The postprandial inflammatory response after ingestion of heated oils in obese persons is reduced by the presence of phenol compounds

Scope Heating during the process of cooking alters the chemical properties of foods and may affect subsequent postprandial inflammation. We tested the effects of four meals rich in different oils subjected to heating on the postprandial inflammatory metabolism of peripheral blood mononuclear cells (PBMCs). Methods and results Twenty obese participants received four breakfasts following a randomized crossover design, consisting of milk and muffins made with different oils (virgin olive oil (VOO), sunflower oil (SFO), and a mixture of seeds oil (SFO/canola oil) with added either dimethylpolysiloxane (SOD), or natural antioxidants from olive mill wastewater alperujo (phenols; SOP)), previously subjected to 20 heating cycles. Postprandial inflammatory status in PBMCs was assessed by the activation of nuclear NF‐κB, the concentration in cytoplasm of the NF‐κB inhibitor (IκB‐α), the mRNA levels of NF‐κB subunits and activators (p65, IKKβ, and IKKα) and other inflammatory molecules (TNF‐α, IL‐1β, IL‐6, MIF, and JNK), and lipopolysaccharide (LPS) levels. VOO and SOP breakfasts reduced NF‐κB activation, increased IκB‐α, and decreased LPS plasma concentration. SFO increased IKKα, IKKβ, p65, IL‐1b, IL‐6, MIF, and JNK mRNA levels, and plasma LPS Conclusion Oils rich in phenols, whether natural (VOO) or artificially added (SOP), reduce postprandial inflammation, compared with seed oil (sunflower).     

The antioxidants in oils heated at frying temperature,whether natural or added,could protect against postprandial oxidative stress in obese people

We have investigated the effects of the intake of oils heated at frying temperature in order to find an oil model for deep-frying that prevents postprandial oxidative stress. Twenty obese people received four breakfasts following a randomised crossover design consisting of different oils (virgin olive oil (VOO), sunflower oil (SFO), and a mixed seed oil (SFO/canola oil) with added dimethylpolysiloxane (SOX) or natural antioxidants from olives (SOP)), which were subjected to 20 heating cycles. The intake of SFO-breakfast reduced plasma GSH levels and the GSH/GSSG ratio, increased protein carbonyl levels, and induced a higher gene expression of the different NADPH-oxidase subunits, Nrf2-Keap1 activation, gene expression of the antioxidant enzymes in peripheral blood mononuclear cells and antioxidant plasma activities than the intake of the breakfasts prepared with VOO, SOP and SOX. Oils with phenolic compounds, whether natural (VOO) or artificially added (SOP), or with artificial antioxidant (SOX), could reduce postprandial oxidative stress compared with sunflower oil.     

Stability comparison of two quadruple-wavelength switchable erbium-doped fiber lasers

An experimental stability comparison between two different switchable Erbium-doped fiber lasers (EDFL) is carried out. Both topologies use fiber Bragg grating reflectors in order to select the emission wavelengths and two 2 × 4 optical switches. By adjusting the switches combinations, the lasers can be switched among the sixteen different wavelength lasing configurations. An output power and wavelength instability analysis with time for both topologies was performed. The experimental results confirm that the topology based on a serial configuration offers a better stability, efficiency and higher optical signal-to-noise ratios (OSNR) than the one based on a parallel configuration.     

Optimization of the frequency-modulated continuous wave technique for referencing and multiplexing intensity-based fiber optic sensors

In this paper, we demonstrate the interrogation of fiber optic intensity sensors by using the combination of the frequency-modulated continuous wave concept with the spectral selective reflectivity of fiber Bragg gratings. Thus, we multiplex these kinds of sensors with this technique having simultaneously a referenced system. The basis of this dual functionality is described and results are presented for the case of interrogation of two multiplexed intensity sensors. Their evaluation permits to establish the conditions to address a sensor network of this type. Also, it is proposed a strategy to implement this sensing approach without the requirement of using optical fiber delay lines in the sensor heads.     

Frequency Modulated Continuous Wave System for Optical Fiber Intensity Sensors With Optical Amplification

We report on the use of erbium doped fiber (EDF) amplification to enhance a frequency modulated continuous wave (FMCW) technique for referencing optical intensity sensors located between two Bragg grating structures. The experiment combines the concept of FMCW with the spectrally selective mirror properties of Bragg gratings to interrogate with referencing properties intensity based sensors. The interrogation system without amplification yields a sensor resolution of around 0.078 dB. When the EDF amplifier is introduced into the experimental set up, the sensor sensitivity does not change, but the signal-to-noise ratio is improved, resulting into an enhanced resolution of 0.025 dB. We also obtain a remote sensing operation at a location of 50 km, showing the feasibility of this configuration to be used as a remote sensing application.