In 15–20% of active cases, the infection spreads outside the lungs, causing other kinds of TB. These are collectively denoted as "extrapulmonary tuberculosis". Extrapulmonary TB occurs more commonly in immunosuppressed persons and young children. In those with HIV, this occurs in more than 50% of cases. Notable extrapulmonary infection sites include the pleura (in tuberculous pleurisy), the central nervous system (in tuberculous meningitis), the lymphatic system (in scrofula of the neck), the genitourinary system (in urogenital tuberculosis), and the bones and joints (in Pott disease of the spine), among others. When it spreads to the bones, it is also known as "osseous tuberculosis", a form of osteomyelitis. Sometimes, bursting of a tubercular abscess through skin results in tuberculous ulcer. An ulcer originating from nearby infected lymph nodes is painless, slowly enlarging and has an appearance of "wash leather". A potentially more serious, widespread form of TB is called "disseminated tuberculosis", also known as miliary tuberculosis. Miliary TB makes up about 10% of extrapulmonary cases.
At least what percentage of HIV-positive patients who contract TB will experience extrapulmonary infection?
50%

Spirometry is recommended to aid in diagnosis and management. It is the single best test for asthma. If the FEV1 measured by this technique improves more than 12% following administration of a bronchodilator such as salbutamol, this is supportive of the diagnosis. It however may be normal in those with a history of mild asthma, not currently acting up. As caffeine is a bronchodilator in people with asthma, the use of caffeine before a lung function test may interfere with the results. Single-breath diffusing capacity can help differentiate asthma from COPD. It is reasonable to perform spirometry every one or two years to follow how well a person's asthma is controlled.
Why is spirometry so commonly used to diagnose asthma?
It is the single best test for asthma

Buses now provide the majority of local public transport. The main bus operators are First Southampton and Bluestar. Other operators include Brijan Tours, Stagecoach and Xelabus. The other large service provider is the Uni-link bus service (running from early in the morning to midnight), which was commissioned by the University of Southampton to provide transport from the university to the town. Previously run by Enterprise, it is now run by Bluestar. Free buses are provided by City-link'. The City-link runs from the Red Funnel ferry terminal at Town Quay to Central station via WestQuay and is operated by Bluestar. There is also a door-to-door minibus service called Southampton Dial a Ride, for residents who cannot access public transport. This is funded by the council and operated by SCA Support Services.
What bus service did the University of Southampton commission to carry people between the city and the university?
Uni-link