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Exercise induced bronchoconstriction (EIB) describes the acute transient airway narrowing that occurs during and most often after exercise, and is prevalent in elite athletes. Prolonged hyperventilation of dry or cold air and increased inhalation of pollutants or allergens could account for the bronchoconstrictive reaction. The subsequent airway inflammation seems to differ from typical asthma. Objective measures of lung function and provocation tests should be used for an accurate and reliable diagnosis. EIB is currently treated with inhalation of beta(2)-agonists or, as second choice, sodium cromoglycate approximately 15 min before exercise. If this proves to be insufficient then inhaled steroids should be added. Leukotriene receptor antagonists can be used in patients whose symptoms do not respond to inhaled steroids. The screening of high risk populations such as swimmers, cyclists, rowers and winter athletes is recommended by some authors. Drug doping regulations and practical recommendations for competitive athletes and their health care providers are explained.

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The use of sacrificial self-assembled monolayers (SAMs) to prepare clean n-type GaAs (100) surfaces without band bending in vacuo is demonstrated. GaAs surface passivation using octadecanethiol SAMs after HCl cleaning is shown to lead to an enhancement of the room-temperature photoluminescence intensity. Synchrotron-radiation photoelectron spectroscopy (SRPES) finds that the interfacial oxide between GaAs and the SAM remains below the detection limit. Evidence for both Ga−S and As−S bonds at the GaAs−thiolate interface is found. The limited thermal stability of the SAM allows the desorption of the alkyl chains by in situ thermal annealing at temperatures above 180 °C, leaving S bonded to Ga behind. The resulting surface contains only a very small amount of O (0.05 ML coverage) and C (about 3% of the SAM remaining) and shows no band bending with the surface Fermi level close to the conduction band. Atomic layer deposition of Al 2 O 3 on this surface occurs via the formation of Al−S bonds without introducing any additional band bending. This indicates that the surface preparation of ntype GaAs (100) using sacrificial octadecanethiol SAMs followed by in situ thermal removal provides a route toward GaAs/oxide interfaces without interfacial oxides and without band bending.