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It is the first report about fault-tolerant-based prescribed performance control of switched nonlinear systems under multiple faults. The concerned faults include not only external faults but also actuator faults. In the process of backstepping control design, prescribed performance control is fully considered, and the combination of unknown nonlinear functions is estimated by multi-dimensional Taylor network. Finally, the developed adaptive fault-tolerant control strategy guarantees the boundedness of all controlled signals while prescribed tracking performance is satisfied. In an effort to further manifest the validity of the fault-tolerant controller, a numerical simulation and a practical simulation are introduced.

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The finite-time control of switched nonlinear systems subject to multiple objective constraints is investigated in this article. Firstly, with the aim of dealing with the major challenge brought by multiple objective constraints, the time-varying and asymmetric barrier function is designed, which transforms multiple objective constrained systems into unconstrained systems. Secondly, the dynamic surface control technique is introduced into the backstepping design process, and the error generated in the filtering process is reduced by constructing the error compensation systems. Then, an adaptive finite-time controller based on multi-dimensional Taylor network (MTN) is proposed. The controller proposed in this article can avoid the "singularity" problem and ensure that the objective functions never violate constraints. Finally, the effectiveness of the finite-time control strategy proposed in this article is verified by the aircraft system simulation.

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BACKGROUND: Z score utility is emphasized in classifying coronary artery lesions in Kawasaki disease patients. The present study is the largest such multicenter Chinese pediatric study about coronary artery diameter reference values and Z score regression equation to date. It is useful in Chinese pediatric echocardiography. METHODS: A multicenter cohort was assembled, which consisted of 852 healthy children between 1 month and 17 years of age, ten children were excluded because their ultrasound images were not clear, or lost in following up. Diameters of the right coronary artery, left coronary artery, and left anterior descending coronary artery were assessed using echocardiography. Data were body surface area (BSA)-corrected using BSA calculated via either the Stevenson BSA formula or the Haycock BSA formula. Coronary artery diameter reference values and Z score regression equations were established for use in the Chinese pediatric population. RESULTS: No difference was observed between coronary artery diameter data corrected using BSAste or BSAhay. Of the five assessed regression models, the exponential model exhibited the best fit and was therefore selected as the basis for derivation of the SZ method. When comparing Z scores, those produced by the SZ method conformed to the standard normal distribution, while those produced by the D method did not. In addition, there was a statistically significant difference between Z scores produced by the SZ and D methods (P < 0.05). CONCLUSIONS: Coronary artery diameter reference values for echocardiography were successfully established for use in the Chinese pediatric population, and a Z score regression equation more suitable for clinical use in this population was successfully developed.

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Procambarus clarkii was introduced into China as an important aquatic product in early 20th century. It has characteristics of high fertility, rapid growth, adaptability and digging burrows, which could cause damage of crops, cropland and facilities, decrease local biodiversity and thus threaten local ecosystem. Thus, predicting the potential distribution of P. clarkii in response to climate change was essential for preventing and monitoring this species. Based on the distribution of P. clarkii, the maximum entropy (MaxEnt) and genetic algorithm for rule-set production (GARP) models were used to predict its distribution in China under current climate and four climate scenarios (RCP 2.6, RCP 4.5, RCP 6.0, RCP 8.5) in two periods, 2041-2060 and 2061-2080. Then, the modeling results were tested by ROC curves. The results showed that under current climate, the highly suitable region for distribution predicted by the MaxEnt and GARP models were Shanghai, Jiangsu, Zhejiang and Anhui along the Yangtze River. The main environmental variables affecting its distribution were mean temperature of the coldest quarter, minimum temperature of the warmest month, and temperature seasonality, maximum temperature of the warmest month, precipitation of the driest month. Under the future climate scenarios, the suitable area of P. clarkii distribution varied in 2061-2080. The total suitable area of P. clarkii would increase under RCP2.6 and RCP 4.5, whereas under RCP 8.5 the suitable area of P. clarkii would increase, and then decrease. In RCP 6.0, there was no change. The suitable areas of P. clarkii would disperse to different latitude areas and migrate toward high altitude.

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INTRODUCTION: We aimed to estimate the frequency of each AT(N) (ß-amyloid deposition [A], pathologic tau [T], and neurodegeneration [N]) profile in different clinical diagnosis groups and to describe the longitudinal change in clinical outcomes of individuals in each group. METHODS: Longitudinal change in clinical outcomes and conversion risk of AT(N) profiles are assessed using linear mixed-effects models and multivariate Cox proportional-hazard models, respectively. RESULTS: Participants with A+T+N+ showed faster clinical progression than those with A-T-N- and A+T±N-. Compared with A-T-N-, participants with A+T+N± had an increased risk of conversion from cognitively normal (CN) to incident prodromal stage of Alzheimer's disease (AD), and from MCI to AD dementia. A+T+N+ showed an increased conversion risk when compared with A+T±N-. DISCUSSION: The 2018 research framework may provide prognostic information of clinical change and progression. It may also be useful for targeted recruitment of participants with AD into clinical trials.

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BACKGROUND: Quantitative assessment of ventricular function in children with single ventricles is both difficult and subjective because of asymmetric ventricular geometry. The Doppler myocardial performance index (MPI) allows the assessment regardless of ventricular shape. This study was designed to evaluate the feasibility of MPI in assessing ventricular function in children with single ventricles before and after total cavopulmonary connection (TCPC). METHODS: Subjects consisted of 161 pediatric patients with single ventricles and 80 normal children without heart disease. The maximum positive rate of ventricular pressure change (Max dp/dt) was obtained in 58 patients by cardiac catheterization. Sixty-eight children with single ventricles received TCPC. MPI was calculated from Doppler tracings of ventricular inflow and outflow, then MPI of single ventricles before and after surgery and normal heart were compared. RESULTS: Normal MPI value was 0.30+/-0.08 in the left ventricle and 0.26+/-0.08 in the right ventricle. Compared to normal children, MPI was significantly higher in 161 children with single ventricles (0.54+/-0.11, P<0.001). MPI correlated inversely with Max (dp/dt) (r=-0.77, P<0.01), and was positively related to age (r=0.54, P<0.01) in patients with single ventricles. MPI did not differ significantly before and after surgery in 68 patients with single ventricles (0.55+/-0.21 vs 0.51+/-0.20, P>0.05). However, MPI in 48 patients of <6 years old decreased significantly (0.55+/-0.21 vs 0.48+/-0.18, P<0.05), suggesting improved ventricular function. CONCLUSIONS: Compared to normal children, ventricular function is impaired in patients with single ventricles and may worsen with age. MPI provides an accurate method for assessing ventricular function in children with single ventricles before and after TCPC.

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Changes of lipid peroxidation reaction and NK cell activity in spleen of CCl4-induced liver injury mice with adding orgnoselenium from Se-enriched lactobacillus were studied to discuss the protective effect of orgnoselenium and its mechanism. Sixty healthy mice (female: male=1:1) were chosen and divided randomly into four groups: control group (group C), orgnoselenium group (group Se), CCl4-injection group (group CCl4) and CCl4-injection plus orgnoselenium group (group CCl4-Se). The liver injury was induced by abdominal injection of CCl4 (0.07ml/100g body weight) on every other day over four weeks. The spleens were collected at the 2nd and 4th week, and spleen NK cell activity, spleen homogenate GSH-Px, SOD, CAT activities and MDA concentration were determined. The results showed that during the entire experimental period, spleen homogenate GSH-Px, SOD and CAT activities in groups C, Se and CCl4-Se were higher or significantly higher than that in group CCl4, and three antioxidant enzyme activities in groups Se and CCl4-Se had no apparent differences from that in group C except that there were significant increases of SOD activity at the 4th week. Spleen homogenate MDA content of group CCl4 increased markedly compared with that of groups C, Se and CCl4-Se, MDA level of group CCl4-Se was close to that of group C, and that of group Se was lower. During the entire experimental period, NK cell activity of group Se was the highest and significantly higher than that of group C at the 4th week, a lowest value was observed in group CCl4, which was lower or markedly lower than that of groups C, Se and CCl4-Se, there were no significant differences between group CCl4-Se and group C. It is suggested that orgnoselenium from Se-enriched lactobacillus can enhance antioxidation ability in normal mice and play an effective role by means of improving and enhancing the spleen antioxidation enzymes and NK cell activities in the process of intervening liver injury.

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Changes of some immune-mediators in liver tissue homogenate and plasma of liver injury mice injected with CCl4 and its mechanism in the liver injury process induced by CCl4 were studied. Thirty healthy mice with half of female and male were chosen and divided randomly into two groups which were control group (group C) and CCl4-injecting group (group CCl4). The liver injury was induced by abdominal injection of CCl4 (0.07 ml/100 g body weight) on every other day over six weeks. The blood and liver were collected at the 2nd, 4th and 6th week, respectively, and liver homogenate cAMP, cGMP levels and MDA concentration as well as plasma IL-2 and TNF-alpha levels were determined. The results show that during the entire experimental period, cAMP level decreased or markedly decreased in group CCl4. After the 2nd week of CCl4-injecting, cGMP was lower or significantly lower in group CCl4 than in group C; cAMP/cGMP ratio tended to drop, and was low or significantly low to group C; and MDA content was significantly higher in group CCl4 than in group C. During the whole experimental period, a marked decrease of plasma IL-2 in group CCl4 was seen, and plasma TNF-alpha of group CCl4 was superior to that of group C. It is suggested that the violent changes of immune-mediators including cAMP, cGMP, TNF-alpha and IL-2 etc induced by CCl4 may play an important role in the induction of liver injury in mice.

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Sixty healthy Sprague-Dawley male rats were used and divided randomly into control group (group C), cadmium loading group with medium dose (group M) and cadmium loading group with high dose (group H). Groups C, M and H were orally dosed daily with 0, 5 and 10 mg/kg of cadmium for over 6 weeks. Effects of cadmium loading on testis and endocrine function of reproduction in male rats were studied. The results showed that the zinc content decreased slightly in testis and plasma, and the cadmium concentration increased significantly in the testis of groups M and H; while the plasma levels of cadmium and zinc had no obvious difference as compared with those of group C; daily sperm production in the testis of group H decreased markedly during week 3 of cadmium loading, and was significantly lower in groups M and H as compared to that in group C during week 6; alkaline phosphatase (ALP) in group H and lactate dehydrogenase-X (LDH-X) in groups M and H were markedly lower compared to those of group C; plasma testosterone (T) level in both cadmium loading groups decreased and was low or significantly lower than that in group C; follicle stimulating hormone (FSH) and luteinizing hormone (LH) levels had no apparent difference between the three groups. It is suggested that the gradual accumulation of cadmium in testis tissue induced by chronic cadmium loading results in changes in some enzyme activity, a decrease in sperm production, and defect of endocrine function activity in the testis.

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