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101.
In the female mouse, dapsone (50-500 mg kg-1, p.o.) caused a dose-related methaemoglobinaemia which peaked at 0.5-1 h with recovery to baseline values occurring by 4 h. Cimetidine (100 mg kg-1, p.o.), a known inhibitor of several hepatic P450 isozymes administered 1 h before dapsone, prevented the methaemoglobinaemia. In-vitro, dapsone required activation by mouse hepatic microsomes to cause methaemoglobin formation in mouse erythrocytes and cytotoxicity to human mononuclear leucocytes. In both instances, the toxic effects were markedly reduced by cimetidine. Daily dosing of mice with dapsone (50 mg kg-1, p.o.) for 3 weeks induced a blood dyscrasia, characterized by a fall of platelet and white blood cell counts, which was inhibited by cimetidine (100 mg kg-1, p.o. daily). It is concluded that an active metabolite of dapsone arising from a P450-dependent pathway is involved in the genesis not only of the methaemoglobinaemia but also the blood dyscrasia arising from repeated administration of the drug in this species.  相似文献   
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Metal droplet losses in slags are an important issue in copper industry. One significant aspect that promotes the entrainment of metal droplets in the slag is their attachment to spinel solids. In the present study, the wetting behaviour of copper alloys on spinel substrates has been investigated in the presence and absence of a slag phase. At first, the attachment was investigated using a synthetic slag containing spinel particles. Microstructural analysis of quenched slag reveals the presence of microdroplets sticking onto a surface of the spinel particles. Second, the metal–spinel interaction was investigated using the sessile drop technique. Wetting angle measurements were performed between Cu–Ag alloys and MgAl2O4 substrates. A non-wetting behaviour between the alloys and substrates was observed. The results suggest that the oxygen partial pressure and the amount of Ag in the alloy both influence the wetting behaviour.  相似文献   
103.
    
The innovation potential is high for bulk nanostructured materials (BNM) produced by methods of severe plastic deformation and accordingly this report focuses on very recent developments demonstrating the potential of using BNM for advanced and functional applications in engineering and medicine.  相似文献   
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The effluent stream from the industrial production of the herbicide trifluraline (amination water) was submitted to a combined treatment of a physical-chemical process (coagulation) with an advanced oxidation process (Fenton). The recovering of the residual sludge was performed. The combined coagulation-Fenton-sedimentation process proved to be very suitable for wastewater color reduction (91.6%), promoting considerable abatement of the organic load (63.4% COD reduction). According to the fractionary factorial design, the main effects of pH (A) and Fenton sludge (B) variables were considered statistical fluctuations of the process (and not decisive), while the main effects of Fe(3+) (C), Fe(2+) (D) and H(2)O(2) (E), as well as the interactions between variables A and B, A and E, C and D and C and E were considered significant. The obtained results suggest that the combined process can be advantageous for the treatment of recalcitrant industrial effluents, such as the amination water from the trifluraline production.  相似文献   
108.
A novel flying-optical-head data storage technology is described. It is based on a micro-optical recording head that contains a silicon micromachined torsional mirror for high-bandwidth track following. Multiple heads and disks are contained in a Winchester-style rotating disk drive. Single-mode optical fibers provide light delivery to and from the heads. Both polarization-maintaining and low-birefringence fiber systems have been implemented for magneto-optical (MO) recording. A fixed optics module containing a laser diode, MO detection optics, and a 1 x N fiber bundle switch has been developed as an integral part of this new recording architecture. A 5.25-in. (13.33-cm), half-height prototype drive design and its performance are presented.  相似文献   
109.
The accumulation of five murine single-chain variable fragments, binding to dihydroflavonol 4-reductase, was analyzed in transgenic Petunia hybrida plants. The five scFv-encoding sequences were cloned in an optimized plant transformation vector for expression in the cytosol under control of the 35S promoter. In a transient expression assay we found that the scFv expression levels were reproducible and correlated with those in stably transformed petunia. Our results show that accumulation in the cytosol strongly depends on the intrinsic properties of the scFv fragment. Three of the five scFv fragments accumulated to unexpectedly high levels in the cytosol of the primary transformants, but no phenotypic effect could be detected. Experimental results indicate that one of the scFv fragments accumulated in the cytosol to 1% of the total soluble protein as a functional antigen-binding protein in the absence of disulphide bonds. This observation supports the idea that certain antibody fragments do not need disulphide bonds to be stable and functional. Such scFv scaffolds provide new opportunities to design scFv fragments for immunomodulation in the cytosol.  相似文献   
110.
This paper introduces “swiveled Rényi entropies” as an alternative to the Rényi entropic quantities put forward in Berta et al. (Phys Rev A 91(2):022333, 2015). What distinguishes the swiveled Rényi entropies from the prior proposal of Berta et al. is that there is an extra degree of freedom: an optimization over unitary rotations with respect to particular fixed bases (swivels). A consequence of this extra degree of freedom is that the swiveled Rényi entropies are ordered, which is an important property of the Rényi family of entropies. The swiveled Rényi entropies are, however, generally discontinuous at \(\alpha =1\) and do not converge to the von Neumann entropy-based measures in the limit as \(\alpha \rightarrow 1\), instead bounding them from above and below. Particular variants reduce to known Rényi entropies, such as the Rényi relative entropy or the sandwiched Rényi relative entropy, but also lead to ordered Rényi conditional mutual information and ordered Rényi generalizations of a relative entropy difference. Refinements of entropy inequalities such as monotonicity of quantum relative entropy and strong subadditivity follow as a consequence of the aforementioned properties of the swiveled Rényi entropies. Due to the lack of convergence at \(\alpha =1\), it is unclear whether the swiveled Rényi entropies would be useful in one-shot information theory, so that the present contribution represents partial progress toward this goal.  相似文献   
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