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71.
As a popular method for longwearing lipsticks, self-organizing polymers [e.g. glyceryl ether modified dimethicone (GE)], which can form a gel with a small amount of water are used. However, these polymers have the defect that they tend to inhibit the dispersibility of pigments, especially in a lipstick containing a large amount of liquid isoparaffin that has high moisturizing properties. In this study, the compatibility of the longwearing property and the high dispersibility of pigments in isoparaffin-rich lipstick has been investigated. The introduction of alkyl chain moieties to the GE structure markedly improved the pigment dispersibility. However, random copolymerization type structure inhibited the longwearing properties. On the other hand, the introduction of an alkyl chain to the both ends of GE did not affect the longwearing properties. For further improvement of the pigment dispersibility, fine silica particles were investigated as a dispersant. The compatibility of longwearing properties and good dispersibility of pigments was achieved with silica particles. TEM observation and 1H-NMR measurement revealed that GE was absorbed on silica particles and the silica formed a network in the lipstick composition. We assume that this organic-inorganic hybrid aggregate has no adverse effect on the properties of pigments in the lipstick, hence no flocculation of pigments occurs.
Keywords:  longwearing lipstick, polymer, pigment, dispersibility, fine particle silica, glyceryl ether modified dimethicone, moisturizing properties, organic-inorganic hybrid aggregate, alkyl chain  相似文献   
72.
Conventional sunscreen products generally must strike a compromise between efficacy and product feel; the hydrophobic ingredients that provide the sun protection generally impart an unpleasant, greasy feel and the greater the SPF rating, the worse the greasy feel. We tested an idea that a water-based sunscreen gel formulation containing inorganic UV absorbers would provide an effective way to address these problems. Our goal was to find a way to disperse inorganic sunscreen materials in water and to incorporate them into a water-based gel which would provide a more pleasant product feel. After extensive research we discovered a polymer-zinc oxide composite (P-ZnO) with high UV protective effect and high dispersibility in water. In dried powdered form, P-ZnO can be easily dispersed in water. P-ZnO makes it possible to formulate a gel-type sunscreen, which is not possible using commercially available inorganic powders. The composite size of P-ZnO is about 500 nm and its structure consists of a dense aggregate of nano-ZnO having a size distribution in the 5–10 nm range and amorphous layers of poly acrylic acid coating zinc oxide to control the particle growth, block surface activity and prevent aggregation. The water-based P-ZnO sunscreen gel offers UV protection comparable to conventional products in a delivery vehicle that is much more pleasant to use.  相似文献   
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The force feedback algorithm is presented for the manipulator which consists of a high stiffness position servo system with six-degree of freedom and has a compliant six-component force sensor at its wrist. The obtained algorithm has the following three features. First, this algorithm gives the relation between the position and orientation of the wrist at the present step and that of the wrist to be attained at the next step. Second, an efficient calculation method to obtain each joint movement satisfying this relation is proposed. Third, this algorithm reduces the force feedback control to the position feedback control of each joint in case the force sensor is sufficiently compliant compared with its environment.  相似文献   
75.
Medical audit and continuing medical education (CME) are now the mainstays of quality assurance in hospitals. Audits should address problems that have serious consequences for patients if proper treatment is not given. The single most important step is the selection of essential or scientific criteria that relate process to outcomes. CME does less than commonly believed to improve care. Today, quality assurance increasingly means a near-guarantee to every patient of appropriate treatment and fewest possible complications. Maintenance of the public trust rests on a firm commitment of the medical staff and board to this principle, implemented through an organized program of quality assurance. Under these conditions, medical audit and CME can effectively improve care by improving physician performance.  相似文献   
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Studies of lymphocyte turnover in animal models have implications for understanding the mechanism of cell killing and the extent of lymphocyte regeneration in human immunodeficiency virus infection. Quantitative analyses of the sequential changes in bromodeoxyuridine labeling of CD4 and CD8 T lymphocytes not only revealed the normal proliferation and death rates of these cell populations in uninfected macaques, but also showed a substantial increase in these rates associated with simian immunodeficiency virus (SIV) infection. Faster labeling and delabeling in memory and na?ve T lymphocyte subpopulations as well as in NK (natural killer) and B cells were also observed in infected macaques, suggesting a state of generalized activation induced by SIV.  相似文献   
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This paper presents the first generalization bounds for time series prediction with a non-stationary mixing stochastic process. We prove Rademacher complexity learning bounds for both average-path generalization with non-stationary \(\beta \)-mixing processes and path-dependent generalization with non-stationary \(\phi \)-mixing processes. Our guarantees are expressed in terms of \(\beta \)- or \(\phi \)-mixing coefficients and a natural measure of discrepancy between training and target distributions. They admit as special cases previous Rademacher complexity bounds for non-i.i.d. stationary distributions, for independent but not identically distributed random variables, or for the i.i.d. case. We show that, using a new sub-sample selection technique we introduce, our bounds can be tightened under the natural assumption of asymptotically stationary stochastic processes. We also prove that fast learning rates can be achieved by extending existing local Rademacher complexity analyses to the non-i.i.d. setting. We conclude the paper by providing generalization bounds for learning with unbounded losses and non-i.i.d. data.  相似文献   
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