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1.
2.
Viviane Van Hoof Hugo Cluckers Vera Verhaeghe An Hennebel Marleen Truyens Edith Van Loock Pierre Rombouts Dirk Maes Jan Van Elven Katrien Lesage Mark Flothmann Lieve Nijs Filip Colpaert Werner Vercammen Dominique Bolain 《Accreditation and quality assurance》2004,10(1-2):55-59
In response to a change of the Belgian National Directives whereby hospital laboratories became responsible for all point-of-care testing (POCT) performed within hospital walls a standardized and automated POC glucose-testing system was implemented in our hospital. The system consists of 50 AccuCheck Inform instruments (Roche Diagnostics, Vilvoorde, Belgium), 50 docking stations, a DataCare Server, and connections to the medical laboratory information system (MOLIS, Sysmex, Barchon, Belgium) and to the hospital information system. Implementation involved many parties and extensive preparation and communication. Key issues were bar-coded patient and user identification, training, and responsibilities. One year after the hospital wide implementation of this system the quality of POC glucose testing has significantly increased, thereby improving patient safety. This study describes a stepwise change over involving the medical laboratory and with a focus on hands-on quality.Presented at the ninth conference on Quality in the Spotlight, 18–19 March 2004, Antwerp, Belgium. 相似文献
3.
L. V. Giurgiu M. N. Grecu X. Filip O. Raita Al. Darabont D. Gavre J. Blasco 《Applied magnetic resonance》2003,24(3-4):351-360
We report an electron paramagnetic resonance (EPR) investigation of the spin dynamics in the paramagnetic regime of the colossal magnetoresistive manganites La2/3Ca1/3Mn1?x Me x O3 (Me=Al, In;x≤0.05). The temperature dependences of the EPR linewidth and integral intensity have been analyzed in terms of the bottleneck spin relaxation and small-polaron hopping models. The exchange coupling integral between Mn3+ and Mn4+ ions and the polaron activation energy decrease with increasing doping level. A discussion is given concerning the factors which could explain the observed changes. 相似文献
4.
M. E. Kompan I. I. Novak V. B. Kulik 《Journal of Experimental and Theoretical Physics》2002,94(4):739-744
Spectra of second-order Raman scattering in porous silicon are investigated. A band shift towards lower energies in second-order spectra is observed, as well as the correlation between the values of band shift in first-and second-order spectra. It is demonstrated that the observed effect cannot be interpreted using the conventional concepts of the mechanisms of scattering in microcrystalline samples. An interpretation of the revealed effect is suggested. 相似文献
5.
The presented work offers new algorithms for phase evaluation in interferometric measurements. Several phase-shifting algorithms with an arbitrary but constant phase-shift between captured intensity frames are proposed. These phase calculation algorithms need to measure five frames of the intensity of the interference field. The algorithms are similarly derived as so called Carré algorithm. The phase evaluation process then does not depend on the linear phase shift errors. Furthermore, the detailed analysis of the algorithms with respect to most important factors, which affect interferometric measurements, is carried out. It is also studied the dependency of the evaluation algorithms on the phase shift values, and the proposed phase calculation algorithms are compared with respect to the resulting phase errors. The influence of most important factors in the measurement and evaluation process was simulated as systematic and random errors using a proposed mathematical model. 相似文献
6.
7.
Erich Novak 《Numerische Mathematik》1986,50(2):245-252
Summary The definition of the average error of numerical methods (by example of a quadrature formula
to approximateS(f)= f d on a function classF) is difficult, because on many important setsF there is no natural probability measure in the sense of an equidistribution. We define the average a posteriori error of an approximation
by an averaging process over the set of possible information, which is used by
(in the example of a quadrature formula,N(F)={(f(a
1), ...,f/fF} is the set of posible information). This approach has the practical advantage that the averaging process is related only to finite dimensional sets and uses only the usual Lebesgue measure. As an application of the theory I consider the numerical integration of functions of the classF={f:[0,1]/f(x)–f(y)||x–y|}. For arbitrary (fixed) knotsa
i
we determine the optimal coefficientsc
i
for the approximation
and compute the resulting average error. The latter is minimal for the knots
. (It is well known that the maximal error is minimal for the knotsa
i
.) Then the adaptive methods for the same problem and methods for seeking the maximum of a Lipschitz function are considered. While adaptive methods are not better when considering the maximal error (this is valid for our examples as well as for many others) this is in general not the case with the average error. 相似文献
8.
Infrared and Raman spectra of solid magnesium bromide dietherate MgBr22Et2O have been studied at different temperatures between 300 and 90 °K in the 4000 to 30 cm? range. Infrared spectra of this compound at various pressures up to 10 kbar have also been investigated. The MgBr22Et2O crystal has two phases and there is a reversible transition between them. This phase transition concerns primarily the conformational change of (C2Hg5)2O molecules and much less the arrangement of the ligands around the central magnesium atom. At room temperature or low pressure the GG conformation appears to be predominant while at low temperature or high pressure there is only TG (or TT) conformation of ether molecules. The enthalpy difference and transition temperature between the phases have been determined calorimetrically. An assignment of the spectra of both phases is given. The analysis of intramolecular vibrations gives information about the relative contribution of conformational change and coordination effect to the frequency shifts of (C2H5)2O vibrations. The assignment of magnesium-ligand vibrations on the other hand allows us to estimate the Mg-Br and Mg-O force constants. 相似文献
9.
Remarkably stable mesoionic oxazolones possessing an oxazolo[3,2-a]quinolinium structure (5a–b),8,16, 17) were obtained by the double cyclisation of phenylglycine-o-carboxylic acids (3a–c) in refluxing acetic anhydride or in benzoic anhydride at 140°, The 0-Ac group was eliminated to give the corresponding lactones (6a–b) or replaced by O-Ts (7). IR stretching vibrations of the endo-carbonyl were in the range 1710–1768 cm?1, while v1-CH exhibited unusually high values (3159–3194 cm-1). 1-Acyl derivatives could be obtained only with TFAA (23–24), although easy deuteration of the same position took place in the presence of traces of trifluoroacetic acid. Hydrolysis of 5b led to the α-quinolone-N-acetic acid 27a. In the case of 5a, hydrolysis was accompanied by self-acylation of the nucleophilic site at C-4 with formation of a dimeric acid 28a. The presence of an additional Me group in phenylalanine-o-carboxylic acid (36) activates the corresponding mesoionic oxazolone 37 so that 1-acylation becomes possible with formation of the fused oxazole 38 by the Dakin-West reaction. Temperature dependent magnetic non-equivalence of methylene protons has been observed in acids 3b-d and f and also in the 7-membered anhydride 48b. 相似文献
10.
Filip Fratev Gottfried Olbrich Oskar E. Polansky 《Monatshefte für Chemie / Chemical Monthly》1979,110(3):505-515
UsingGleason's theorem the pars orbital concept is developed for excited states of conjugated systems described by CI-methods. A significance index is introduced to evaluate different patterns of fragmentation. The usefulness of this approach is illustrated for butadiene, biphenyl, naphthalene, and azulene.
11. Mitt.:H. Karpf, O. E. Polansky undM. Zander, Tetrahedron Lett.1978, 2069. 相似文献