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Sesame oil (SO) is a high-quality and very popular edible oil with pleasant odor and good taste, which has higher economic and nutritional value than other common vegetable oils. However, there is no effective and standardized method for detecting adulterated sesame oil, so there is an urgent need to develop a rapid and effective method for the detection of adulterated sesame oil. In this work, a strategy based on the excitation-emission matrix (EEM) fluorescence spectroscopy combined with multi-way chemometric methods was proposed to distinguish the plant origin of vegetable oils, identify adulterated sesame oil and quantify the level of adulteration of soybean oil (SBO) in SO. Three kinds of multi-way chemometric methods were used in this work. They are alternating trilinear decomposition coupled with partial least squares discriminant analysis (ATLD-PLS-DA), multilinear partial least squares discriminant analysis (N-PLS-DA) and unfolded partial least squares discriminant analysis (U-PLS-DA). The total recognition rates (TRRs) of plant origin of edible oils for the testing set were 79.17%, 100% and 100%, respectively, based on ATLD-PLS-DA, N-PLS-DA and U-PLS-DA model. For the identification of adulterated sesame oil, the TRRs for the testing set were 93.10%, 100% and 100%, respectively. What's more, N-PLS regression and U-PLS regression were used for predicting the adulteration amount of SBO in SO. Satisfactory prediction accuracy with RMSEV = 2.74% was obtained by U-PLS regression. Therefore, it can be concluded that EEM fluorescent fingerprint combined with multi-way chemometric methods is an effective strategy to classify the plant origin of vegetable oils, identify the adulteration of SO and quantify the level of adulteration. [ABSTRACT FROM AUTHOR]

Grade is an important parameter for indicating tea quality, which determines the price of tea. However, it is confusing for consumers to evaluate the grade of teas, as it usually requires skilled experts to make a judgement about its colour, aroma, and taste. Therefore, a strategy that coupled excitation-emission matrix (EEM) fluorescence spectroscopy with three kinds of multi-way classification algorithms was developed for rapid authentication of green tea grade. The first classification model was built using partial least squares discriminant analysis (PLS-DA) based on the resolved relative concentration information provided by parallel factor analysis (PARAFAC). The other two were modeled based on multi-way partial least squares-discriminant analysis (N-PLS-DA) and unfolded partial least squares discriminant analysis (U-PLS-DA), which use full EEM spectral information to establish classification models. Compared with the PARAFAC-PLS-DA model, the N-PLS-DA and U-PLS-DA models provide more accurate and reliable classification results. The total recognition rates of the training set and test set based on N-PLS-DA are 85.1% and 88.8%, respectively. U-PLS-DA model provides 97.8% and 88.8% of total recognition rates for the training set and test set, respectively. Therefore, it can be concluded that full EEM fluorescence spectroscopy combined with multi-way classification methods is a good way to identify the grade of green tea. [ABSTRACT FROM AUTHOR]

In this work, a high-performance liquid chromatography-diode array detection (HPLC-DAD) method combined with chemometrics was developed for differentiating geographical origins of Chinese red wines. Phenolic compounds were firstly detected and quantified by direct injection HPLC-DAD method in thirty red wines originated from two famous wine-growing regions in China. Given the high complexity of the wine samples and the co-elution problems during chromatographic separation, multivariate curve resolution-alternating least squares (MCR-ALS) was utilized to extract pure chromatographic and spectral profiles of each co-eluted compound. Quantification of phenolic compounds was thus achieved even in the presence of overlapping peaks and uncalibrated interferents. The quantitative data of the phenolic compounds in wines provided by the MCR-ALS algorithm were afterwards analyzed by unsupervised principal component analysis (PCA) and hierarchical cluster analysis (HCA) methods and supervised orthogonal partial least squares-discrimination analysis (OPLS-DA) method. Both PCA and HCA results showed that the thirty red wines from different geographical origins could be obviously distinguished, and the OPLS-DA could successfully predict the geographical origins of red wines. This study demonstrated that the HPLC-DAD method combined with chemometrics can be used as an effective tool for differentiating geographical origins of Chinese red wines on the basis of phenolic compounds. [ABSTRACT FROM AUTHOR]

In this paper, an excitation-emission matrix (EEM) fluorescence spectroscopy method coupled with two kinds of multi-way classification algorithms was developed for the identification of the adulteration of Shanxi aged vinegars. The first classification model was built from selective information provided by parallel factor analysis (PARAFAC) based on partial least squares-discriminant analysis (PLS-DA) algorithm and the other one was modeled based on strictly multi-way classification algorithm multi-way partial least squares-discriminant analysis (N-PLS-DA). Both classification models showed good clustering tendency for authentic and adulterated Shanxi aged vinegars. Compared with the PARAFAC-PLS-DA method, more accurate and reliable classification results were provided by the N-PLS-DA method because it is a strictly multi-way classification method and can make the utmost use of the EEM fluorescence information of the vinegar samples. The N-PLS-DA model constructed from the EEM spectra enabled the recognition of adulterated samples with accurate rate of 100% both in training and prediction sets and obtained maximum sensitivity and specificity. This study showed that EEM fluorescence spectroscopy combined with multi-way classification algorithm N-PLS-DA could be used as a good method for the identification of the adulteration of Shanxi aged vinegar samples. [ABSTRACT FROM AUTHOR]

A novel scheme for photonic envelope detection and fiber transmission of 24 GHz impulse radio ultra-wideband (IRUWB) signal is proposed based on phase modulator (PM). In the system, an optics assisted envelope detection unit (OAEDU) is used for filtering one of the first sidebands at the output of PM, then this narrow band optical signal transfers over single-mode fiber (SMF), and the envelope of 24 GHz IR-UWB signal is obtained after photodetection (PD) and low pass filter (LPF). The numerical simulation results show that the combination of PM and OAEDU can alleviate the fiber chromatic dispersion (CD) effectively. The proposed system may provide a simple and cost-effective solution for IR-UWB receiver. [ABSTRACT FROM AUTHOR]

A new receiver is proposed, which uses the fiber optical parametric amplifier (FOPA) in optical code division multiple access (OCDMA) over free space optic (FSO) communication system. The noise tolerance as the performance index in this receiver is derived. The receiver can not only improve the noise tolerance but also change the pump data conveniently for adapting to the length variation of the coding sequence under a complex and fast-changing weather condition. The influence of different factors on the noise tolerance is analyzed, and a significant improvement of about 18.77 dB for the noise tolerance can be achieved when the pump power and the length of coding sequence are 5 W and 256, respectively. [ABSTRACT FROM AUTHOR]

The principle of a novel orthogonal modulation format of differential 8-level phase-shift keying amplitude-shift keying (D8PSK/ASK) with differential bi-phase encoding (DBC) is introduced. Based on it, an optical labeling scheme, in which the payload is 100 Gbit/s D8PSK signal and the label is 10 Gbit/s DBC-ASK signal, is proposed and simulated. The results are compared with other current schemes, and the effects of transmission range, modulation extinction ratio (ER) and received power on system performance are analyzed, respectively. The results show that the spectrum efficiency and bit error rate (BER) are improved greatly, and when the modulation ER is increased to 11 dB, the balanced performance between the payload and label is achieved. [ABSTRACT FROM AUTHOR]

The conversion efficiency and noise figure (NF) of the silicon-on-insulator (SOI) waveguide-based wavelength converter are investigated with the coupled equations. The effects of the pump power, the nonlinear absorption and the waveguide length on the conversion efficiency and noise figure are discussed. The conversion efficiency decreases with the increasing pump power and the noise figure is degraded due to the two-photon absorption (TPA) and the TPA-induced free-carrier absorption (FCA) at the higher pump power. With the increasing of the free carrier lifetime, the conversion efficiency will decrease and the noise figure will increase accordingly. The optimal waveguide length depends on the pump power and the free carrier lifetime. In practical applications, the high conversion efficiency and low noise figure can be achieved by choosing suitable parameters of the silicon waveguide. [ABSTRACT FROM AUTHOR]

Lipid profile (total cholesterol and lipoprotein fractions) has been found to correlate with depression and cognitive impairment across the lifespan. However, the role of lipid levels in self-rated depressive state and cognitive impairment remains unclear. In this study, we examined the relationship between lipid profile (total cholesterol, triglycerides, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol) and cognition in adults with and without self-rated depression. Four hundred and thirty-eight healthy participants completed the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), the Self-Rating Depression Scale (SDS), and a serum lipoprotein test. Using multivariate ANOVA, partial correlation and network analysis, a network linking lipoprotein profile, depressive state and cognition was constructed. A significant difference in serum lipid profile between the high and low depressive groups was detected. Depressive state had a strong negative correlation with cognitive performance. Of the lipid profile, only high-density lipoprotein was positively correlated with depressive symptom severity, whereas the other three indices showed negative correlation with both depressive state and cognitive performance. Our results suggest that serum lipid profile may be directly linked to self-rated depression and cognitive performance. Further studies recruiting larger clinical samples are needed to elucidate the specific effect of lipoprotein on cognitive impairment in mood disorder. [ABSTRACT FROM AUTHOR]

In this paper, a new millimeter-wave (mm-wave) wavelength division multiplexing (WDM) system based on radio-over-fiber (ROF) technology is proposed. In this approach a multi-wavelength light source is obtained by supercontinuum (SC) technique, and mm-wave signals are obtained by using optical heterodyning method. We experimentally demonstrate the generation of optical carriers for 6-WDM channels, obtain 40 GHz mm-wave signals by employing optical heterodyne technique, and successfully achieve low error rate transmission of 2.5 Gbit/s in WDM channels over a distance of 25 km in a G.652 fiber. The experimental results verify that the proposed solution is feasible and cost effective. [ABSTRACT FROM AUTHOR]

Background: Cognitive deficits are common in patients with bipolar disorder (BD). Abnormal high density lipoprotein (HDL) levels have been implicated in cognitive deficits associated with ageing and neurodegenerative disorders. The present study aimed to investigate serum HDL levels, cognitive deficits and their association in patients with BD. Methods: Thirty-seven patients with BD and 37 gender- and age-matched healthy controls (HCs) were recruited in a case–control study. Cognition was assessed using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), and serum HDL levels were measured using enzymatic colourimetry. Results: There was no difference in serum HDL levels between patients with BD and HCs after adjusting for gender, age, education and body mass index (BMI). Cognitive test scores in patients with BD were significantly lower than those in HCs except for the visuospatial/constructional index after adjusting for confounding variables. Serum HDL levels were positively correlated with RBANS total score and language score in patients with BD. Stepwise multiple regression analysis showed that serum HDL levels were significantly correlated with RBANS total score and subscale scores on immediate memory and language in patients with BD after adjusting for confounding factors. Conclusions: Our findings suggest that patients with BD had poorer cognitive performance than HCs except for the visuospatial/constructional domain, and decreased serum HDL levels were correlated with cognitive deficits, especially in immediate memory and language domains in patients with BD. [ABSTRACT FROM AUTHOR]

Cognitive impairment is a core feature of schizophrenia (SCH). In addition to the toxic effect of Bilirubin (BIL), it has antioxidant properties that were associated with the psychopathology and cognitive impairment of psychiatric disorders. The aim of this study was to examine the correlation of serum total BIL (TBIL) concentration with cognitive impairment in SCH patients. We recruited 34 SCH patients and 119 healthy controls (HCs) in this case-control design. Cognition was assessed using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Serum TBIL concentration was measured using the immunoturbidimetric method. Serum TBIL concentration was significantly decreased in SCH patients compared to HCs after adjusting for age, gender, and education. Serum TBIL concentration in SCH patients was also positively correlated with the RBANS immediate memory score. Further stepwise multiple regression analysis confirmed the positive association between serum TBIL concentration and immediate memory score in SCH patients. Our findings supported that the decline in serum TBIL concentration was associated with the immediate memory impairment and psychopathology of SCH. [ABSTRACT FROM AUTHOR]