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The objective of this study was to investigate the occurrence of aflatoxin M1 (AFM1) in Chinese liquid milk products. A total of 190 liquid milk samples, including 168 ultrahigh-temperature–treated milk samples and 22 pasteurized milk (PM) samples, were collected in August 2019. A screening assay with the Charm rapid test kit and a confirmation method with high-performance liquid chromatography were used for AFM1 analysis. Nine (4.74%) samples were screened positive, of which 5 (2.11%) samples were confirmed with concentration levels of 0.022 to 0.049 μg/kg. The AFM1 levels confirmed were all below the maximum residue levels set by China, the European Union, the United States, and the Codex Alimentarius Commission. The detection rate of AFM1 in domestic milk samples was 3.39%, while no AFM1 was detected in samples of imported milk. The prevalences of AFM1 detected in three groups of brands were as follows: group I, the major brands of China, 2.70%; group II, the local city domestic brands, 4.55%; and group III, the brands imported into China, 0. The detection rate of AFM1 was significantly higher in PM samples (9.09%) than in ultrahigh-temperature–treated samples (1.19%) (P < 0.05). Although the residue level of AFM1 did not exceed the maximum residue levels in any of the samples, the higher detection rate in local Chinese brands, especially in PM samples, deserves the attention of the Chinese government and consumers. Liquid milk products (n = 190) in the Chinese market were analyzed for aflatoxin M1 (AFM1). Samples were analyzed by the Charm rapid test kit and HPLC. AFM1 was detected in domestic milk samples and pasteurized milk (PM) samples. Concentrations of AFM1 in all affected samples were below the maximum residue levels (MRLs). [ABSTRACT FROM AUTHOR]

In general, the online computation burden of robust model predictive control (RMPC) is very heavy, and the mechanical model of a plant, which is used in RMPC, is hard to obtain precisely in real industry. These issues may largely restrict the applicability of RMPC in real applications. This paper proposes a RBF-ARX (state-dependent Auto-Regressive model with eXogenous input and Radial Basis Function network type coefficients) model-based efficient robust predictive control (RBF-ARX-ERPC) approach to an inverted pendulum system, which is a complete and systematic method for designing robust MPC controller because it integrates the RBF-ARX modeling method and a fast RMPC approach. First, based on the offline identified RBF-ARX model without offset term, two convex polytopic sets are constructed to wrap the globally nonlinear behavior of the system. Then, the optimization problem of implementing a quasi-min–max MPC algorithm including several linear matrix inequalities (LMIs) is formulated, and it is solved offline to synthesize a sequence of explicit control laws that correspond to a sequence of asymptotically stable invariant ellipsoids, of which all the optimization results are stored in a look-up table. During the online real-time control, the controller only needs to carry out a simple state-vector computation and bisection search. The proposed approach is applied to an actual linear one-stage inverted pendulum (LOSIP), which is a fast-responding and nonlinear plant. The real-time control experiments demonstrate the effectiveness of the proposed RBF-ARX model-based efficient RMPC approach. • Combine the RBF-ARX modeling method with a fast RMPC approach. • Propose a complete and systematic method for designing robust MPC controller. • Synthesize a set of control laws corresponding to a sequence of ellipsoids offline. • Controller only need online execute simple computation and bisection search. • The proposed approach was successfully applied to an actual inverted pendulum. [ABSTRACT FROM AUTHOR]

Learning motivation is important for students to master professional knowledge. Teaching strategies play a role in promoting learning motivation and cultivating nursing students' critical thinking. To apply the Attention, Relevance, Confidence, and Satisfaction (ARCS) model-based motivational teaching strategies in a community nursing course and evaluate the effects on learning motivation, critical thinking, and self-learning ability. A mixed-methods study using a quasi-experimental design and descriptive qualitative analysis. Thirty-six third-year nursing students were divided into two groups. The experimental group was exposed to motivational teaching strategies based on the ARCS model in the 12-week community nursing course. The control group received traditional teaching. Students' critical thinking, self-learning ability and academic performance were quantitatively assessed, with t -tests performed to compare learning outcomes. Qualitative outcomes were evaluated through semi-structured interviews, analyzed by using thematic analysis. Students in the experimental group demonstrated significantly greater critical thinking and higher test scores than those in the control group. The self-learning ability and learning motivation of the students exposed to ARCS were also strengthened, and students reported high levels of satisfaction with the motivational teaching strategies. Applying the ARCS model-based motivational teaching strategies in community nursing courses is feasible and associated with improved learning motivation and outcomes among Chinese nursing undergraduates. [ABSTRACT FROM AUTHOR]

46 Streptococcus thermophilus strains, isolated from commercial starters cultures, were studied. The aroma of the fermented milk by these strains was evaluated by quantitative descriptive analysis (QDA). According to its major sensory attribute, the fermented milks were classified into milky-type, creamy-type, cheesy-type, fermented-type and miscellaneous-type groups. One representative sample of each group was analyzed by headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and headspace-solid phase microextraction-gas chromatography-time-of-flight mass spectrometry (HS-SPME-GC-TOF/MS) to describe their volatile compositions. 48 and 72 volatile compounds were identified, respectively. The fingerprint analysis showed that each aroma type had specific volatile compounds. Six important differential volatile compounds including 2,3-butanedione, 2,3-pentanedione, 2-undecanone, octanoic acid, hexanoic acid and 2-hydroxy-3-pentanone were selected as key compounds by principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA), which allowed to discriminate the specific aroma types. These key compounds could be used as indicators to develop fermented milks with specific aroma and flavor features. [Display omitted] • 46 fermented milk samples by S. Thermophilus were divided into 5 aroma types. • GC-IMS and GC-TOF/MS were used to establish the flavor fingerprints of different aroma types. • 6 key compounds of different aroma types were screened out by multivariate statistical analysis. [ABSTRACT FROM AUTHOR]

Previous studies showed that artemisinin (ART) may be useful in the protection against the early development of atherosclerosis, but the effects of ART on vasodilation and eNOS remained unclear. In the current study, we investigated the protective effect of ART on endothelial cell injury induced by oxidative stress and its underlying mechanism via MTT assay, Flow Cytometry Assay, Vasodilation study, Western blotting and vivo assay. We found that pretreatment of human umbilical vein endothelial cells (HUVECs) with ART significantly suppressed H2O2-induced cell death by decreasing the extent of oxidation and MDA activity, activating SOD, increasing NO production and inhibiting caspase 3/7 activity. Meanwhile, we also found that ART was able to activate PI3K/Akt/eNOS pathway. PI3K inhibitor LY294002 or Akt kinase specific inhibitor Akt inhibitor VIII blocked the protective effect of ART. To explore the effect of ART in the damage of vasodilation induced by H2O2 in mice, we treated the aortic ring from C57BL/6 mice with H2O2 with or without ART, the results demonstrated that ART ameliorated endothelium-dependent vasodilation damage induced by H2O2. Taken together, these data suggest that ART is able to protect endothelial function and vasodilation from oxidative damage, at least in part through activation of PI3K/Akt/eNOS pathway. Our findings indicate that artemisinin maybe as a potential therapeutic agent for patients with atherosclerosis. • ART significantly suppressed H2O2-induced cell death by decreasing the extent of oxidation and MDA activity, activating SOD. • ART is able to protect endothelial function and vasodilation via activation of PI3K/Akt/eNOS pathway. • ART maybe as a potential therapeutic agent for patients with atherosclerosis. [ABSTRACT FROM AUTHOR]

A RBF-ARX modeling and robust model predictive control (MPC) approach to achieving output-tracking control of the nonlinear system with unknown steady-state knowledge is proposed. On the basis of the RBF-ARX model with considering the system time delay, a local linearization state-space model is obtained to represent the current behavior of the nonlinear system, and a polytopic uncertain linear parameter varying (LPV) state-space model is built to represent the future system’s nonlinear behavior. Based on the two models, a quasi-min–max MPC algorithm with constraint is designed for output-tracking control of the nonlinear system with unknown steady state knowledge. The optimization problem of the quasi-min–max MPC algorithm is finally converted to the convex linear matrix inequalities (LMIs) optimization problem. Closed-loop stability of the MPC strategy is guaranteed by the use of parameter-dependent Lyapunov function and feasibility of the LMIs. Two examples, i.e. the modeling and control of a continuously stirred tank reactor (CSTR) and a two tank system demonstrate the effectiveness of the RBF-ARX modeling and robust MPC approach. [ABSTRACT FROM AUTHOR]

[Display omitted] • Metagenomics revealed the microbial diversity and functional genes of Ayran. • Ayran of different regions showed varying texture characteristics. • Lactobacillus helveticus was the dominant species in Ayran with high hardness. • Pip and pepE significantly improved the coagulation quality of fermented milk. The complex microflora of traditional fermented milk is crucial to milk coagulation mainly through acid and protease production; however, it is still unclear which microbes and proteases significantly influence the texture of Ayran , a Kazakh artisanal fermented milk in Xinjiang, China. In this study, fifty-nine samples of Ayran were collected and investigated on texture properties. Finally, six Ayran samples with different texture features were screened out, and the taxonomic and functional attributes of their microbiota were characterized by metagenomics. The results showed that the hardness of the fermented milk in Yili Kazakh Autonomous Prefecture was significantly higher than that in other pasture areas. Lactobacillus and Lactococcus were the core genera that affected the coagulation quality of milk. Furthermore, we found that the proline iminopeptidase pip (EC 3.4.11.5) gene of Lactobacillus helveticus and Limosilactobacillus fermentum and the dipeptidase E pepE (EC 3.4.13.21) gene of Lactococcus lactis were most associated with the coagulation quality of fermented milk. Furthermore, positive correlations were observed among the hardness of fermented milk, the activity of the proteases, and the corresponding functional gene expressions. [ABSTRACT FROM AUTHOR]