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101.
R Coninx GE Pfyffer C Mathieu D Savina M Debacker F Jafarov I Jabrailov A Ismailov F Mirzoev R de Haller F Portaels 《Canadian Metallurgical Quarterly》1998,316(7142):1423-1425
Tuberculosis is a significant health problem in Azerbaijan. In prisons, this problem is compounded by overcrowding, poor general health, a high representation of risk groups, late case finding, and incomplete treatments. The present study investigated the extent of drug resistance at the Central Penitentiary Hospital in Baku--the country's only treatment center for prisoners with tuberculosis. This International Committee of the Red Cross program, established in 1995, uses the directly observed treatment, short course (DOTS) strategy. Sputum samples were collected from two groups of prisoners: 1) 28 patients who failed to respond, clinically or bacteriologically, after a minimum of 8 weeks to the treatment regimen recommended by the World Health Organization and 2) 38 patients consecutively enrolled over a 4-week period from whom sputum was taken before the start of treatment. Mycobacterium tuberculosis was isolated from all 66 sputum specimens. In the first group, 25 strains (98%) were multidrug resistant (to rifampicin and isoniazid). Such resistance occurred in all new cases and 14 (82%) of the 17 failure or relapse cases. In the second group, 9 strains (24%) were multidrug resistant and only 12 (32%) were fully susceptible. This resistance was found in 3 strains (15%) among the 20 new cases and in 6 strains (33%) among the 18 cases of treatment failure or relapse. These findings suggest that prisoners may have an important future role in the transmission of tuberculosis, especially multidrug resistant forms, in the former Soviet Union. 相似文献
102.
E. Boidy A. Bouvard F. Pellet 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2002,17(4):415-424
This paper presents a back analysis of the time-dependent behaviour of a monitored tunnel in Switzerland. It concerns a specific section of the Mont Terri reconnaissance gallery which was excavated in creeping rock. From a theoretical point of view, Lemaitre's viscoplastic model was implemented in the FLAC 2D finite-difference numerical code. Particular attention was paid to the stability of the numerical solution for such an explicit mode of resolution. Lemaitre model parameters were successfully fitted on creep tests and then on in situ convergence measurements after a complete numerical simulation. Based on the comparison of strain and stress measured in the lining with the calculated values, time-dependent behaviour can finally be extrapolated over a period of approximately 10 years. Scale effects between results of in situ and laboratory fittings are also discussed. The aim of these investigations is to justify the interest of Lemaitre's model for the analysis of time-dependent behaviour of underground structures over a long period of time. 相似文献
103.
The microstructure and the corrosion behaviour of high pressure die-cast and semi-solid cast AZ91D magnesium alloys have been investigated. Semi-solid processing leads to a structure with large rounded grains of a solid solution of magnesium (α phase) whereas die-cast alloys are more homogeneous. Electrochemical measurements, particularly with impedance spectroscopy, have shown that the semi-solid cast alloy possesses a corrosion rate at least 35% below that of the die-cast alloy. This can be explained with considering the differences between the composition of the primary α phase and the volume fraction of the β phase, in the two types of alloy. 相似文献
104.
105.
When dealing with optimal control problems to maximize the selectivity of reactions for fine chemical synthesis, representative kinetic and thermodynamic models should be available. While literature appears to be very extensive on theoretical approaches to solve the problem, examples presenting complete models of chemical transformations are scarce. This paper presents the identification of consecutive reactions carried out in a batch reactor. Material and energy balances, satisfying dynamical state evolutions in the temperature range 20-60°C are deduced, for concentrations of acrylonitrile ranging up to 1.6 kmol·m?3. The stoichiometric network is simplified into two reactions, one reversible and one irreversible. Reaction enthalpies are measured from isothermal runs conducted in the RC1 heat-flow calorimeter from Mettler Toledo. 相似文献
106.
The relative motion of the electron-hole pairs which constitute Wannier-Mott excitons in semiconductor quantum wells, superlattices, and quantum wires can never be considered strictly 1-D, 2-D, or 3-D. We propose an exact generalization of the well-known calculations of Elliott in the 3-dimensional case, and of Shinada and Sugano for 2-dimensional media-we calculate the absorption spectrum by bound and unbound excitonic states, by using a metric space with a noninteger dimension α>1. Whatever the dimensionality, i.e., for any quantum-sized structure, the whole optical density spectrum is obtained from a single compact equation, in excellent agreement with experimental data and with the most accurate available theories. We present examples of calculated spectra for quantum wells under applied perpendicular electric fields, and for quantum wires 相似文献
107.
P Djiane M Bory S Djurakdjian F Houel J Leonetti P Mathieu C Mercier 《Canadian Metallurgical Quarterly》1976,26(25):1833-6, 1841-4
108.
P Cuisnier-Gleizes M Thomasset F Sainteny-Debove H Mathieu 《Canadian Metallurgical Quarterly》1976,20(3):235-249
Sham-operated and parathyroidectomized (PTX) rats were divided into two pair-fed groups, one on a normal mineral intake (0.5% Ca, 0.3% P), the other on a regimen low in phosphorus (0.5% Ca, 0.03% P). P depletion led to a drop in plasma P and urine P, a rise in plasma Ca and a marked rise in urine Ca, a drop in serum magnesium and a rise in urine Mg. The changes were more pronounced in the PTX animals, but final values were the same in both groups. Parallel bone-seeking isotope (85Sr, 177Lu, 237Np) studies in nonablated animals revealed an increase in the urinary nuclide output and in the urine/tibia ratio in P-deficient animals. Normal and primary bone osteocytes decreased and enlarged osteocytes increased as a result of P deficiency; osteoclasts and osteoblasts also increased. Bone composition showed a drop in ash content and a rise in water, with a light decrease in both Ca and P, and a corresponding rise in hydroxyproline and nitrogen in the P-deficient animals. The results are interpreted to mean that P-deficiency in the young growing rat leads to an increase in bone resorption which occurs also in the absence of parathyroid hormone (PTH). The fact that final values were similar in the control and PTX P-deficient animals suggests that steady-state regulation can also occur without PTH. Because P-deficiency leads to rapid hypercalcemia and rapid marked hypercalciuria, there may exist a mechanism for phosphate regulation which would then supersede Ca homeostasis. The change in serum and urine Mg levels may reflect a decrease in tubular Ca and Mg reabsorption associated with P-deficiency. 相似文献
109.
Par R. Perron A. Mathieu C. Paquot 《European Journal of Lipid Science and Technology》1966,68(7):530-535
New Differential Thermo Analysis Apparatus for the Testing of Organic Substances The authors describe, a new heating and regulating apparatus for the differential thermo analysis of organic substances in a range of ?100° to +300°C. The apparatus has a contact thermometer whose range can be changed by a right-left changeable synchronmotor. The heating capacity is changed with an automatically controlled regulating transformer which receives the regulating impulses apart from a contact thermometer from a R-C-part as well. It is therefore possible to divide heating and cooling in separate time and thermal steps. Again the control gives the amount of correction for the regulation of heating so that the reproducible thermal and time cycles are run which permit the accurate analysis of, for example, the transformation points of the triglycerides. Along with the circuit diagram and a functional diagram, two examples of thermograms taken with this apparatus are given. 相似文献
110.