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1.
Neurodegenerative diseases represent a set of pathologies characterized by an irreversible and progressive, and a loss of neuronal cells in specific areas of the brain. Oxidative phosphorylation is a source of energy production by which many cells, such as the neuronal cells, meet their energy needs. Dysregulations of oxidative phosphorylation induce oxidative stress, which plays a key role in the onset of neurodegenerative diseases such as Alzheimer’s disease (AD), Parkinson’s disease (PD), and amyotrophic lateral sclerosis (ALS). To date, for most neurodegenerative diseases, there are no resolute treatments, but only interventions capable of alleviating the symptoms or slowing the course of the disease. Therefore, effective neuroprotection strategies are needed. In recent years, natural products, such as curcuminoids, have been intensively explored and studied for their therapeutic potentials in several neurodegenerative diseases. Curcuminoids are, nutraceutical compouns, that owen several therapeutic properties such as anti-oxidant, anti-inflammatory and neuroprotective effects. In this context, the aim of this review was to provide an overview of preclinical and clinical evidence aimed to illustrate the antioxidant effects of curcuminoids in neurodegenerative diseases. Promising results from preclinical studies encourage the use of curcuminoids for neurodegeneration prevention and treatment.  相似文献   
2.
Bulletin of Engineering Geology and the Environment - Salt crystallization is a strong weathering agent in porous building materials. The crystallization pressure exerted by salt crystals, growing...  相似文献   
3.
Environmental pollution arising from industrial implants and urban factors is constantly increasing, causing aesthetical and durability concerns to urban structures exposed to the atmosphere.  相似文献   
4.
In the recent past, many efforts have been carried out in order to evaluate the feasibility of implementing closed-loop controlled neuroprostheses based on the processing of sensory electroneurographic (ENG) signals. The success of these techniques mostly relies on the development of processing algorithms capable of extracting the necessary kinematic information from these signals. Soft-computing algorithms can be very useful when dealing with the complexity of the neuromuscular system because of their generalization ability and model-free structure. In this paper, these techniques were used to extract angular position information from the ENG signals recorded from muscle afferents in animal model using cuff electrodes. Specifically, a genetic algorithm-based dynamic nonsingleton fuzzy logic system (named GA-DNSFLS) was developed and tested on different types of angular trajectories (characterized by small or large angular excursions). In particular, two different Takagi-Sugeno-Kang (TSK)-like structures were used in the consequent part of the neuro-fuzzy model in order to verify which one could improve the generalization abilities (intrasubject and intersubject). The results showed that the GA-DNSFLS was able to reconstruct the trajectories giving interesting results in terms of correlation between the actual and the predicted trajectories for small excursion movements during intrasubject and intersubject tests. Particularly, one of the TSK models showed better results in terms of intersubject generalization. The simulations conducted with the large excursion movements led in some cases to interesting results but further experiments are necessary in order to analyze this point more in deep.  相似文献   
5.
Networks of N identical catalytic reactors with periodically switched inlet and outlet sections are studied for first‐order irreversible exothermic reactions. Switching strategies with inlet and outlet sections periodically jumping a fixed number ns of reactors are considered and the mechanisms governing the formation of traveling temperature wave‐trains are analyzed as ns and N are varied. To this aim, a geometric approach to the analysis of the network energy balance is developed. Based on this approach, infinite domains of traveling temperature wave‐trains are predicted for any ns and N. Analytical approximations are derived for the stability limits and the spatiotemporal patterns of these regimes. Stability boundaries predicted analytically include for any solution the largest part of the stability region computed by numerical simulation. Moreover, good agreement is found between the structure of the spatiotemporal patterns computed numerically and that predicted based on the proposed approach. © 2011 American Institute of Chemical Engineers AIChE J, 2012  相似文献   
6.
Perhydrotriphenylene‐based channel‐forming inclusion compounds (ICs) and thin films made of polyphenylenevinylene (PPV)‐type oligomers with terminal alkoxy groups are investigated and compared in a combined experimental and theoretical approach. Interchromophore interactions and host‐guest interactions are elucidated by UV/Vis and Raman spectroscopy. The impact of the local environment of the chromophore on the optical and photophysical properties is discussed in light of quantum‐chemical calculations. In stark contrast to thin films where preferential side‐by‐side orientation leads to quenching of photoluminescence (PL) via non‐emissive traps, the ICs are found to be attractive materials for opto‐electronic applications: they offer high chromophore concentrations, but at the same time behave as quasi‐isolated entities of tightly packed, well‐oriented objects with high PL quantum yields and the possibility of color tuning.  相似文献   
7.
Thin film p-ZnCuTe semiconductors were synthesized by electrodeposition. The deposition mechanism was investigated by cyclic voltammetry; formation of the ternary compound, having the cubic structure of ZnTe, was obtained upon annealing at 400°C, as confirmed by X-ray diffraction. A direct energy gap of 1.7 eV was determined by optical absorption experiments. Measurements of the Hall effect and Van der Pauw conductivity showed an increase of carrier concentration and a decrease of sheet resistance for ZnCuTe with respect to zinc telluride.  相似文献   
8.
9.
In continuous Friend leukemia cell exposure to tTAuP, the IC50 was 0.2 microM whereas in cells exposed 15 or 60 min to tTAuP followed by 72 h in drug-free medium the IC50 was 2.2 and 1.3 microM respectively. A combination of tTAuP and cisplatin (CDDP) is shown to be more active than either agent alone. Intracellular accumulation studies analysed by SXRF have shown that to achieve a cytotoxic effect, large concentrations of gold are necessary to accumulate in both the nuclear and cytoplasmic fraction. However, at cytostatic doses (1 microM), tTAuP has no effect on the cell cycle but does affect DNA synthesis. At a higher dose, greater than that necessary to induce cytotoxicity, it produces DNA damage, as observed by alkaline elution method. When cells were exposed to toxic doses of tTAuP (10 microM) in the presence of albumin, cytotoxicity was significantly reduced. Similar results were obtained when cells were co-treated with L-cysteine, dithiothreitol or reduced gluthatione. Reduced cytotoxic effect can be related to the interaction with free thiol groups. According to these data it is concluded that tTAuP is highly effective in vitro; whether it is active in vivo remains to be determined.  相似文献   
10.
本文介绍了Power Integrations公司推出的新款控制器IC LinkSwitch-Ⅱ,可以使手机充电器的元件数减少30%,并将空载功耗降低至仅为30mW.  相似文献   
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