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101.
Accumulative evidence suggests that the implementation of international standard operating procedures, induce, by their virtues, major organizational changes. These changes are both cultural and behavioral including changes in decision-making processes, organizational norms, and values. The decision of any organization to adopt quality assurance, specifically via accreditation, should be regarded as a strategic one. As such, it prerequisites top management commitment, budgeting the process and promoting active inter-collaboration of all organizational members. The accreditation process according to ISO/IEC 17025:1999 of the Haifa Public Health Laboratory, will be used as a case study. A number of practical benefits of such organizational changes will be demonstrated and discussed, among them improved quality customer service and handling customer's complaints, establishing multichannel communication, enhanced interlaboratory collaboration and coordination. It is important to note that the accreditation process was accompaniment by extensive training of both management and employees on-site and off-site.  相似文献   
102.
Irradiation of mouse spermatozoa by 630 nm He-Ne laser was found to enhance the intracellular calcium levels and fertilizing potential of these cells. The effect of light on calcium transport and on fertilization rate was abrogated in the absence of Ca2+during the irradiation time, indicating that the effect of light is Ca2+dependent. The stimulatory effect of light on Ca2+uptake was abolished in the presence of a voltage-dependent Ca2+-channel inhibitor nifedipine, indicating the involvement of a plasma membrane voltage-dependent Ca2+channel. Furthermore, the stimulatory effect of light was completely inhibited by the mitochondrial uncoupler FCCP, indicating that laser irradiation might affect the mitochondrial Ca2+transport mechanisms. A causal association between laser irradiation, reactive oxygen species (ROS) generation and sperm function was indicated by studies with ROS scavengers, superoxide dismutase (SOD) and catalase, and exogenous hydrogen peroxide. The SOD treatment, which enhanced H2O2 production, resulted in increased Ca2+uptake and enhanced fertilization rate. On the other hand, catalase, which decomposes H2O2, impaired the light-induced stimulation in Ca2+uptake and the fertilization rate. Taken together, the data suggest that H2O2 might be involved in the irradiation effects, and indeed laser irradiation enhances the production of H2O2, by spermatozoa. These results indicate that the effect of 630 nm He-Ne laser irradiation is mediated through the generation of H2O2 by the spermatozoa and that this effect plays a significant role in the augmentation of the sperm cells' capability to fertilize metaphase H-arrested eggs in vitro.  相似文献   
103.
Time-resolved electron paramagnetic resonance (TREPR) spectroscopy was used to study two functionalized fullerenes consisting of a C60 moiety covalently linked to TEMPO radical via spacers of different length. Photoinduced electron spin polarization (ESP) reflecting a non-Boltzmann population within the energy levels of the spin system was observed in the electronic ground and excited states. Both fullerenes are characterized by a sign inversion of their TREPR spectra. A new mechanism of ESP generation was suggested to explain the experimental results. This mechanism, termed as the reversed quartet mechanism (RQM), includes the intersystem crossing process, which generates ESP in the excited trip-doublet and trip-quartet (2T1 and 4T1) states. This ISC is accompanied by ESP transfer to the ground state (2S0) by either electron-transfer reaction (in our case via charge transfer state, 2CT, i.e., 2T1--> 2CT --> 2S0 or internal conversion, 2T1--> 2S0.  相似文献   
104.
It is shown that in every n-colouring ((n ? 1)-colouring) of a projective plane (affine plane) of odd order n at least one line has three points of the same colour.  相似文献   
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We establish a new estimate for the topological degree of continuous maps from the sphere SN into itself, which answers a question raised in Bourgain, Brezis, and Mironescu [Commun. Pure Appl. Math. 58 (2005) 529–551] and extends some of the results proved there, as well as in recent work by these authors (Lifting, degree, and distributional Jacobian revisited, http://ann.jussieu.fr/publications). To cite this article: J. Bourgain et al., C. R. Acad. Sci. Paris, Ser. I 340 (2005).  相似文献   
108.
The effect of hydrodynamic interaction on the separation dependence of the center of mass and relative pair diffusion coefficients of colloid particles in a quasi-one-dimensional system, including the influence of proximate walls, is calculated using the method of reflections. There is excellent agreement between the theoretical predictions and the experimental data. We show that the separation dependence of the relative pair diffusion coefficient has an oscillatory structure on the scale length of the correlation length in the system, and we directly relate that oscillatory structure to the pair correlation function of the system.  相似文献   
109.
In multi-period insurance contracts (such as automobile insurance contracts), unlike single-period ones, the premiums that the insured must pay increase whenever he files a claim. Hence, the buyer faces a problem that is absent in one-period models, namely: he must determine for which damages he should file a claim and for which he should not.The optimal claims policy of the buyer is presented for a large class of insurance contracts. It is shown that the buyer will file a claim only if it is larger than some critical value. Based on this it is shown that the buyer prefers a contract that provides full coverage above a deductible for damages that exceed his critical value. In this case the optimal contract is not unique since the buyer is indifferent to the form of the contract for damages below his critical value. It is shown, however, that as in one-period models (Arrow (1963, 1974)) there exists an optimal contract that provides full coverage above a deductible. In multi-period setting, however, the buyer will file a claim only if the damage is sufficiently higher than the deductible.It is also shown that the buyer prefers a strictly positive deductible. Unlike the one-period case (Mossin (1968)), this result holds true even if the premium rates equal the expected payments.  相似文献   
110.
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