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In this article, we investigate the horizontal trajectory tracking problem for an underactuated stratospheric airship subject to nonvanishing external disturbances and model uncertainties. By transforming the tracking errors into new virtual error variables, we can specify the transient and steady-state tracking performance of the resulting nonlinear system quantitatively, which means that under the proposed control scheme, the tracking errors will converge to prescribed residual sets around the origin before a preselected finite time with decay rates no less than a preassignable value. To address unknown items, minimal learning parameter (MLP) techniques for neural networks (NNs) approximation are employed, which efficaciously relax the computational burden, enhance the robustness against dynamics uncertainties and provide an improved property for disturbances rejection. A finite-time convergent observer (FTCO) is incorporated into the control framework to realise output-feedback control, ensuring that estimation errors are bounded during operation and approach zero within a finite time. Stability analysis proves that all the closed-loop signals are uniformly bounded. The effectiveness and advantages of the proposed control strategy are verified by simulation results.
A new developed spatially targeted mollusciciding technology for snail control was utilised in a research site. This study aims to analyse whether this technology can achieve rational effectiveness compared with the routine method. Snail density was monitored every spring and autumn from 2010 to 2017 at the research site and routine mollusciciding for snail control was then performed. After snail density monitoring in spring 2018, spatially targeted mollusciciding technology was adopted. Log-linear regression and nonlinear regression models were used for snail density prediction in autumn 2018 and the predicted value was compared with the actual snail density in autumn 2018 to verify the effectiveness of the spatially targeted mollusciciding. Monitoring results showed that overall snail density in the research site decreased from 2010 to 2018. The monitored snail density in autumn 2018 was 0.014/0.1 m2. Predicted by the log-linear regression model, the snail density in autumn 2018 would be 0.028 (95% CI 0.11–0.072)/0.1 m2. Predicted by the nonlinear regression model, the snail density growth in autumn 2018 in contrast to spring 2018 would be 79.79% (95% CI 54.81%–104.77%) and the actual value was 55.56%. Therefore, the effectiveness of the first application of spatially targeted mollusciciding was acceptable. However, the validation of its sustainable effectiveness still needs a replicated study comparing areas where targeted and untargeted methods are applied simultaneously and both snail abundance and human infection are monitored.
This study aimed to investigate the clinical characteristics and to analyse the epidemiological features of coronavirus disease 2019 (COVID-19) patients during convalescence. In this study, we enrolled 71 confirmed cases of COVID-19 who were discharged from hospital and transferred to isolation wards from 6 February to 26 March 2020. They were all employees of Zhongnan Hospital of Wuhan University or their family members of which three cases were <18 years of age. Clinical data were collected and analysed statistically. Forty-one cases (41/71, 57.7%) comprised medical faculty, young and middle-aged patients (aged ⩽60 years) accounted for 81.7% (58/71). The average isolation time period for all adult patients was 13.8 ± 6.1 days. During convalescence, RNA detection results of 35.2% patients (25/71) turned from negative to positive. The longest RNA reversed phase time was 7 days. In all, 52.9% of adult patients (36/68) had no obvious clinical symptoms, and the remaining ones had mild and non-specific clinical symptoms (e.g. cough, sputum, sore throat, disorders of the gastrointestinal tract etc.). Chest CT signs in 89.7% of adult patients (61/68) gradually improved, and in the others, the lesions were eventually absorbed and improved after short-term repeated progression. The main chest CT manifestations of adult patients were normal, GGO or fibre streak shadow, and six patients (8.8%) had extrapulmonary manifestations, but there was no significant correlation with RNA detection results (r = −0.008, P > 0.05). The drug treatment was mainly symptomatic support therapy, and antibiotics and antiviral drugs were ineffective. It is necessary to re-evaluate the isolation time and standard to terminate isolation for discharged COVID-19 patients.
The present study was designed to detect three single nucleotide polymorphisms (SNPs) located on 22q11 that was thought as being of particularly importance for genetic research into schizophrenia. We recruited a total of 176 Chinese family trios of Han descent, consisting of mothers, fathers and affected offspring with schizophrenia for the genetic analysis. The transmission disequilibrium test (TDT) showed that of three SNPs, rs10314 in the 3′-untranslated region of the CLDN5 locus was associated with schizophrenia (χ2 = 4.75, P = 0.029). The other two SNPs, rs1548359 present in the CDC45L locus centromeric of rs10314 and rs739371 in the 5′-flanking region of the CLDN5 locus, did not show such an association. The global chi-square (χ2) test showed that the 3-SNP haplotype system was not associated with schizophrenia although the 1-df test for individual haplotypes showed that the rs1548359(C)-rs10314(G)-rs739371(C) haplotype was excessively non-transmitted (χ2 = 5.32, P = 0.02). Because the claudin proteins are a major component for barrier-forming tight junctions that could play a crucial role in response to changing natural, physiological and pathological conditions, the CLDN5 association with schizophrenia may be an important clue leading to look into a meeting point of genetic and environmental factors.
To demonstrate whether the communication between two SD rats base on the similar genetic basis or the same living environment, who separated (including visual, auditory, tactile, olfactory and tasting inputs)from each other, occurs.
One SD rat (RECEIVER) was examined by EEG spectral analysis and ECG analysis under anesthesia while the other SD rat (SENDER) received optimal stimuli or malignant stimuli. The course was conducted in the shielded and the unshielded. Compare the EEG and ECG of RECEIVER between the stimulation state and resting state of SENDER.
This study show no significant difference in EEG (index: percentile weight and average weight of EEG on frontal lobe, temporal lobe, hippocampus of each frequency band) and ECG (index: R, PR segment, ST segment, QRS segment, QT segment) of RECEIVER during the time that the SENDER suffered from malignant stimulation, experienced optimal stimulation and of resting state.
The communication of SD rats, not through common five sense organ may not exist, even though the same genetic basis or the common living surrounding.The optimal stimuli and the malignant stimuli of SENDER cannot influence the EEG of Frontal lobe, temporal lobe, hippocampus and ECG on RECEIVER. There is no sufficient evidence for the existence of this communication of animal.
Post-stroke depression (PSD) is the most common psychiatric complication facing stroke survivors and has been associated with increased distress, physical disability, poor rehabilitation, and suicidal ideation. However, the pathophysiological mechanisms underlying PSD remain unknown, and no objective laboratory-based test is available to aid PSD diagnosis or monitor progression.
Here, an isobaric tags for relative and absolute quantitation (iTRAQ)-based quantitative proteomic approach was performed to identify differentially expressed proteins in plasma samples obtained from PSD, stroke, and healthy control subjects.
The significantly differentiated proteins were primarily involved in lipid metabolism and immunoregulation. Six proteins associated with these processes – apolipoprotein A-IV (ApoA-IV), apolipoprotein C-II (ApoC-II), C-reactive protein (CRP), gelsolin, haptoglobin, and leucine-rich alpha-2-glycoprotein (LRG) – were selected for Western blotting validation. ApoA-IV expression was significantly upregulated in PSD as compared to stroke subjects. ApoC-II, LRG, and CRP expression were significantly downregulated in both PSD and HC subjects relative to stroke subjects. Gelsolin and haptoglobin expression were significantly dysregulated across all three groups with the following expression profiles: gelsolin, healthy control > PSD > stroke subjects; haptoglobin, stroke > PSD > healthy control.
Early perturbation of lipid metabolism and immunoregulation may be involved in the pathophysiology of PSD. The combination of increased gelsolin levels accompanied by decreased haptoglobin levels shows promise as a plasma-based diagnostic biomarker panel for detecting increased PSD risk in post-stroke patients.
To demonstrate whether communication phenomenon of brain electrical activity, NOT through modalities including visual, auditory, tactile, olfactory and tasting inputs,related to emotional or cognitive content, between two adults individual (named as SENDER and RECEIVER) exists.
We applying high density ERP technique, using CAPS, letter pictures, CAFPS as stimuli⌧compare the information of ERP differences on RECEIVER at the same time the SENDER perform a standard categorization task which lead to significant difference in ERP.
We found ERP of SENDER show difference significantly in the s1 (neutral pictures), s2 (extremely negative pictures) and s3 (letter pictures), simultaneously, under the different stimuli of SENDER, the ERP of RECEIVER show that there is the significant difference in late potentials between s2 and s1, between s2 and s3 which may be much wider. There is no difference between happy face⌧sad face⌧angry face pictures in ERP of RECEIVER.
This finding support the communication between brain electrical activity of two separated subjects isolated from five sensory channels may happen, it may occur at the same time or delay, Cognitive and emotional experience may arouse electrical activity of different brain region, the detail of communication tend to affective content about self-experience.
To demonstrate whether communication phenomenon of brain electrical activity, NOT through conventional sense such as look⌧listen⌧touch⌧smell⌧taste⌧related to emotional or cognitive content, between two adults individual (named as SENDER and RECEIVER) exists.
Applying high density ERP technique, using CAPS⌧CAFPS as stimuli⌧compare the information of ERP differences on RECEIVER at the same time the SENDER perform a standard categorization task which lead to significant difference in ERP.
The ERP of SENDER show difference significantly in the s1 (neutral pictures), s2 (extremely negative pictures), simultaneously, under the different stimuli of SENDER, the ERP of RECEIVER show that there is the significant difference in late potentials between s2 and s1. There is no difference between happy face⌧sad face⌧angry face⌧pictures in ERP of RECEIVER.
The communication between brain electrical activity of two separated subjects isolated from five sensory channels may occur,it may occur at the same time or delay, Cognitive and emotional experience may arouse electrical activity of different brain region, the detail of communication tend to affective content about self - experience.
The catechol-O-methyltransferase (COMT) gene is related to dopamine degradation and has been suggested to be involved in the pathogenesis of major depressive disorder (MDD). However, how this gene affects brain function properties in MDD is still unclear.
Fifty patients with MDD and 35 cognitively normal participants underwent a resting-state functional magnetic resonance imaging scan. A voxelwise and data-drive global functional connectivity density (gFCD) analysis was used to investigate the main effects and the interactions of disease states and COMT rs4680 gene polymorphism on brain function.
We found significant group differences of the gFCD in bilateral fusiform area (FFA), post-central and pre-central cortex, left superior temporal gyrus (STG), rectal and superior temporal gyrus and right ventrolateral prefrontal cortex (vlPFC); abnormal gFCDs in left STG were positively correlated with severity of depression in MDD group. Significant disease × COMT interaction effects were found in the bilateral calcarine gyrus, right vlPFC, hippocampus and thalamus, and left SFG and FFA. Further post-hoc tests showed a nonlinear modulation effect of COMT on gFCD in the development of MDD. Interestingly, an inverted U-shaped modulation was found in the prefrontal cortex (control system) but U-shaped modulations were found in the hippocampus, thalamus and occipital cortex (processing system).
Our study demonstrated nonlinear modulation of the interaction between COMT and depression on brain function. These findings expand our understanding of the COMT effect underlying the pathophysiology of MDD.
Psychomotor retardation (PMR) in depression is analogous to the hypokinesia in Parkinson's disease, which is associated with the unbalanced direct and indirect pathways of cortico-basal ganglia-thalamo-cortical (CBTC) circuitry. This study hypothesized PMR in major depressive disorder (MDD) should be associated with the hyperactivity of CBTC indirect pathways.
To substantiate the hypothesis that the PMR symptom of MDD might attribute to the hyperactivity of the ortico-basal ganglia-thalamo-cortical indirect pathway which could inhibit psychomotor performance.
We investigated the intrinsic stiato-subthalamic nucleus (STN)-thalamic functional connectivity (FC), three pivotal hubs of the indirect pathway, in 30 MDD patients with PMR (PMR group) and well matched 30 patients without PMR (NPMR group) at baseline, and 11 patients of each group at follow-up who remitted after antidepressant treatment.
The results showed increased STN-striatum FC of PMR group at baseline and no more discrepancy at follow-up, and significant correlation between PMR severity and thalamo-STN FC.
Our findings suggested the increased STN- striatum FC should be considered as a state biomarker to distinguish MDD patients with PMR from patients without PMR at acute period, and thalamo-STN FC could be identified as the predictor of the PMR severity for MDD patients.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Feathers play a critical role in thermoregulation and directly influence poultry production. Poor feathering adversely affects living appearance and carcass quality, thus reducing profits. However, producers tend to ignore the importance of feather development and do not know the laws of feather growth and development. The objective of this study was to fit growth curves to describe the growth and development of feathers in yellow-feathered broilers during the embryonic and posthatching periods using different nonlinear functions (Gompertz, logistic and Bertalanffy). Feather mass and length were determined during the embryonic development and posthatching stages to identify which growth model most accurately described the feather growth pattern. The results showed that chick embryos began to grow feathers at approximately embryonic (E) day 10, and the feathers grew rapidly from E13 to E17. There was little change from E17 to the day of hatching (DOH). During the embryonic period, the Gompertz function (Y = 798.48e−203 431exp(−0.87t), Akaike’s information criterion (AIC) = −0.950 × 103, Bayesian information criterion (BIC) = −0.711 × 103 and mean square error (MSE) = 559.308) provided the best fit for the feather growth curve compared with the other two functions. After hatching, feather mass and length changed little from the DOH to day (D) 14, increased rapidly from D21 to D91 and then grew slowly after D91. The first stage of feather molting occurred from 2 to 3 weeks of age when the down feathers were mostly shed and replaced with juvenile feathers, and the second stage occurred at approximately 13 to 15 weeks of age. The three nonlinear functions could overall fit the feather growth curve well, but the Bertalanffy model (Y = 116.88 × (1−0.86e−0.02t)3, AIC = 1.065 × 105, BIC = 1.077 × 105 and MSE = 11.308) showed the highest degree of fit among the models. Therefore, the Gompertz model exhibited the best goodness of fit for the feather growth curve during the embryonic development, while the Bertalanffy model was the most suitable model due to its accurate ability to predict the growth and development of feathers during the growth period, which is an important commercial characteristic of yellow-feathered chickens.
The association between eosinophil count and cholelithiasis among people with Clonorchis sinensis infection is still uncertain. We conducted a cross-sectional study to investigate the associations among Clonorchis sinensis infection, eosinophil count and cholelithiasis. The study included 4628 participants from January to December 2018. The levels of eosinophil count were divided into four groups according to the quartiles of eosinophil count. Spearman's rank correlation was performed to assess the association between eosinophil counts and Clonorchis sinensis egg counts. Multiple regression analysis was performed to evaluate the relationships among C. sinensis infection, eosinophil count and cholelithiasis after adjusting for three models. The prevalence of C. sinensis infection was 38.72% (1792/4628), and the prevalence of cholelithiasis was 6.03% (279/4628). The infection rate of C. sinensis was higher in the cholelithiasis group than in the non-cholelithiasis group (63.08% vs. 37.16%, P < 0.001). Significant differences were found among various eosinophil count quartiles for C. sinensis infection, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), γ-glutamyltranspeptidase (γ-GT), triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), creatinine (CRE), blood urea nitrogen (BUN), uric acid (UA) and non-alcoholic fatty liver disease (NAFLD) (all P < 0.001). A significant positive correlation was found between eosinophil count and log-transformed C. sinensis egg count (r = 0.9477, P < 0.001). Multiple logistic regression analysis revealed that light and moderate intensities of C. sinensis infection were associated with cholelithiasis (P < 0.01 and P < 0.001, respectively), and C. sinensis infection with eosinophil count ranging from 0.05 to 0.5 × 109/l were associated with cholelithiasis (P < 0.05). In conclusion, our findings suggest that the light and moderate infections of C. sinensis with eosinophil count ranging from 0.05 to 0.5 × 109/l may be associated with a higher risk of cholelithiasis.
To examine the relationship between the therapeutic effect of intratympanic methylprednisolone perfusion and histone acetylation in refractory sudden sensorineural hearing loss.
Thirty-four refractory sudden sensorineural hearing loss patients were enrolled and treated with intratympanic methylprednisolone perfusion. Pure tone average, acetylated histone H3, acetylated histone H4 and histone deacetylase 2 (HDAC2) were measured in peripheral blood mononuclear cells before and after intratympanic methylprednisolone perfusion. Sixteen healthy volunteers were recruited to obtain normal reference values.
Pure tone average in sudden sensorineural hearing loss patients improved from 84.14 ± 13.54 dB to 73.56 ± 18.45 dB after intratympanic methylprednisolone perfusion. Up-regulations in HDAC2 protein level, and down-regulations in histone H3 and H4 acetylation were observed in the intratympanic methylprednisolone perfusion sensitive group (pure tone average gain of 15 dB or more), while no significant changes were observed in the intratympanic methylprednisolone perfusion insensitive group (pure tone average gain of less than 15 dB).
Intratympanic methylprednisolone perfusion can improve hearing in a considerable number of refractory sudden sensorineural hearing loss patients. The therapeutic effect is closely related to reduced histone acetylation.
Staphylococcus aureus has been recognised as one of the important zoonotic pathogens. However, knowledge about the epidemiology and genetic characteristics of S. aureus in rabbits was limited. The aim of this study was to determine the characteristics of 281 S. aureus isolated from dead rabbits of nine rabbit farms in Fujian Province, China. All the isolates were characterised by multi-locus sequencing typing, detection of virulence factors and antimicrobial susceptibility test. The results showed that the 281 isolates were grouped into two sequence types, ST121 (13.52%, 38/281) and ST398 (86.48%, 243/281). Surprisingly, the ST121 strains were only recovered from the lung samples from one of the nine rabbit farms studied. In the 281 isolates, the virulence genes of nuc, hla, hlb, clfA, clfB and fnbpA were positive, whereas the sea, seb, tsst, eta and etb genes were negative. Notably, the 38 ST121 isolates carried the pvl gene. All the 281 isolates were methicillin-susceptible S. aureus, and the isolates were susceptible to most of the used antibiotics, except for streptomycin, kanamycin, azithromycin and penicillin, and the resistance rates of which were 23.84%, 19.57%, 16.01% and 11.03%, respectively. This study first described the epidemiology and characteristics of S. aureus in rabbits in Fujian Province, which will help in tracking the evolution of epidemic strains and preventing the rabbit–human transmission events.
Two-dimensional particle-in-cell (PIC) simulations have been used to investigate the interaction between a laser pulse and a foil exposed to an external strong longitudinal magnetic field. Compared with that in the absence of the external magnetic field, the divergence of proton with the magnetic field in radiation pressure acceleration (RPA) regimes has improved remarkably due to the restriction of the electron transverse expansion. During the RPA process, the foil develops into a typical bubble-like shape resulting from the combined action of transversal ponderomotive force and instabilities. However, the foil prefers to be in a cone-like shape by using the magnetic field. The dependence of proton divergence on the strength of magnetic field has been studied, and an optimal magnetic field of nearly 60 kT is achieved in these simulations.
A multi-scale strategy is employed in the paper to investigate the thermo-mechanical properties of 2.5D angle-interlock woven shape memory polymer composites (SMPCs). In the study, the mesoscopic model of 2.5D woven SMPCs and microscopic model of yarns are firstly developed. After that, the themo-viscoelastic constitutive relationship of the yarn is described in the form of hereditary integral and the parameters of relaxation moduli are obtained from nonlinear fitting of Prony series based on the results of finite element method (FEM). Based on the multi-scale models and the constitutive relationship, the effects of warp and weft arranged densities on viscoelastic properties of 2.5D woven SMPCs are studied in detail. Finally, the shape memory behavior along the warp direction in small strain region is also analyzed. The research in the paper lays a foundation for design and application of woven SMPCs in engineering.
This paper aims to build the finite element model of the composite sinusoidal specimens and to carry out the parametric analysis. In this paper, the damage behaviour and the energy-absorbing results of composite sinusoidal specimens have been studied by quasi-static crushing experiments. The failure mechanisms of specimens under quasi-static crushing is further analysed. A numerical simulation has been performed by using the finite element model code LS-DYNA. The numerical results, in terms of load -displacement data, have been compared against experimental data, and good agreement has been found. Moreover, a sensitivity study has been carried out by varying material properties in order to assess their influence on the numerical results, and the material parameter selection scheme is optimised based on the constructed corresponding response surfaces. The results show that the response surface model has passed the test of goodness of fit, and the optimisation method can effectively assist the finite element modelling, and greatly decrease the numbers of trial and error.