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The overhead crane systems contain parameter uncertainties and external disturbances, which will affect the control performance of the systems. To overcome this problem, an interval type-2 Takagi–Sugeno (T-S) fuzzy linear quadratic regulator (LQR) approach is proposed for overhead crane system in this paper. First, an interval type-2 T-S fuzzy model is constructed based on the nonlinear dynamic model of the overhead crane system. The type-2 model can capture the system uncertainties. Second, the fuzzy LQR is designed on the basis of the fuzzy model and the asymptotic stability of the closed-loop system is analyzed using Lyapunov method. Finally, simulations and experiments are studied. The results show that the proposed method can give the overhead crane system faster trolley positioning speed, smaller load swing, and better anti-disturbance ability than the existing LQR control method.

Due to the complex structure of the tower crane and the signal noise, it is difficult to estimate and predict the real position signal, which may lead to inaccurate positioning of the tower crane trolley. A tower crane positioning algorithm based on D-S evidence theory and unscented Kalman filter (DS-UKF) is established and developed. First, the nonlinear dynamic model, state equation, and detection equation of the tower crane are constructed based on the complex structure of the tower crane. Second, the arm angle is estimated, and the distance between the trolley and the root of the arm is positioned. Finally, in order to calculate the weight of a single sensor, the D-S evidence theory is used to process the measurement information of the sensor and the estimated value of the filter. The Kalman filter, which has good signal tracking and estimation ability, is used to predict and estimate the position of the trolley. The accurate positioning of the tower crane trolley is realized through the organic fusion of information. The simulation results show the effectiveness of the DS-UKF positioning algorithm.

Brood parasitic cuckoos and their hosts serve as model systems for studying host–parasite coevolution. Egg-rejection behavior constitutes an effective defense against brood parasitism, but some host species show phenotypic plasticity in egg-rejection behavior. Direct exposure to a cuckoo near the nest can increase egg-rejection likelihood, and long-term studies have shown that increased the egg-rejection rates generally correlate with higher parasite prevalence. However, it remains unclear whether such increases result from interactions between parasites and hosts, as these can be surprisingly common, or whether the mere presence of cuckoos in the breeding area is sufficient. Daurian redstarts Phoenicurus auroreus are a common host of the common cuckoo Cuculus canorus that defend against cuckoo parasitism mainly by ejecting the parasitic egg from the nest. This species is unique, as its first breeding attempt of the year takes place before the arrival of cuckoos, excluding the possibility for direct interactions. We simulated the ambient presence of cuckoos or hoopoes Upupa epops (control) in sub-populations of redstarts during their first egg-laying period by presenting taxidermic models and playing back vocalizations. Redstarts in cuckoo-treated plots showed significantly higher egg-ejection rates than individuals in control plots, even though females in both groups were equally likely to recognize the parasitic egg. Among females that did recognize the parasitic egg, those exposed to the cuckoo treatment were more likely to eject it than those exposed to the control treatment. Our results demonstrate unequivocally that the mere presence of cuckoos in the environment is sufficient to provoke egg-ejection behavior.

The arms race between brood parasites and their hosts provides a classic model to study coevolution. Hosts often reject the parasitic egg, and brood parasites should therefore select host nests in which the colour of the eggs best matches that of their own. Although this hypothesis has received some support, direct experimental evidence is still lacking. Here, we report on a study of Daurian redstarts, which show a distinct egg-colour dimorphism, with females laying either blue or pink eggs. Redstarts are often parasitized by common cuckoos, which lay light blue eggs. First, we showed that cuckoo eggs were more similar in spectral reflectance to the blue than to the pink redstart egg morph. Second, we report that the natural parasitism rate was higher in blue than in pink host clutches. Third, we performed a field experiment in which we presented a dummy clutch of each colour morph adjacent to active redstart nests. In this set-up, cuckoos almost always chose to parasitize a blue clutch. Our results demonstrate that cuckoos actively choose redstart nests in which the egg colour matches the colour of their own eggs. Our study thus provides direct experimental evidence in support of the egg matching hypothesis.

To explore the value of T2 mapping in the dynamic quantitative evaluation of renal ischemia- reperfusion injury (IRI).Forty-eight healthy New Zealand rabbits were randomly divided into IRI group (n = 40) and control group (n = 8). Rabbits in the IRI group underwent left renal artery clamping for 60 minutes. Rabbits underwent MRI examinations (T2WI and T2 mapping) before and 1, 12, 24, and 48 hours after IRI. The inter-observer and intra-observer reproducibility of the T2 values were assessed using the intraclass correlation coefficient (ICC) with 95% confidence interval (CI). Correlations between the T2 value of the renal outer medulla and injury scores were assessed by Spearman correlation analysis. The repeated measures analysis of variance was used to compare the differences in T2 values of the IRI and control group across the different time points.Both of the intra-observer (ICC = 0.97, 95% CI 0.95-0.99) and inter-observer reproducibility (ICC = 0.92, 95% CI 0.86-0.96) were excellent for T2 values. The T2 value of the renal outer medulla was moderately positive correlated with tubular epithelial edema (ρ = 0.686, p0.001). In IRI group, T2 values of the renal outer medulla were increase at 1 h after IRI (p = 0.001) and were decrease from 1 h to 12 h (p = 0.002). At 1 h after IRI, the T2 values of the renal outer medulla for the IRI group were higher than those for the control group (p0.001).T2 mapping can reflect the dynamic changes of renal parenchyma in an animal model of IRI and be used to assess the early renal IRI.

Egg rejection behaviour is a host strategy adopted by birds against brood parasitism. The optimal acceptance threshold hypothesis predicts that, when the frequency or risk of parasitism increases, host acceptance thresholds should become more restrictive. Here, we investigated egg rejection behaviour in the Daurian redstart, a cavity-nesting host of the common cuckoo, Cuculus canorus. In a Daurian redstart population located in the northern cold-temperate zone of China where redstarts have two peaks of egg laying during the breeding season, cuckoos can only parasitize redstart nests during the second egg-laying peak due to their late arrival on the breeding grounds. We artificially simulated brood parasitism by introducing a model cuckoo egg into a redstart nest during both egg-laying peaks to test the prediction that redstarts should reject eggs at a greater rate during the second than the first egg-laying peak. In accordance with the optimal acceptance threshold hypothesis, Daurian redstarts showed significantly higher egg rejection rates during the second egg-laying peak. This result indicates that temporal variation in egg rejection behaviour by Daurian redstarts may be an adaptive response to seasonal change in risk of cuckoo parasitism. To our knowledge, this is the first study showing that the egg rejection rate of a host population increases with increasing risk of cuckoo parasitism within a breeding seas.

Cerebral lateralization, which is often reflected in an individual's behavioral laterality (e.g., handedness and footedness), may bring animals certain benefits such as enhanced cognitive performance. Although the lateralization-cognition relationship has been widely studied in humans and other animals, current evidence supporting their relationship is ambiguous and warrants additional insights from more studies. Moreover, the lateralization-cognition relationship in non-human animals has been mostly studied in human-reared populations, and investigations of wild populations are particularly scarce. Here, we test the footedness of wild-caught male yellow-bellied tits (Pardaliparus venustulus) and investigate its association with their performance in learning to solve a toothpick-pulling problem and a drawer-opening problem. The tested birds showed an overall trend to gradually spent less time solving the problems, implying that they learned to solve the problems. Left- and right-footed individuals showed no significant differences in the latency to explore the experimental apparatuses and in the proportions that completed and did not complete the tasks. However, the left-footed individuals learned faster than the right-footed individuals in the drawer-opening experiment, indicating a potential cognitive advantage associated with left-footedness. These results contribute to the understanding of the behavioral differences between differently footed individuals and, in particular, the relationship between lateralization and cognitive ability in wild animals.

PURPOSE To explore if R2 ' mapping can assess renal hypoxia in rabbits with ischemia reperfusion injury (IRI). METHODS Forty rabbits were randomly divided into 4 groups according to the clipping time: the sham group and 45 min, 60 min, and 75 min for the mild, moderate, and severe groups (with n = 10 each group), respectively. Intravenous furosemide (FU) was administered 24 h after IRI. All rabbits were performed 5 times (IRIpre , IRI24h , FU5min , FU12min , and FU24min ) with a 3.0 Tesla MR. The R2 ' values and the hypoxic scores were then recorded. The repeated measurement analysis of variance and Spearman correlation analysis was used for statistical analysis. RESULTS Compared to the baseline, the medullary R2 ' values increased significantly 24 h after the IRI (baseline 19.31 ± 1.21 s-1 , mild group 20.05 ± 1.26 s-1 , moderate group 25.38 ± 1.38 s-1 , and severe group 25.79 ± 1.10 s-1 ; each P < .001). FU led to a significant decrease in the medullary R2 ' value (sham group 11.17 ± 4.33 s-1 , mild group 7.80 ± 0.74 s-1 , moderate group 3.92 ± 0.28 s-1 , and severe group 3.82 ± 0.23 s-1 ; each P < .05). Quantitative hypoxic scores revealed significant differences among the 4 groups in the outer medulla (P < .001 each). The medullary R2 ' differences (before and after intravenous FU) were significantly correlated with the hypoxic scores, respectively (P < .001). CONCLUSION R2 ' mapping can evaluate the renal hypoxia in the procession of IRI in rabbits and might serve as a quantitative biomarker for IRI.

Background To explore whole-liver histogram analysis (HA) with blood oxygen level-dependent functional magnetic resonance imaging (BOLD-fMRI) in evaluating and diagnosing hepatic fibrosis (HF) in a CCl4-induced rabbit model. Methods One hundred rabbits were classified as CCl4-induced HF groups (n=80) and control group (n=20), and were scheduled for BOLD-fMRI examination on a 3.0T scanner. Whole-liver HA metrics, including the mean, median, skewness, kurtosis, inhomogeneity, entropy, and nth percentiles, were extracted from the R2* map. Parameters were compared among the different HF stages using receivers operating characteristic analysis and Mann-Whitney U-test. Results In all, 17, 18, 19, 17, and 15 rabbits were pathologically diagnosed as F0, F1, F2, F3, and F4, respectively. HA parameters, including the median, inhomogeneity, entropy, and the 75th and 90th percentiles of the BOLD R2* map, demonstrated significant positive correlations with the fibrosis stage (r=0.226-0.718, P≤0.039). The 75th percentiles demonstrated higher diagnostic efficacy than the other HA parameters in fibrosis staging, with an AUC value of 0.86 for ≥ F1, 0.87 for ≥ F2, 0.87 for ≥ F3, and 0.86 for ≥ F4. Conclusions BOLD-fMRI HA provides increased diagnostic performance in staging HF, especially for the 75th percentiles.

An integral state feedback control method based on T-S fuzzy model is proposed for nonlinear and unstable magnetic levitation ball system in this paper. Firstly, the fuzzy model of the magnetic levitation ball is derived from the nonlinear dynamic model by using the sector nonlinearity, and the local controller is designed by using the integral state feedback control. The global controller is constructed by a parallel distributed compensation (PDC) method, and the feedback gain is obtained using a linear matrix inequality (LMI). Finally, the integrated state feedback controller is applied to the position control of the magnetic levitation ball system, and a dSPACE real-time control platform is established for experimental research. The simulation and experiment are performed to prove that the designed controller can levitate the ball stably, and has better control performance.

A two-degree-of-freedom (2-DOF) control method with parallel control structure (PCS) is proposed for inverse response process plus time delay. The parallel control structure decouples the set-point tracking response from disturbance rejection response. Set point tracking control uses the method of internal model control (IMC) based on PCS. This method not only eliminates the non minimum phase parts in the denominator of the characteristic equation, but also has only one adjustable parameter which sets controller parameter using dynamic performance index, which makes the system have a good tracking performance. Disturbance rejection controller uses the principle of internal model controller, and the maximum sensitivity function is also applied to set the controller parameter. It avoids the blindness of parameter selection and improves the robustness and disturbance rejection performance of the system. Theoretical analysis and simulation results show that the proposed method presents good set-point tracking performance, disturbance rejection performance and robustness.

The double pendulum overhead crane system is a complex nonlinear system. In this paper, T-S fuzzy model is established for the double pendulum overhead crane system to describe the nonlinear characteristics of the controlled system. In order to reduce the influence of external disturbances and internal uncertainties on the control performance, a H ∞ controller for positioning and anti-swing of double pendulum overhead crane is proposed. The simulation results show that the proposed method can not only ensure the accurate positioning of the trolley, but also suppress the two-stage swing, and has good robustness and anti-disturbance performance.

ObjectivesTo explore the differences between intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) and diffusion-weighted imaging (DWI) in evaluating the histopathological characters of pancreatic ductal adenocarcinoma (PDAC).MethodsThis retrospective study enrolled 50 patients with PDAC confirmed by pathology from December 2018 to May 2020. All patients underwent DWI and IVIM-DWI before surgeries. Patients were classified into low- and high-fibrosis groups. Apparent diffusion coefficient (ADC), diffusion coefficient (D), false diffusion coefficient (D*), and perfusion fraction (f) were measured by two radiologists, respectively in GE AW 4.7 post-processing station, wherein ADC values were derived by mono-exponential fits and f, D, D* values were derived by biexponential fits. The tumor tissue was stained with Sirius red, CD34, and CK19 to evaluate fibrosis, microvascular density (MVD), and tumor cell density. Furthermore, the correlation between ADC, D, D*, and f values and histopathological results was analyzed.ResultsThe D values were lower in the high-fibrosis group than in the low-fibrosis group, while the f values were opposite. Further, no statistically significant differences were detected in ADC and D* values between the high- and low-fibrosis groups. The AUC of D and f values had higher evaluation efficacy in the high- and low-fibrosis groups than ADC values. A significant negative correlation was established between D values, and fibrosis and a significant positive correlation were observed between f values and fibrosis. No statistical difference was detected between DWI/IVIM parameters values and MVD or tumor cell density except for the positive correlation between D* values and tumor cell density.ConclusionsD and f values derived from the IVIM model had higher sensitivity and diagnostic performance for grading fibrosis in PDAC compared to the conventional DWI model. IVIM-DWI may have the potential as an imaging biomarker for predicting the fibrosis grade of PDAC.

In species that are subject to brood parasitism, individuals often vary in their responses to parasitic eggs, with some rejecting the eggs while others do not. While some factors, such as host age (breeding experience), the degree of egg matching and the level of perceived risk of brood parasitism have been shown to influence host decisions, much of the variation remains unexplained. The host personality hypothesis suggests that personality traits of the host influence its response to parasitic eggs, but few studies have tested this. We investigated the relationship between two personality traits (exploration and neophobia) and a physiological trait (breathing rate) of the host, and egg-rejection behaviour in a population of Daurian redstarts Phoenicurus auroreus in northeast China. We first show that exploratory behaviour and the response to a novel object are repeatable for individual females and strongly covary, indicating distinct personality types. We then show that fast-exploring and less neophobic hosts were more likely to reject parasitic eggs than slow-exploring and more neophobic hosts. Variation in breathing rate—a measure of the stress-response—did not affect rejection behaviour. Our results demonstrate that host personality, along the bold-shy continuum, predicts the responses to parasitic eggs in Daurian redstarts, with bold hosts being more likely to reject parasitic eggs.

Rationale and Objectives The aim of this study was to use histogram analysis to assess the correlation between blood oxygen-level dependent magnetic resonance imaging (BOLD-MRI) and renal fibrosis induced by unilateral ureteral obstruction (UUO) in an animal model for a long experimental period. Materials and Methods The rabbits were randomly divided into a control group (n = 6) and a UUO group (n = 30). The rabbits in the UUO group underwent left ureteral obstruction surgery. BOLD-MRI examinations were performed at 2, 4, 6, and 8 weeks after ligation. After the examinations, nephrectomy was performed for histologic evaluation. Histogram analysis of the left renal cortex (C) R2* values was performed to measure the mean, median, 10th percentile, 90th percentile, skewness, and kurtosis for all kidneys. Masson trichrome staining was used to assess the percentage of fibrotic area. Results The histogram R2* values of the mean, median, 10th percentile, and 90th percentile at week 2 were all lower than those at baseline. Over the course of UUO progression, there were statistical differences between the histogram R2* values at any other two time points, except between weeks 4 and 6, and weeks 6 and 8. A close correlation was found between the percentage of fibrotic area and R2* values (mean: F = 21.49, p = 0.0001, R2 = 0.49, median: F = 30.07, p Conclusion BOLD-MRI could reflect the formation and progression of renal fibrosis in a rabbit UUO model; however, the value of BOLD-MRI in the long-term evaluation of fibrosis is limited.

Background Mild cognitive impairment (MCI) occurs frequently in many end stage renal disease (ESRD) patients, may significantly worsen survival odds and prognosis. However, the exact neuropathological mechanisms of MCI combined with ESRD are not fully clear. This study examined functional connectivity (FC) alterations of the default-mode network (DMN) in individuals with ESRD and MCI. Methods Twenty–four individuals with ESRD identified as MCI patients were included in this study; of these, 19 and 5 underwent hemodialysis (HD) and peritoneal dialysis (PD), respectively. Another group of 25 age-, sex- and education level-matched subjects were recruited as the control group. All participants underwent resting-state functional MRI and neuropsychological tests; the ESRD group underwent additional laboratory testing. Independent component analysis (ICA) was used for DMN characterization. With functional connectivity maps of the DMN derived individually, group comparison was performed with voxel-wise independent samples t-test, and connectivity changes were correlated with neuropsychological and clinical variables. Results Compared with the control group, significantly decreased functional connectivity of the DMN was observed in the posterior cingulate cortex (PCC) and precuneus (Pcu), as well as in the medial prefrontal cortex (MPFC) in the ESRD group. Functional connectivity reductions in the MPFC and PCC/Pcu were positively correlated with hemoglobin levels. In addition, functional connectivity reduction in the MPFC showed positive correlation with Montreal Cognitive Assessment (MoCA) score. Conclusion Decreased functional connectivity in the DMN may be associated with neuropathological mechanisms involved in ESRD and MCI.

The dynamic model of overhead crane is highly nonlinear and uncertain. In this paper, Takagi-Sugeno (T-S) fuzzy modeling and PSO-based robust linear quadratic regulator (LQR) are proposed for anti-swing and positioning control of the system. First, on the basis of sector nonlinear theory, the two T-S fuzzy models are established by using the virtual control variables and approximate method. Then, considering the uncertainty of the model, robust LQR controllers with parallel distributed compensation (PDC) structure are designed. The feedback gain matrices are obtained by transforming the stability and robustness of the system into linear matrix inequalities (LMIs) problem. In addition, particle swarm optimization (PSO) algorithm is used to overcome the blindness of LQR weight matrix selection in the design process. The proposed control methods are simple, feasible, and robust. Finally, the numeral simulations are carried out to prove the effectiveness of the methods.

BACKGROUND: Susceptibility weighted imaging (SWI) could reflect tissue blood oxygen levels, and then whether it could be used to evaluate renal injury remains to be further studied. This study aimed to examine the performance of SWI parameters and SWI-based texture features in evaluating renal dysfunction of type 2 diabetes mellitus (T2DM). METHODS: Forty-five patients with T2DM were included. With the estimated glomerular filtration rate (eGFR), the patients were divided into non-moderate-severe renal injured group (non-msRI, eGFR >60 mL/min/1.73 m(2)) and moderate-severe renal injured group (msRI, eGFR ≤60 mL/min/1.73 m(2)). The 3 SWI parameters and 16 SWI-based texture features between non-msRI and msRI were compared. The correlation between the parameters and BUN, Scr was analyzed. RESULTS: The signal intensity ratio of the medulla to psoas muscle (MPswi) was significantly lower than the signal intensity ratio of the cortex to psoas muscle (CPswi) in non-msRI and msRI group (t=8.619, 3.483, respectively, P0.05), and AUCs were 0.703–0.854. CMswi was an independent protective factor for msRI (OR =0.026, P=0.003). MPswi and CMswi were correlated with BUN (r=0.416, −0.545, P

To explore if RForty rabbits were randomly divided into 4 groups according to the clipping time: the sham group and 45 min, 60 min, and 75 min for the mild, moderate, and severe groups (with n = 10 each group), respectively. Intravenous furosemide (FU) was administered 24 h after IRI. All rabbits were performed 5 times (IRICompared to the baseline, the medullary RR

Background Calculation methods have a critical role in the precise sorting of medical images. Particle swarm optimization (PSO) is a widely used approach in the clinical centers and for other medical applications as it can disentangle optimization errors in attached spaces. In this work, a new model for image segmentation is proposed through an improved optimization algorithm. Methods A novel multi-objective algorithm was configured, named "multi-objective mathematical programming" (MOMP), based on the normalized normal constraint method (NNCM). In this model, the proposed algorithm was applied to evaluate the robustness of the suggested model through including the synthetic images of objects with various concavities and Gaussian noise. This model segments the individuals' heart and the left ventricle from data sets of sequentially evaluated tomography and magnetic resonance images. To objectively and quantifiably assess the presentation of the medical image segmentations based on regions outlined by experts and the graph cut method, a set of distance and resemblance metrics were implemented. Results The numerical results obtained in experimental test cases demonstrate the validity and superiority of the proposed model through better segmentation accuracy and stability. Conclusions The results indicated that the proposed MOMP method can outperform all traditional models in terms of segmentation accuracy and stability, and is thus appropriate for use in medical imaging.

Droplet generation in a T-junction with surfactants is simulated using our recently developed lattice Boltzmann method. The method is first used to explore the effect of surfactant concentration [Formula: see text] on droplet generation. As [Formula: see text] increases, droplet generation tends to shift from squeezing to dripping regime and then to jetting regime. In the clean system, the upstream pressure varies almost periodically with time. However, in the surfactant-laden system, the upstream pressure no longer varies periodically but overall increases with time for droplet generation in squeezing and dripping regimes. This is because the addition of surfactants results in an additional pressure drop between the front and rear of the generated droplet. Then, droplet generation in both clean and surfactant-laden systems is compared to explore the surfactant role under different values of the capillary number [Formula: see text]. In either clean or surfactant-laden system, the pressure upstream of the junction rapidly decreases as [Formula: see text] increases. In the presence of surfactants, the upstream pressure overall increases with time for droplet generation in squeezing and dripping regimes, but the increased amplitude decreases with [Formula: see text]. Finally, we establish the phase diagrams describing how the droplet generation regime varies with flow rate ratio and [Formula: see text] in both clean and surfactant-laden systems. It is found that the addition of surfactants reduces the critical capillary number distinguishing squeezing from dripping and the critical capillary number distinguishing dripping from jetting.

BACKGROUND End-stage renal disease (ESRD) patients often have cognitive dysfunction. The abnormal changes in the brains of ESRD patients are difficult to detect with routine imaging examination. Cognitive performance scales are also not an ideal tool because assessments using these scales can be subjective and might be difficult to administer in some ESRD patients. Functional magnetic resonance has the advantages of non-radiation, multidirectional imaging, good repeatability. Using resting-state functional magnetic resonance imaging (rs-fMRI) and an amplitude of low-frequency fluctuation (ALFF) algorithm, this study characterized spontaneous brain activity and explored its relationship with cognitive function in ESRD patients. The aim of this study was to provide objective functional imaging evidence to reveal the pathophysiological mechanism of cognitive dysfunction in ESRD patients. METHODS This study recruited 35 ESRD patients and 25 healthy controls (HC) who were matched to the ESRD group by age, sex, and years of education. All study subjects were examined by Montreal Cognitive Assessment (MoCA) and rs-fMRI. Data Processing & Analysis of Brain Imaging (DPABI) V4.3 software was used to preprocess the data to obtain ALFF maps. The ALFF value of the cingulate gyrus was compared between the ESRD and HC groups. Subsequently, the correlation between the ALFF value of the cingulate gyrus and the MoCA score was analyzed in ESRD patients. RESULTS Compared with the HC group, the ESRD group had a significantly lower MoCA score (P