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A survey of 1800 high school students in Shanghai was conducted to examine the Chinese high school students’ leadership learning needs and strategy choice. The results indicated that most of Chinese high school students have a strong interest in leadership learning. Gender, grade level, and school reputation affect the subjects' leadership learning needs and strategy choices to different degrees. To enhance youth leadership development, school education should expand student leadership development resources to promote active and efficient leadership learning among high school students. Youth education and other related institutions need to play a greater role in enriching the supply of youth leadership learning education.

Finite-time synchronization is concerned for the fractional-order complex-valued fuzzy cellular neural networks (FOCVFCNNs) with leakage delay and time-varying delays. Without using the usual complex-valued system decomposition method, this paper designs the different forms of the controllers by using 2-norm. And we construct the appropriate Lyapunov functional and apply inequality analytical techniques, some new sufficient conditions are obtained to ensure finite-time synchronization of the FOCVFCNNs. The upper bound of setting-time function is obtained. Finally, numerical examples are examined to illustrate the effectiveness of the analytical results.

This paper mainly considers the finite-time synchronization problem of fuzzy inertial cellular neural networks (FICNNs) with time-varying delays. By constructing the suitable Lyapunov functional, and using integral inequality techniques, several sufficient criteria have been proposed to ensure the finite-time synchronization for the addressed (FICNNs). Without applying the known finite-time stability theorem, which is widely used to solve the finite-time synchronization problems for (FICNNs). In this paper, the proposed method is relatively convenient to solve finite-time synchronization problem of the addressed system, this paper extends the research works on the finite-time synchronization of (FICNNs). Finally, numerical simulations illustrated verify the effectiveness of the proposed results.

This paper mainly studies the fixed-time synchronization of Markovian jump fuzzy cellular neural networks with stochastic perturbations, and time-varying delays in the leakage term. By designing delay-dependent controllers with or without fuzzy terms, constructing a suitable stochastic Lyapunov functional and using matrix analysis techniques, this paper derives some novel and useful sufficient conditions to guarantee the fixed-time synchronization of the addressed drive-response systems, and the conditions are delay-dependent, which has less conservative results. The finite time is also independent of the initial states. Finally, numerical examples are given to illustrate the effectiveness of the proposed main results.

To investigate the relationship between serum lutein and type 2 diabetes mellitus (T2DM) and diabetic kidney disease (DKD) in elderly individuals.A total of 60 T2DM patients over 60 years were subgrouped into a DKD group and a non-DKD group according to their urinary microalbumin-to-creatinine ratio (UACR), while 30 age-matched non-T2DM patients were recruited in the control group. Baseline characteristics, laboratory examination results, and serum lutein levels were compared, and their correlations were analyzed. Receiver operating characteristic (ROC) curves were plotted to identify the diagnostic potential of lutein in T2DM and DKD.The lutein level in the T2DM group was significantly lower than that in the control group and was also significantly lower in the DKD group than in the non-DKD group (p 0.001). Lutein levels were negatively correlated with body mass index, glycosylated hemoglobin, fasting blood glucose, triglyceride, and UACR and positively correlated with high-density lipoprotein cholesterol (p 0.05). T2DM patients were divided into four groups according to the quartile of their lutein level. The proportion of T2DM and DKD gradually decreased with increasing lutein levels (p 0.001). The area under the ROC curve of serum lutein in diagnosing T2DM and DKD was 0.880 and 0.779, respectively, with corresponding cut-off values of 0.433 μmol/L and 0.197 μmol/L (p 0.001).The serum level of lutein is negatively correlated with the incidence of T2DM and DKD in the elderly and can serve as a diagnostic marker for T2DM and DKD.

In this paper, the control problem is investigated for discrete time-varying delayed systems with stochastic uncertainty, external disturbance, and two-channel packet dropouts. Sliding mode functions with packet loss probabilities are proposed for the packet loss problem in the sensor–controller channel and the controller–actuator channel. Furthermore, by employing the Lyapunov–Krasovskii functional, some new stability conditions are established in terms of solvable linear matrix inequalities (LMIs), and H∞ performance is analyzed for the sliding mode motion of the system. Meanwhile, a sliding mode controller is designed to drive the system state to the pre-designed sliding surface. Moreover, the designed controller can be robust for two-channel packet dropouts, time-varying delays, stochastic uncertainty and external disturbance. Finally, two numerical examples are given to demonstrate the feasibility of the proposed theoretical method.

Purpose To develop a simple and clinically useful assessment tool for osteoporosis in older women with type 2 diabetes mellitus (T2DM). Methods A total of 601 women over 60 years of age with T2DM were enrolled in this study. The levels of serum sex hormones and bone metabolism markers were compared between the osteoporosis and non-osteoporosis groups. The least absolute shrinkage and selection operator regularization (LASSO) model was applied to generate a risk assessment tool. The risk score formula was evaluated using receiver operating characteristic analysis and the relationship between the risk score and the bone mineral density (BMD) and T-value were investigated. Results Serum sex hormone-binding globulin (SHBG), cross-linked C-telopeptide of type 1 collagen (CTX), and osteocalcin (OC) were significantly higher in the osteoporosis group. After adjustment for age and body mass index (BMI), SHBG was found to be correlated with the T-value or BMD. Then, a risk score was specifically generated with age, BMI, SHBG, and CTX using the LASSO model. The risk score was significantly negatively correlated with the T-value and BMD of the lumbar spine, femoral neck, and total hip (all P Conclusion A risk score using age, BMI, SHBG, and CTX performs well for identifying osteoporosis in older women with T2DM.

This paper is concerned with the finite-time synchronization of coupled networks with time-varying delays. We work without applying the finite-time stability theorem, which is widely used in finite-time synchronization for complex networks or finite-time consensus problems for multi-agent systems. We construct a novel Lyapunov functional and apply some new analytical techniques. Sufficient conditions are obtained to ensure synchronization within a setting time with no Zeno behaviors. The obtained conditions do not contain any uncertain parameter. The controllers are presented based on event-driven strategies, which can significantly reduce the communication consumption and the frequency of the controller updates. And the setting time is related to initial values of the network. Finally, numerical examples are examined to illustrate the effectiveness of the analytical results.

Type 2 diabetes (T2D) is a glucose regulation disorder that has significantly enhanced mortality and the global disease burden. The prevalence of T2D has increased worldwide and is higher in the elderly. The function of pancreatic islets decreases with age, which is one important reason for the occurrence of diabetes in the elderly. Recently, peptidome analysis has attracted attention. However, the role of age-related peptides in pancreatic dysfunction has not been investigated extensively. Here, we conducted a comparison of endogenous peptides between pancreas from adult and aging mice by liquid chromatography tandem mass spectrometry (LC-MS/MS). A total of 2,089 peptides originating from 1,280 protein precursors were identified, of which 232 were upregulated and 183 were downregulated in the aging mice (fold change ≥ 2 and p < 0.05), suggesting that the expression of pancreatic peptides in mice varied with age. The molecular weight of most peptides was

This cross-sectional study aimed to examine changes in thyroid-stimulating hormone (TSH) concentration over age in China and investigate relationship between TSH and risk factors for cardiovascular disease (CVD) among euthyroid subjects. TSH, free triiodothyronine (FT3), free thyroxine (FT4), blood lipid, and glucose were measured. 7,693 individuals were subdivided into different age groups. Associations between TSH and CVD risk factors [age, body mass index (BMI), systolic and diastolic blood pressure, total cholesterol (TC), triglycerides, low density lipoprotein-cholesterol (LDL-C) and high density lipoprotein-cholesterol (HDL-C) and fasting plasma glucose (FPG)] were evaluated with Pearson correlation analysis. Results showed that 2.5th percentile for TSH was consistent across age groups, whereas 97.5th percentile increased in subjects older than 40 years with upper limit being 6.83 mIU/L in subjects aged 60-69 years and 8.07 mIU/L in those older than 70 years. The age-specific upper limits reclassification rate was higher in all age bands as compared to the common cut-off value. TSH was positively associated with age, SBP, DBP, TC and LDL-C and negatively with FT3 and FT4. Serum TSH within new reference range had a linear correlation with SBP, TC and LDL-C in subjects aged

AIM This cross-sectional study aimed to investigate the differences in β-cell function and insulin sensitivity between newly diagnosed aged and middle-aged type 2 diabetes mellitus (T2DM) patients. METHODS A total of 206 newly diagnosed T2DM patients aged ≥60 years (A-DM group) and 206 newly diagnosed sex- and glycated hemoglobin-matched T2DM patients aged

Naringenin exerts anti-inflammatory, hypolipidemic, and hepatoprotective effects; however, it shows low oral bioavailability because of poor water solubility. In this work, cocrystals of naringenin were formed to address these issues. Using the solution crystallization method, various naringenin cocrystals were prepared with different cocrystal coformers, including naringenin-nicotinamide, naringenin-isonicotinamide, naringenin-caffeine, naringenin-betaine, and naringenin-L-proline. The formation of these cocrystals was assayed by using DSC, XRD, and FT-IR spectroscopy. The stoichiometric ratio of naringenin and the CCFs in the corresponding cocrystals was investigated by NMR. The solubility of naringenin, as well as its dissolution rate, was markedly improved by forming cocrystals. The oral bioavailability of naringenin administered as naringenin-L-proline and naringenin-betaine cocrystals was achieved significantly greater than that of pure naringenin (p

Metabolic syndrome (MS) and non-alcoholic fatty liver disease (NAFLD) have been identified as risk factors affecting serum sex hormone binding globulin (SHBG) levels. We conducted this cross-sectional study to delineate whether MS or NAFLD has more impact on circulating SHBG levels in type 2 diabetes (T2D) patients. Anthropometric and biochemical parameters including serums SHBG, testosterone (TT), liver enzymes, lipids, insulin, C-peptide and plasma glucose were measured. Regardless of the MS status, SHBG level was significantly lower in NAFLD patients than in non-NAFLD patients (P

This paper is concerned with mean square exponential synchronization for a class of Markovian switching complex networks (MSCNs) with time-varying delay and stochastic noise under feedback control and M-matrix approach. Firstly, a class of MSCNs with time-varying delay and stochastic noise is considered. Secondly, by using M-matrix method and feedback control scheme, several sufficient conditions of mean square exponential synchronization are derived. At last, two numerical examples and simulations are given to illustrate the effectiveness of the theoretical results.

In this paper, finite-time synchronization problem is considered for a class of Markovian jump complex networks (MJCNs) with partially unknown transition rates. By constructing the suitable stochastic Lyapunov–Krasovskii functional, using finite-time stability theorem, inequality techniques and the pinning control technique, several sufficient criteria have been proposed to ensure the finite-time synchronization for the MJCNs with or without time delays. Since finite-time synchronization means the optimality in convergence time and has better robustness and disturbance rejection properties, this paper has important theory significance and practical application value. Finally, numerical simulations illustrated by mode jumping from one mode to another according to a Markovian chain with partially unknown transition probability verify the effectiveness of the proposed results.

In this study, the authors study the finite-time cluster synchronisation problem for a class of Markovian switching complex networks with stochastic noise perturbations. By constructing the suitable stochastic Lyapunov–Krasovskii functional, using finite-time stability theorem, inequality techniques and the properties of Weiner process, sufficient conditions are obtained to ensure finite-time cluster synchronisation for the complex networks with or without time delays. The effects of control parameters on cluster synchronisation speed and time delays are also analysed. Since finite-time cluster synchronisation means the optimality in convergence time and has better robustness and disturbance rejection properties, this study has important theory significance and practical application value. Finally, numerical examples are examined to illustrate the effectiveness of the analytical results.

This paper concerns the stability analysis problem for stochastic delayed switched genetic regulatory networks (GRNs) with both stable and unstable subsystems. By employing the piecewise Lyapunov functional method combined with the average dwell time approach, we show that if the average dwell time is chosen sufficiently large and the derivative of the Lyapunov-like function for unstable subsystems is bounded by certain kind of continuous function, then exponential stability criteria of a desired degree are guaranteed. The derived results show that the minimal average dwell time is proportional to the time delays. Finally, an example is given to illustrate the effectiveness of the derived results.

In this paper, the problem of delay-dependent @a-dissipativity analysis is investigated for a general class of singular systems with Markovian jump parameters and mode-dependent mixed time-delays. By using the novel Lyapunov-Krasovskii functional and stochastic analysis technology, the new criteria are derived to guarantee that the addressed singular systems are stochastically admissible and strictly (Q,R,S)-@a-dissipative. Numerical examples are presented to illustrate the effectiveness and less conservativeness of the proposed theoretical results.

In this paper, stabilization and synchronization control problems are considered for Markovian jumping neural networks with mode-dependent mixed time delays subject to quantization and packet dropout. By using the novel Lyapunov–Krasovskii functional, stochastic analysis technology and quantization feedback method, the stabilization problem is solved for the addressed neural networks firstly. Also, it is assumed that system state is quantized before being communicated. Then the sufficient condition for the existence of an admissible controller is established to ensure the asymptotic synchronization of the resulting closed-loop coupled neural networks. Finally, two numerical examples are presented to show the validity of our theoretical analysis results.

We developed a sensitive and rapid method for determination of ferulic acid, caffeic acid, vanillic acid, and paeoniflorin in rat plasma based on ultra high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC–MS/MS). The separation of the four compounds was carried out on an AcQuity UHPLC™ BEH C18 column using a mobile phase consisting of acetonitrile and water (containing 0.1% formic acid). Electrospray ionization in positive and negative ion mode and multiple reaction monitoring was used to identify and quantify active components. All calibration curves gave good linearity (r > 0.991) over the concentration range from 4.24–2875 ngmL-1 for all components. The precision of the in vivo study was evaluated by intraday and interday assays and the percentages of RSD were all within 10.6%. The recovery ranged from 60.2 to 77.9%. The method was successfully applied to pharmacokinetic study of all three aromatic acids and one monoterpene in rat plasma. Furthermore, we compared the pharmacokinetics profile of the four compounds in normal and primary dysmenorrhea rats' plasma following oral administration of Shaofu Zhuyu decoction (SFZYD) and its ethanol supernatant extract (SFE).

In this paper, feedback control problem is considered for networked systems with discrete, infinite distributed delays and sampled-data. A Markov chain is used to characterize the random sampled measurement process of the networked control systems. In addition, an event-driven transmitter is introduced to transmit the control signal according to the measurement sampling period. Based on Lyapunov functional and the matrix analysis techniques, several sufficient conditions are given to ensure the asymptotical stability in the mean square of the addressed control systems. Furthermore, a novel output feedback controller is proposed with both sampling and event-driven transmitter-induced delay indexes. Finally, a simulation example is provided to illustrate the effectiveness of the theoretical results and the proposed method.

Finite-time synchronization is studied for delayed complex networks with stochastic disturbance. Based on the finite-time stability theorem, some sufficient conditions are obtained to ensure finite-time synchronization for Markovian jump complex networks with time delays and partially unknown transition rates. Finally, the effectiveness of the proposed method is demonstrated by illustrative examples.

In this present study, a sensitive and rapid UPLC-MS/MS method was developed for simultaneous quantification of paeoniflorin, albiflorin, ferulic acid, tetrahydropalmatine, protopine, typhaneoside and senkyunolide I in Beagle dog plasma after oral administration of the Shao-Fu-Zhu-Yu Decoction. Chloramphenicol and clarithromycin were used as internal standards. Plasma samples were processed by protein precipitation with methanol. The separation was performed on an Acquity BEH C18 column (100mm×2.1mm, 1.7μm) at a flow-rate of 0.4mL/min, using 0.1% formic acid-acetonitrile as mobile phase. Method validation was performed as per Food and Drug Administration guidelines and the results met the acceptance criteria. After validation, this method was successfully applied to a pharmacokinetic study. The results showed that the apparent plasma clearance of paeoniflorin, albiflorin, typhaneoside and senkyunolide I were significantly higher than others. Double peak was observed in plasma concentration curves of tetrahydropalmatine, the ferulic acid had a good absorption in Beagle dog plasma, and senkyunolide I was detected in plasma from the first blood sampling time (15min) and rapidly reached Tmax. The compound of typhaneoside has a low bioavailability according to the results.

In this paper, we investigate the synchronization and parameter identification of chaotic system with unknown parameters and mixed delays. A new approach is proposed for designing a controller and a update rule of unknown parameters based on a special matrix structure, and the synchronization and the parameter identification are realized under the controller and the update rule. Numerical simulations are carried out to confirm the effectiveness of the approach. A significant advantage is that the process of designing a controller and a update rule become very clear and easy by the proposed approach.

Background Siwu decoction categorized formulae (SWDCF) are widely used for treating gynecological diseases. This study aims to elucidate the differences of bioactive constituents in SWDCF by ultra-high performance liquid chromatography coupled with time-of-flight mass spectrometry (UPLC - QTOF - MS /MS) and HPLC-DAD. Methods An efficient method based on UPLC - QTOF - MS /MS was developed for identifying the chemical profiles of SWDCF. HPLC-DAD method was used for quantifying seven chemical markers in SWDCF. Results Eighty four components were identified or characterized, including ten organic acids, thirty glycosides (monoterpene or iridoid or phenylpropanoids glycosides), fourteen lactones, eighteen flavonoids, and eleven alkaloids in the complex system. The datasets of tR-m/z pairs, ion intensities and sample codes were processed with supervised orthogonal partial least squared discriminant analysis to compare these decoction samples. After a clear classification was established, OPLS-DA was performed and 16 common components with relative quantity in SWDCF samples were determined. Gallic acid, protocatechuic acid, vanillic acid, caffeic acid, paeoniflorin, ferulic acid, and senkyunolide I were selected as the chemical markers to identify SWDCF by HPLC-DAD. Conclusion The chemical profiles with 84 components in SWDCF, including monoterpene glycosides, acetophenones, galloyl glucoses, even some isomers in the complex system were characterized by UPLC–QTOF–MS/MS.

This paper is concerned with robust stability problem for Markovian jump singular time-delay systems with disturbances. In terms of strict linear matrix inequality(LMI), a new necessary and sufficient condition is proposed for the unforced Markovian jump singular system to be stochastically admissible. Based on this, the sufficient conditions are obtained for the existence of performance, which guarantees the singular Markovian jump systems with disturbances to be regular, impulse-free and stochastically stable. One numerical example is given to demonstrate the applicability of the proposed method.