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Clinical and epidemiological evidence indicate a relationship between thyroid diseases and melanoma. In particular, the hypothyroidism condition appears to promote melanoma spread, which suggests a protective role of thyroid hormones against disease progression. In addition, experimental data suggest that, in addition to thyroid hormones, other hormonal players of the hypothalamic–pituitary–thyroid (HPT) axis, namely the thyrotropin releasing hormone and the thyrotropin, are likely to affect melanoma cells behavior. This information warrants further clinical and experimental studies in order to build a precise pattern of action of the HPT hormones on melanoma cells. An improved knowledge of the involved molecular mechanism(s) could lead to a better and possibly personalized clinical management of these patients.  相似文献   
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In the context of monitoring water quality in natural ecosystems in real time, on-line data quality control is a very important issue for effective system surveillance and for optimizing maintenance of the monitoring network. This paper presents some applications of recursive state-parameter estimation algorithms to real-time detection of signal drift in high-frequency observations. Two continuous-discrete recursive estimation schemes, namely the Extended Kalman Filter and the Recursive Prediction Error algorithm, were applied to assuring the quality of the dissolved oxygen (DO) time series, as obtained from the Lagoon of Venice (Italy) during August 2002, through the real-time monitoring network of the Magistrato alle Acque (the Venice Water Authority). Results demonstrate the effectiveness of the methodology in early detection of a probable drift in the DO signal. Comparison of these results with those obtained from the application of a related recursive scheme (a Dynamic Linear Regression procedure) suggests the strong benefits of approaching the problem of on-line data quality control with several (not merely a single) independent such estimation methods.  相似文献   
165.
Client requirements for real-time communication services   总被引:3,自引:0,他引:3  
A set of performance specifications that seem appropriate for real-time computer communication services is proposed. They include various types of delay bounds, throughput bounds, and reliability bounds. Other requirements and desirable properties are described from a client's viewpoint, and the ways in which each requirement is to be translated to make it suitable for lower levels in the protocol hierarchy are examined. Some examples of requirements specification are presented, and possible objections to the approach are discussed  相似文献   
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This paper presents a high-stability, single-phase hybrid polyelectrolyte (SPHP) applied in a large EC device (5×10 cm2) using WO3 (electrochromic) and CeO2–TiO2 (counter-electrode–ion storage) electrodes, both produced by Leibniz—Institut of New Materials (Leibniz—INM, Germany). The electrochromic device exhibited excellent color and bleach reversibility, high coloration efficiency (>35 cm2/C) from the first cycle up to more than 60,000 CA cycles, and a maximum constant rate of deintercalation/intercalation (Oout/Qin=1). Its remarkable behavior and high stability render this material an excellent candidate for application in electrochromic devices.  相似文献   
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In this article, four linearizing techniques are compared with each other when they are used in a common-emitter SiGe HBT LNA. Finally, when all of them are employed together, improved linearity of the LNA is observed and more than 10 dBm of IIP3 and −5 dBm of 1-dB gain input compression point are realized when the circuit is fed with 2.4 V. © 2004 Wiley Periodicals, Inc. Int J RF and Microwave CAE 14, 144–152, 2004.  相似文献   
170.
Microgravity offers ideal diffusive conditions for the investigation of the dynamic processes involving surfactant adsorption. Here a summary of the results obtained during the FAST (Facility for Adsorption and Surface Tension studies) experiments on board the NASA Shuttle STS-107 is given. The measured data pertinent to interfacial rheology — i.e., the response of dynamic interfacial/surface tension to imposed perturbation of the interfacial area — for water-hexane and water-air interfaces, in the presence of different non-ionic surfactants are reported and utilised to test available models and to check fundamental aspects of the modelling of dilational rheology.  相似文献   
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