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Purpose : In the last few years, serum and joint synovial fluid have been extensively analyzed for the proteomic research of rheumatoid arthritis (RA) biomarkers. Nonetheless, to date, there have been no studies investigating salivary biomarkers in this condition. Therefore, aim of this study is to investigate the presence of potential biomarkers of RA in human whole saliva. Experimental design : We combined 2‐DE and MS to analyze the whole saliva protein profile of 20 RA patients in comparison with 20 sex‐ and age‐matched healthy subjects. Results : Eight salivary proteins resulted differentially expressed, namely calgranulin A, calgranulin B, apolipoprotein A‐1, 6‐phosphogluconate dehydrogenase, peroxiredoxin 5, epidermal fatty acid‐binding protein, 78 kDa glucose‐regulated protein precursor (GRP78/BiP), and 14‐3‐3 proteins. It is particularly interesting that chaperone GRP78/BiP showed the greatest increase in RA patients. This finding was validated by Western Blot analysis and the over‐expression of GRP78/BiP appear to be distinctive of RA and drugs treatment independent. Conclusions and clinical relevance : This study provides a rationale for further studies aimed at evaluating any correlation between GRP78/BiP and different clinical/serological aspects of the disease in order to improve the diagnostic algorithms of RA.  相似文献   
703.
The analysis of the impact of video content and transmission impairments on Quality of Experience (QoE) is a relevant topic for the robust design and adaptation of multimedia infrastructures, services, and applications. The goal of this paper is to study the impact of video content on QoE for different levels of impairments. In more details, this contribution aims at i) the study of the impact of delay, jitter, packet loss, and bandwidth on QoE, ii) the analysis of the impact of video content on QoE, and iii) the evaluation of the relationship between content related parameters (spatial-temporal perceptual information, motion, and data rate) and the QoE for different levels of impairments.  相似文献   
704.
Equations are derived for the electric potentials [electroencephalogram (EEG)] produced by dipolar sources in a multiregion bicentric-spheres volume-conductor head model. Being the equations valid for an arbitrary number of regions, our proposal is a generalization of many spherical models presented so far in literature, each of those regarded as a particular case of our multiregion model. Moreover, our approach allows considering new features of the head volume-conductor to better approximate electrical properties of the real head.  相似文献   
705.
A new and practical way to introduce an alkyl fragment in the β‐position of aliphatic carboxylic acid derivatives with high enantioselectivities by the use of a commercially available chiral ligand is reported. N‐Acylpyrrolidinones, as simple derivatives of an α,β‐unsaturated carboxylic acid, were found to be the substrates of choice featuring good reactivity and high enantioselectivities (up to >99% ee).  相似文献   
706.
A tetrairon(III) single‐molecule magnet is deposited using a thermal evaporation technique in high vacuum. The chemical integrity is demonstrated by time‐of‐flight secondary ion mass spectrometry on a film deposited on Al foil, while superconducting quantum interference device magnetometry and alternating current susceptometry of a film deposited on a kapton substrate show magnetic properties identical to the pristine powder. High‐frequency electron paramagnetic resonance spectra confirm the characteristic behavior for a system with S = 5 and a large Ising‐type magnetic anisotropy. All these results indicate that the molecules are not damaged during the deposition procedure keeping intact the single‐molecule magnet behavior.  相似文献   
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This paper investigates the shape memory capabilities of semicrystalline networks, focusing the attention on poly(ε-caprolactone) (PCL) systems, a class of materials that allows to satisfy important requirements for their applications as biomedical devices, such as the good biocompatibility, the fast recovery of large “temporary” shape configurations, and the easy tailoring of the transformation temperatures. The materials were prepared with various crosslink densities and crosslinking methodologies; in particular, beside a thermal crosslinking based on reactive methacrylic end groups, a novel type of covalently crosslinked semicrystalline systems was prepared by a sol-gel approach from alkoxysilane-terminated PCL precursors, so as to avoid potentially toxic additives typically used for free-radical thermal curing. The materials were subjected to biological tests, to study their ability in sustaining cell adhesion and proliferation, and to thermal characterizations, to evaluate the possibility to tailor their melting and crystallization temperatures. The one-way shape memory (i.e., the possibility to set the material in a given configuration and to recover its pristine shape) and the two-way shape memory response (i.e., the triggered change between two distinguished shapes on the application of an on-off stimulus) were studied by applying optimized thermo-mechanical cyclic histories. The ability to fix the applied shape and to recover the original one on the application of heating (i.e., the one-way effect) was evaluated on tensile bars; further, to investigate a potential application as self-expandable stents, isothermal shape memory experiments were carried out also on tubular specimens, previously folded in a temporary compact configuration. The two-way response was studied through the application of a constant load and of a heating/cooling cycle from above melting to below the crystallization temperature, leading to a reversible elongation/contraction effect, involving maximum strain changes up to about 80%, whose extent may be controlled through the crosslink density.  相似文献   
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The production of electricity from renewable sources plays a strategic role in the future of energy because it helps to effectively manage climate change through an energy generation portfolio with lower emissions of greenhouse gases.Photovoltaic solar energy is safe and sustainable and is characterised by a growing trend with a cumulative installed capacity that has reached a total of 40 GW in 2010.In this paper, investigations are presented using multiple calculations: Energy Payback Time (EPBT), Greenhouse Gas per kilowatt hour (GHG/kWh), Energy Return on Investment (EROI), Greenhouse Gas Payback Time (GPBT) and Greenhouse Gas Return on Investment (GROI). These metrics make it possible to define the energy and environmental performances for a building-integrated photovoltaic system located in Italy.The module efficiency, the embodied energy and the annual solar irradiance are variables that play a strong role in this analysis. The key parameters include the type of solar cells (e.g., mono-crystalline silicon, polycrystalline silicon, amorphous silicon, cadmium telluride) and the location where the system is installed (Milan, Rome and Palermo).The results determine whether solar energy has a viable strategic role in the global energy market.  相似文献   
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