = B w r B w This law holds for the color space of the cones, although it has been proven applicable to other color spaces. Many studies have been conducted to study the applicability of the law. Most studies conclude that the law is a general approximation that cannot take into account all of the specificity needed to get a precise answer.

Wirth, in research done from 1900 to 1903, demonstrated through his studies that the law can be considered “nearly valid for reacting lights that are not too weak”. The theory on sensitivity and reacting light was evaluated and emphasized by Wright in 1934 studies, where he stated, “Now suppose R’, G’, B’ are hypothetical stimuli that produce responses along A, B, C,… three independent set of fibers to the brain. A reduction in sensitivity produced by light adaptation will, for a test colour that stimulates A alone, produce an intensity depression of R’ but no co

Kingsley Green is a mental health and learning disability site located in Hertfordshire, just southeast of the village of London Colney. Located on Harper Lane, the facility was known as Harperbury Hospital for 61 years and has been a fixture of the area's mental health scene since 1928, it had two sister institutions, Shenley Hospital and Napsbury Hospital, within a few miles of its location. A scaling down process began in the 1970s, resulted in many of the old hospital's buildings becoming abandoned. By late 2001 Harperbury had only about 200 patients and the hospital was closed; the new Kingsley Green mental health facility opened on the site in May 2009. The Royal Flying Corps, who were based at the London Colney aerodrome, used the site as an aircraft storage facility during the First World War. In 1924 Middlesex County Council purchased Porters Park Estate, totaling 420 acres to create both the Harperbury and Shenley hospitals. On 25 October 1928, the new mental hospital started operations as the Hangers Certified Institution named after the three remaining aerodrome hangers on the site.

The first patients were eight males who were put to the task of cleaning out the hangers, which were converted into wards for use by more patients. Soon eighty-six male patients worked on the site. A series of new buildings were designed by WT Curtis and the construction, undertaken by constructed by John Laing & Son, commenced in 1929; the first of these new buildings opened in February 1931 and the institution housed 342 male patients by December 1931. Various additional buildings were built to provide for the daily operation of the complex. Dormitory buildings were built for the patients and the De Salis Recreational Hall was built to seat 700 people. A building to house nurses was built west of the administration building. Tennis courts and sports grounds were built; when the complex was completed in 1936, it accommodated male and pediatric patients. It is said at times 700 persons. Once the new buildings were completed, the institution was renamed Middlesex Colony in May 1936, when the facility was opened by Minister of Health Sir Kingsley Wood.

Middlesex Colony was designed to house about 1,354 patients. Middlesex Colony was intended to be as self-sufficient as possible, with the desire that patients capable of working would work at various tasks. Many of the male patients provided the labour for the farming ventures of the institution. Fruits and vegetables were raised and cattle and chickens were raised. Milk was sold to Shenley Hospital. Men worked in workshops to provide needed goods for the hospital, such as clothes, shoes and upholstery, they performed carpentry. Female patients helped keep the wards clean. Pediatric patients were given duties. A school was built for the children; when the Second World War started, Middlesex Colony had 1,194 patients. In 1948 Middlesex Colony passed from control of the county council to control of the National Health Service; the territory around the institution fell under the jurisdiction of Hertfordshire County. Two years the institution was renamed Harperbury Hospital. During the 1950s Harperbury had 1,464 beds.

An annex at Hemel Hempstead had thirty more beds. The 1950s saw continued expansion at Harperbury. Four more patient villas were built. A department of clinical psychology was established to better assess mental handicaps; the school for pediatric patients was enlarged and an indoor swimming pool was built. In 1960 a cerebral palsy unit opened at Harperbury, it provided services to mental health units throughout the area, as well as at Harperbury. When Minister of Health Enoch Powell visited in 1961, he questioned the future role of large mental hospitals. Overcrowding at Harperbury was becoming a problem. By 1964 severe overcrowding had become severe; the hospital was intended to accommodate 1,354 patients, but in fact had 1,587 patients. Beds were packed so together, that sometimes nurses had problems reaching patients who needed emergency care. In spite of overcrowding, Harperbury continued to expand. In 1965 the Kennedy-Galton Centre opened to study clinical genetics and to diagnose chromosomal abnormalities in the unborn.

In 1969 an activity centre was opened to provide a stimulating environment for patients. Up to 1973 Harperbury's expansion continued. Changes were made to use existing space better to ease overcrowding. Sometimes this involved remodeling areas; the activity centre was expanded in 1973 and a new playground was added. By the early 1970s patients were taking part in day trips to visit the shopping areas at nearby St Albans. Patients were encouraged to take better care of their appearance and they were encouraged to participate in sports events at the hospital and to take part in various rehabilitation groups. Musical events were held at Harperbury and handicapped deaf patients were taught the Makaton sign language; the wards were redecorated. Following the introduction of Care in the Community in the early 1980s, plans were introduced to close the Shenley and Harperbury hospitals. Patients were moved out of all three hospitals. However, in 1995 and 1998 Harperbury received a temporary influx of patients as the other two institutions closed.

By late 2001 Harperbury had only about 200 patients and the old hospital was closed. The scaling down at Harperbury resulted in many of the old hospital's buildings becoming abandoned. In many cases much material and equipment were salvaged from the old buildings. Over the years most of the abandoned bu