Reliability of the Medtrac MDI Chronolog Brueckner, Jennifer Wilson; Marshik, Patricia; Sherman, James ...
Journal of allergy and clinical immunology,
10/1997, Letnik:
100, Številka:
4
Journal Article
Recenzirano
Background: The Medtrac MDI Chronolog is an electronic device for monitoring adherence to metered-dose inhalers. It replaces previous models of the Nebulizer Chronolog and uses a different mechanism ...of recording actuations.
Objective: This study was carried out to determine whether the new model can accurately record and report the date, time, and number of metered-dose inhaler actuations.
Methods: Four canisters of beclomethasone (Beclovent) were discharged through four Chronologs with fresh batteries at a rate of 1, 2, 4, or 8 times twice daily for 7 days. Four additional canisters were used as controls and discharged simultaneously through the standard actuator. The weight of all canisters and Chronolog battery voltage were measured before and at the end of the 7-day experiment. The data retrieved from the Chronologs were compared with the information recorded manually during each discharge.
Results: The loss in canister weight was consistent for the number of puffs discharged from all four Chronolog units and controls. However, the accuracy of the Chronologs in recording the number of actuations varied between 50% and 100%. The largest amount of data loss occurred with the unit used to discharge 8 puffs and was associated with a dead battery at the end of the 7-day trial. For actuations that were retrievable, the Chronologs accurately recorded the date and time.
Conclusions: Unexpected battery voltage drain and other mechanical problems that we encountered may cause data loss and the false appearance of missed doses. Thus the units that we tested were not sufficiently reliable to monitor patient adherence. (J Allergy Clin Immunol 1997;100:488-91.)
Phase and element composition, electronic states, structure and tribological properties of carbon coatings doped with nitrogen were investigated in this work. Doping was carried out by deposition in ...an N
2 atmosphere and by N
+ implantation. All the coatings were found to be in an amorphous state. Tribological properties improvement was obtained (lifetime increase, friction coefficient decrease).
We present a comprehensive study of the inclusive production of $V^{0}V^{0}$ pairs ($V^{0}=\Lambda, \bar\Lambda or K_S$) by $\Sigma^-$ and $\pi^-$ of 340 GeV/c momentum and neutrons of 260 GeV/c mean ...momentum in copper and carbon targets. In particular, the dependence of the $x_F$ spectra on the combination of beam-particle and produced $V^{0}V^{0}$ pair is investigated and compared to predictions obtained from PYTHIA and QSGM calculations. The data and these predictions differ in many details, the agreement can at best be termed as qualitative. A signal from decays of the tensor meson $f'_2$(1525) was observed in the K_S K_S mass distribution and inclusive production cross sections were measured. No signal was found from the double-strange H-dibaryon decaying to $\Lambda \Lambda$.
The stress evolution on NiFe (20 wt.%) thin films with thickness of 170 nm was studied during thermal cycles up to maximal 530°C. The results are correlated to microstructural analyses carried out on ...samples cycled to various maximum temperatures by means of transmission electron microscopy, X-ray diffraction, and Auger electron spectroscopy. In addition, resistance-vs.-temperature measurements yielded more information about the microstructural evolution. The atomic rearrangement in grain boundaries is held responsible for a first irreversible stress contribution appearing between 150 and 300°C. A second, more distinct irreversible tensile stress contribution of approximately 400 MPa occurs between 300 and 400°C. It is explained by abnormal grain growth which can be observed in the same temperature range.
The development of biaxial stress in FeAl8 thin films was investigated during annealing in vacuum. The heat treatment leads to irreversible changes in the microstructure of the FeAl8 thin films, ...which were determined by stress–temperature measurements, transmission electron microscopy, and X-ray diffraction. The stress development is explained by semiquantitative considerations of atomic rearrangement (excess-vacancy annihilation, grain-boundary relaxation, and grain growth). The stress development between 180 and 400°C is affected by grain-boundary relaxation, and between 450 and 675°C by grain growth. The high thermal stability, which was measured in previous investigations, could not be confirmed.
We have measured the polarization of Λ\LambdaΛ hyperons produced inclusively by a Σ−\Sigma^-Σ− beam of 340 GeV/c momentum in nuclear targets. From a sample of 9.5 millions of identified Λ\LambdaΛ ...decays, polarizations were determined in the range xF>0.1x_F \gt 0.1xF>0.1 and pt≤1.6p_t\leq 1.6pt≤1.6 GeV/c . The polarization w.r.t. the production normal is mainly positive for xF≥0.3x_F \geq 0.3xF≥0.3. At fixed values of xFx_FxF, it increases with ptp_tpt to a maximum between pt=0.5p_t = 0.5pt=0.5 and pt=1p_t = 1pt=1 GeV/c , and then decreases to zero or even negative values, in sharp contrast to the plateau above pt=1p_t = 1pt=1 GeV/c observed in inclusive Λ\LambdaΛ production by protons.
A feasibility test of a new method to polarize beams of strongly interacting charged particles circulating in a storage ring is described. The stored particles, here protons, pass through a polarized ...hydrogen gas target (thickness 6times10sup 13 bold H/cmsup 2) in the ring some 10sup 10 times and become partially polarized because one spin state is attenuated faster than the other. The polarization buildup is clearly demonstrated in the present experiment.
We have measured the polarization of Ξ− hyperons produced inclusively by a Σ− beam of 340 GeV/c momentum in nuclear targets. From a sample of 880000 identified Ξ− decays, polarizations were ...determined in the range 0 < x F < 0.9 and pt≤1.6 GeV/c. The polarization w.r.t. the production normal is negative for xF≥ 0.3. At fixed values of x F , its magnitude increases with p t to maximum values which reach about 20% at large x F .
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