Controlled synthesis of α-Fe2O3 nanocubes for gas-sensing applications: Feasibility of assessing crucian carp (Carassius auratus) freshness via trimethylamine levels.

Trimethylamine (TMA) is an organic amine with strong pungent smell which is an indicator gas for evaluating fish freshness according to the international standard. In this work, as-synthesize α-Fe2O3 solid nanocubes (NCs), α-Fe2O3 nucleoshell NCs and α-Fe2O3 hollow NCs were used as sensing material to develop an outstanding TMA gas sensor. The response of the α-Fe2O3 hollow NCs sensors towards 20 ppm TMA at 230 ℃ was 6.3. Meanwhile, these sensors showed exceptional response/recovery time, low limit of detection, great selectivity, and outstanding linear relationship. Furthermore, the analysis of gases released during the decomposition of Carassius auratus (0-10 days) was conducted, which demonstrated the assessment of TMA by α-Fe2O3 hollow NCs sensor can evaluate the freshness of Carassius auratus. Such a novel sensor signifies the outstanding application potential in efficient gas-sensing properties of TMA, which will make the tremendous contribution for Carassius auratus product evaluation in the future.

Double-edged sword: effects of human sperm reactive oxygen species on embryo development in IVF cycles.

BACKGROUND: The exact role of sperm reactive oxygen species (ROS) in early embryo development has yet to be fully identified, and most of existing research did not differentiate female infertility factors, ignoring the importance of oocyte quality in embryo development and the large differences in oocyte quality in women with infertility of different etiologies. And there has been no relevant report on whether different types of sperm ROS have distinct effects on embryo development. This study aimed to study the impact of selected sperm ROS, namely, sperm mitochondrial ROS (mROS) and hydrogen peroxide, on human embryo development after conventional in vitro fertilization (IVF) cycles in patients with normo-ovulatory infertility vs. anovulatory infertility. METHODS: This was a prospective investigation including 393 couples underwent IVF cycles, among whom 90 patients had anovulatory infertility and 303 patients had normo-ovulatory infertility in a public university-affiliated in vitro fertilization center. Sperm mROS and hydrogen peroxide testing were performed by flow cytometry and analyzed for their relationship with embryo development indices on days 1-6 after IVF. Multivariate logistic regression analysis was used to control for female potential confounders. The nonlinear effects of sperm ROS on embryo development were analyzed by the Restricted cubic spline (RCS) method. RESULTS: 1. Multivariate linear logistic regression analysis showed that high proportion of mROS positive sperm improved the 2PN rate (OR = 1.325, 95% CI: 1.103-1.595), day 3 embryo utilization rate (OR = 1.362, 95% CI: 1.151-1.614) and good-quality day 3 embryo rate (OR = 1.391, 95% CI: 1.089-1.783) in patients with anovulatory infertility. High percentage of sperm mROS and hydrogen peroxide had adverse effects on cleavage-stage embryo and blastocyst development in patients with normo-ovulatory infertility. 2. For patients with polycystic ovarian syndrome (PCOS) anovulatory infertility, there were significant distinct effects on embryo development indices between sperm mROS and hydrogen peroxide, and the increased rate of sperm mROS improved the good-quality day 3 embryo rate (OR = 1.435, 95% CI: 1.045-1.981); however, high percentage of sperm hydrogen peroxide reduced the blastocyst utilization rate (OR = 0.555, 95% CI: 0.353-0.864) and the good-quality blastocyst rate (OR = 0.461, 95% CI: 0.292-0.718). 3. Multivariate RCS analysis revealed that sperm ROS had a nonlinear (such as a parabolic curve) effect on embryo development in patients with anovulatory infertility (P < 0.05), and either greatly increased or greatly decreased affected cleavage-stage embryo and blastocyst development. The effects of sperm ROS in patients with normo-ovulatory infertility were both linear and nonlinear. CONCLUSIONS: These findings indicate that contrary effects of sperm mROS on embryo development depending on whether patients treated with IVF cycles had normal ovulation. Regardless of whether the patients ovulated normally, increased sperm hydrogen peroxide rate damaged blastocyst development. It is necessary to evaluate male sperm ROS levels and the female ovulatory state to determine an individualized intervention plan before starting cycles, as this may be beneficial for infertile couples.

Rolling Element Bearing Fault Diagnosis by Combining Adaptive Local Iterative Filtering, Modified Fuzzy Entropy and Support Vector Machine.

A new fault feature extraction method for rolling element bearing is put forward in this paper based on the adaptive local iterative filtering (ALIF) algorithm and the modified fuzzy entropy. Due to the bearing vibration signals' non-stationary and nonlinear characteristics, the ALIF method, which is a new approach for the analysis of the non-stationary signals, is used to decompose the original vibration signals into a series of mode components. Fuzzy entropy (FuzzyEn) is a nonlinear dynamic parameter for measuring the signals' complexity. However, it only emphasizes the signals' local characteristics while neglecting its global fluctuation. Considering the global fluctuation of bearing vibration signals will change with the bearing working condition varying, we modified the FuzzyEn. The modified FuzzyEn (MFuzzyEn) of the first few modes obtained by the ALIF is utilized to form the fault feature vectors. Subsequently, the corresponding feature vectors are input into the multi-class SVM classifier to accomplish the bearing fault identification automatically. The experimental analysis demonstrates that the presented ALIF-MFuzzyEn-SVM approach can effectively recognize the different fault categories and different levels of bearing fault severity.