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941.
Background: Skinboosters represent the latest category of hyaluronan (HA) hydrogels released for aesthetic purposes. Different from originally developed gels, they are intended for more superficial injections, claiming a skin rejuvenation effect through hydration and possibly prompting biochemical effects in place of the conventional volumetric action. Here, three commercial skinboosters were characterized to unravel the scientific basis for such indication and to compare their performances. Methods: Gels were evaluated for water-soluble/insoluble-HA composition, rheology, hydration, cohesivity, stability and effect, in vitro, on human dermal fibroblasts towards the production of extracellular matrix components. Results: Marked differences in the insoluble-hydrogel amount and in the hydrodynamic parameters for water-soluble-HA chains were evidenced among the gels. Hydration, rigidity and cohesivity also varied over a wide range. Sensitivity to hyaluronidases and Reactive Oxygen Species was demonstrated allowing a stability ranking. Slight differences were found in gels’ ability to prompt elastin expression and in ColIV/ColI ratio. Conclusions. A wide panel of biophysical and biochemical parameters for skinboosters was provided, supporting clinicians in the conscious tuning of their use. Data revealed great variability in gels’ behavior notwithstanding the same clinical indication and unexpected similarities to the volumetric formulations. Data may be useful to improve customization of gel design toward specific uses.  相似文献   
942.

The 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 ceramic films were prepared using the water-based tape casting method. Two main components of the slurry are water and solids. The concentrations of other chemicals, the surfactant and binder, are at the level of 1 wt.%. Both binder and surfactant are eco-friendly polymers. Additional chemicals are not required. The optimal concentration of surfactant determined through viscosity measurements. The density of the ceramics was studied as a function of the concentration of water and binder. The density is nearly independent of amount of water despite a wide range of values of concentration. This independence is a powerful tool to cast using different techniques. The density substantially depends only on binder concentration. The polymers removal protocol of the cast films was optimized using thermogravimetric analysis. As a result, the translucent ceramic films with a relative density of 98% and thickness of 70 μm were prepared. The permittivity, remnant polarization and pyrocurrent measurements, along with the scanning electron microscopy, prove the high density of the ceramics.

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943.
944.

This work presents an application of bio-inspired flower pollination algorithm (FPA) for tuning proportional–integral–derivative (PID) controller in load frequency control (LFC) of multi-area interconnected power system. The investigated power system comprises of three equal thermal power systems with appropriate PID controller. The controller gain [proportional gain (K p), integral gain (K i) and derivative gain (K d)] values are tuned by using the FPA algorithm with one percent step load perturbation in area 1 (1 % SLP). The integral square error (ISE) is considered the objective function for the FPA. The supremacy performance of proposed algorithm for optimized PID controller is proved by comparing the results with genetic algorithm (GA) and particle swarm optimization (PSO)-based PID controller under the same investigated power system. In addition, the controller robustness is studied by considering appropriate generate rate constraint with nonlinearity in all areas. The result cumulative performance comparisons established that FPA-PID controller exhibit better performance compared to performances of GA-PID and PSO-PID controller-based power system with and without nonlinearity effect.

  相似文献   
945.
The purpose of this paper is to propose a new method for the optimization of the output transition in the case of set‐point reset for LTI, non‐minimum phase, possibly non‐hyperbolic plants. Assuming that the plant is stabilized by a proper feedback controller, the problem consists in finding a feedforward linear filter yielding a suitable reference trajectory for the closed‐loop system. The approach situates in the framework of model pseudo‐inversion because the external reference trajectory is computed starting from some desired features of the transient output between the two set points. A significant aspect of the new method is that the transition trajectory is not ‘ad hoc’ exactly prespecified by the designer. Rather, it is implicitly defined by the procedure for the minimization of a suitable multi‐objective quadratic cost functional. As no pre‐actuation is required, the method can be practically implemented on line and also works for the critical class of non‐hyperbolic systems. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
946.
Purpose: The aim of the present work was to set up an optimized protocol for human cerebrospinal fluid amyloid‐β (Aβ) profiling. Experimental design : We devised an immunoproteomic assay that employs monoclonal antibodies (mAbs) on Preactivated Surface (PS20) chip array followed by SELDI TOF MS. A comparison of a number of factors was performed, and the impact of these differences was noted. Each variable was tested using in parallel two different mAbs, 6E10 and 4G8. In addition, we tested whether the combined use of these two mAbs could improve the capture of N and C‐terminally truncated Aβ peptides and then the quality of spectra. Results : The best results were obtained using a mixture of Aβ mAbs (0.125μg/μL 6E10+4G8): 15 Aβ peptides (including 3 N‐terminally truncated forms) were detected. Conclusions and clinical relevance : This approach has many potential advantages in speed, sensitivity and economy of reagents and could be helpful in order to define the role played by specific Aβ truncated forms in cognitive decline.  相似文献   
947.
Neural Computing and Applications - The paper proposes an approach to the design of the chemical composition of steel, which is based on neural networks and genetic algorithms and aims at achieving...  相似文献   
948.
Multimedia Tools and Applications - Recent research on biometrics focuses on achieving a high success rate of authentication and addressing the concern of various spoofing attacks. Although hand...  相似文献   
949.
The research developed from the identification of the most highly cited Soviet journals in the physical and life sciences. Several measures of growth and citedness were taken at the beginning and end of a recent five-year period, 1982–87, in order to generally assess the functions of these journals. The research involved making comparisons among these groupings of journals and control groupings of journals with similar content, but not published in the Soviet Union. Differences in citedness could be related, in the physical sciences, to the scale of Russophone science within world sciences, but not in the life sciences. In the physical sciences, there are increases in the citedness across Soviet and Western journals; but in the Soviet journals the increase is several times greater than in the control grouping. In sharp contrast, the largest, most cited, Western life sciences' journals have increased in citedness and other groupings, including Soviet journals, have declined. The measures on control groups show that the extreme levels of improvement in citedness on the part of Soviet physical sciences' journals reflect local, i.e. Soviet, developments. The decrease in citedness of Soviet life sciences' journals seems, instead, tied broadly to events in the world life sciences' literature. There has been, apparently a centralizing of attention within those discipline on those few journals publishing major findings while leaving the rest of the world literature behind. In addition, the research developed several findings on the formal properties of the measures used.  相似文献   
950.
Chromium carbide modified C/C and Ti6Al4V were successfully joined using a TiCuZrNi brazing alloy in powder form. The braze/composite interface and the mechanical strength of C/C‐Ti6Al4V joints were evaluated. The apparent shear strength of chromium carbide modified C/C joined to Ti6Al4V, measured by single lap test in compression, was 52 ± 6 MPa, which was highest among that without chromium carbide modification (15 ± 2 MPa) and the intrinsic C/C shear strength. The fractography of joints without chromium carbide modification indicated that failure mainly occurred at the TiC layer formed at the composite/braze interface while the joints with chromium carbide modification failed within the C/C.  相似文献   
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