598 research outputs found
Asthma treatment in children: A guide to screening for and management of hypothalamic-pituitary-adrenal axis suppression
A recently published approach to paediatric asthma management neither recommended screening for nor suggested any management of hypothalamic-pituitary-adrenal axis suppression in asthmatic children treated with corticosteroids. The existing literature on this topic was therefore reviewed and the quality of the evidence assessed. Recommendations for diagnosis, screening and management are made utilising the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach
Phase-modulated standing wave interferometer
Standing wave interferometers (SWIs) show enormous potential for miniaturization because of their simple linear optical set-up, consisting only of a laser source, a measuring mirror and two standing wave sensors for obtaining quadrature signals. To reduce optical influences on the standing wave and avoid the need for an exact and long-term stable sensor-to-sensor distance, a single-sensor set-up was developed with a phase modulation by forced oscillation of the measuring mirror. When the correct modulation stroke is applied, the harmonics in the sensor signal can be used for obtaining quadrature signals for phase demodulation and direction discrimination
Heterodyne standing-wave interferometer with improved phase stability
This paper describes a standing-wave interferometer with two laser sources of different wavelengths, diametrically opposed and emitting towards each other. The resulting standing wave has an intensity profile which is moving with a constant velocity, and is directly detected inside the laser beam by two thin and transparent photo sensors. The first sensor is at a fixed position, serving as a phase reference for the second one which is moved along the optical axis, resulting in a frequency shift, proportional to the velocity. The phase difference between both sensors is evaluated for the purpose of interferometric length measurements
Hypertriglyceridaemia in adolescents may have serious complications
Acute pancreatitis is an often-overlooked cause of acute abdominal pain in children and adolescents. Severe hypertriglyceridaemia is an important cause of recurrent acute pancreatitis. Monogenic causes of hypertriglyceridaemia, such as familial chylomicronaemia caused by lipoprotein lipase deficiency, are more frequently encountered in children and adolescents, but remain rare. Polygenic hypertriglyceridaemia is more common, but may require a precipitant before manifesting. With the global increase in obesity and type 2 diabetes, secondary causes of hypertriglyceridaemia in children and adolescents are increasing. We report two cases of severe hypertriglyceridaemia and pancreatitis in adolescent females. Hypertriglyceridaemia improved markedly with restriction of dietary fat. An inhibitor to lipoprotein lipase was found to be the cause in one patient, while in the other limited genetic investigation excluded chylomicronaemia owing to deficiency of lipoprotein lipase, its activators and processing proteins
Cyclotron resonance of the quasi-two-dimensional electron gas at Hg1-xCdxTe grain boundaries
The magnetotransmission of a p-type Hg0.766Cd0.234Te bicrystal containing a single grain boundary with an inversion layer has been investigated in the submillimetre wavelength range. For the first time the cyclotron resonance lines belonging to the various electric subbands of a quasi-two-dimensional carrier system at a grain boundary could be detected. The measured cyclotron masses and the subband densities determined from Shubnikov-de Haas experiments are compared with theoretical predictions and it is found that the data can be explained very well within the framework of a triangular well approximation model which allows for non-parabolic effects
Proximal oesophageal strictures in a child with HIV disease
The patient and her twin brother were born preterm by caesarean section. Her birth weight was 2 100 g. She had perinatal exposure to HIV, and was therefore bottle-fed with term formula milk.She remained well until the age of 11 months when, weighing 6 880 g, she required hospital admission for a right upper lobe pneumonia, which responded well to oral amoxicillin. No causative organism was isolated. There was no evidence of active tuberculous infection on gastric washings or Mantoux test
N-Electron Giant Dipole States in Crossed Electric and Magnetic Fields
Multi-electron giant dipole resonances of atoms in crossed electric and
magnetic fields are investigated. Stationary configurations corresponding to a
highly symmetric arrangement of the electrons on a decentered circle are
derived, and a normal-mode and stability analysis are performed. A
classification of the various modes, which are dominated by the magnetic field
or the Coulomb interactions, is provided. Based on the MCTDH approach, we carry
out a six-dimensional wave-packet dynamical study for the two-electron
resonances, yielding in particular lifetimes of more than 0.1 s for strong
electric fields.Comment: 37 pages, 22 figs. (plus subfigures
Determination of the mixing ratio of a flowing gas mixture with self-actuated microcantilevers
Microcantilevers offer a wide range of applications in sensor and measurement technology. In this work cantilever sensors are used as flow sensors. Most conventional flow sensors are often only calibrated for one type of gas and allow an analysis of gas mixtures only with increased effort. The sensor used here is a cantilever positioned vertically in the flow channel. It is possible to operate the sensor in dynamic and static mode. In the dynamic mode the cantilever is oscillating. Resonance frequency, resonance amplitude and phase are measured. In static mode, the bending of the cantilever is registered. The combination of the modes enables the different measured variables to be determined simultaneously. A flow influences the movement behaviour of the sensor, which allows the flow velocity to be deduced. In addition to determining the flow velocity, it is also possible to detect different types of gas. Each medium has certain properties (density and viscosity) which have different effects on the bending of the sensor. As a result, it is possible to measure the mixing ratio of a known binary gas mixture and their flow velocity simultaneously with a single sensor. In this paper this is investigated using the example of the air–carbon-dioxide mixture
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