Determination of metals and trace elements in patients with total knee or hip arthroplasty with CoCrMo alloy was performed. Blood, urine and cerebrospinal fluid (CSF) samples were analyzed and compared with samples from healthy people. Levels of Co, Cr as well as Na, Ca, Fe, Zn, Se, Rb, Sb and Br were determined by means of neutron activation analysis. The values of Cr and Co of the blood and urine measurements were elevated in patients with replacement, and according to the statistical analysis, significant differences of the elements Zn, Br, Co and Sb were found in the CSF (p?<?0.05).
In set theory without the Axiom of Choice ( ), we investigate the problem of the placement of ?o?'s Theorem ( ) in the hierarchy of weak choice principles, and answer several open questions from the book Consequences of the Axiom of Choice by Howard and Rubin, as well as an open question by Brunner. We prove a number of results summarised in § 3. 相似文献
With nine examples, we seek to illustrate the utility of the Renormalization Group approach as a unification of other asymptotic and perturbation methods. 相似文献
Mathematische Zeitschrift - We prove a sharp integral inequality for the dyadic maximal function of $$\phi \in L^p$$ . This inequality connects certain quantities related to integrals of $$\phi $$... 相似文献
Aspects of dense lignite–water slurries (LWS) rheology were investigated using controlled stress and controlled strain rheometers
with parallel disks and Couette geometries. During the preparation of the slurries, the achieved solids volume fractions were
up to 0.425 and the particle size distributions were polydispersed with sizes up to 300 μm. In the ascending parts of consecutive
flow loops, a slope transition of the flow curve was observed and studied in relation to the solids volume fraction. The obtained
results with the different geometries and rheometers were qualitatively the same. By following the model proposed by Cheng
(Rheol Acta 42:372–382, 2003) for thixotropic fluids, and taking into account the yield stress appearance, a suitable correlation for LWS is proposed,
which is consistent with the experimental flow curves. 相似文献
An investigation of the rheological properties of dense lignite-water suspensions is reported here in order to evaluate the
parameters that affect the rheology of these suspensions. Different types of particle size distributions were achieved via
wet grinding with particle sizes down to 1 μm. Polyelectrolytes and surfactants were used to improve the stability and rheology
of suspensions. The achieved solid volume fraction, φ, with acceptable rheological behavior was 0.45, while the ratio of φ/φm was close to 0.85; φm is the maximum solid volume fraction. Various types of flow tests were performed on lignite-water suspensions with various
preshear times and stress levels. Typical shear rates varied in the range between 10–2 to 102 s–1. The low shear behavior was found to be quite different from the high shear behavior for the most concentrated suspensions,
with a plateau value at low shear rates indicating the appearance of a yield stress. These plateau values, however, depend
on shear history, which is responsible for the development of different structures in the sample. The viscosity curves corresponding
to the ascending and descending parts of the flow curve were found to be different; these flow curve parts can be described
either by well established models or by modified ones. The non-Newtonian time dependent behavior of the lignite-water suspensions
is attributed to the high value of the ratio φ/φm, the polydispersity of the particle size distribution, and the non-spherical shape of the lignite particles. 相似文献
In the framework of ZF, i.e., Zermelo-Fraenkel set theory without the axiom of choice AC, we show that if the family of all non-empty, closed subsets of a metric space has a choice function, then so does the family of all non-empty, open subsets of . In addition, we establish that the converse is not provable in ZF.
We also show that the statement ``every subspace of the real line with the standard topology has a choice function for its family of all closed, non-empty subsets" is equivalent to the weak choice form ``every continuum sized family of non-empty subsets of reals has a choice function".