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A novel proposed approach of the recursive expectation–maximization (REM)–convex optimization algorithm is developed to solve the parameter identification problem of the Markov jump autoregressive exogenous (MJARX) systems with unknown time delays. First, the REM algorithm is employed for identifying the unknown time delay of the system, based on which the time-delay sequence is obtained. Subsequently, the model parameter vector is determined by the convex optimization algorithm. Finally, the transition probability matrix and variance are calculated based on the minimized mean square error. A numerical example and simulated continuous fermentation reactor process are implemented to demonstrate the effectiveness of the proposed algorithm. The identification results are better than the expectation–maximization algorithm and REM algorithm results.

There are few studies on esophageal adenosquamous carcinoma (ADSC). Our study intended to investigate the clinical and survival features of ADSC. We included esophageal cancer (EC) data from the Surveillance, Epidemiology, and End Results program database to explore clinical and survival traits. Propensity score matching (PSM), the multivariate Cox regression model, and survival curves were used in this study. A total of 137 patients with ADSC were included in our analysis. The proportion of ADSC within the EC cohort declined from 2004 to 2018. Besides, results indicated no significant difference in survival between ADSC and SCC groups (PSM-adjusted HR = 1.249, P = 0.127). However, the survival rate of the ADSC group was significantly worse than that of the ADC group (PSM-adjusted HR = 1.497, P = 0.007). For the ADSC group, combined treatment with surgery had a higher survival rate than other treatment methods (all P < 0.001). Surgical resection, radiotherapy, and chemotherapy were independent protective prognostic factors (all P < 0.05). The proportion of ADSC has been declining from 2004 to 2018. The prognosis of ADSC is not significantly different from that of SCC but is worse than that of ADC. Surgery, radiotherapy, and chemotherapy could improve the prognosis of patients. Comprehensive treatment with surgery as the main treatment is more beneficial for some patients.

Water temperature is the major ecophysiological factor for fish survival in nature and aquaculture. Compared with many homeotherms, fish can survive prolonged periods under the condition of low temperature. However, the metabolic strategies of the liver under a cold environment are still unknown in this species. In our present study, adult zebrafish were exposed to a cold or cold plus starvation environment to analyse the morphological characteristics of hepatocytes by light microscopy and transmission electron microscopy (TEM). The fish livers were dissected and observed under a microscope, and the liver size and shape appeared normal in all groups. Periodic acid-Schiff and TEM analysis showed that hepatic glycogen was significantly lower in zebrafish exposed to cold acclimation (CF group) than that zebrafish at the control water temperature (CT group). Moreover, qPCR and IHC results indicated that the expression of PYGL (a key enzyme involved in glycogenolysis) markedly increased in the CF group. After cold plus starvation treatment (CS group), autophagy activity was significantly enhanced and numerous mitophagic vacuoles were present in the cytoplasm of hepatocytes. In conclusion, hepatic glycogen was first mobilizing to supply energy, and then autophagy, especially mitophagy, played vital roles during nutrient deprivation in fish species.

Moral hazard have a non-negligible impact on supply chain sustainability, especially from a long-term perspective. This influence is more complicated in a dual-channel supply chain with free riding. Therefore, it is necessary to explore how manufacturers design multi-period incentive strategies in a dual-channel supply chain to deal with moral hazard problems from retailers. In this study, we built a game theory model that contains a retailer (she) who is delegated by a manufacturer (he) to sell products in her offline and online channels and to provide experience services in a physical store. The retailer has the option of exerting effort when providing experience services to boost demand. We explored and compared the manufacturer’s strategies that cover a time horizon of multiple periods under two circumstances: full information and repeated moral hazard. The following conclusions were drawn from this study. In the repeated moral hazard game, the incentive constraints of the retailer are only related to her current and the next-period profits and independent from the profits in other periods. Moreover, the incentive strategies in each period are affected by the historical information in the previous period, while the strategies under information symmetry are not affected by history. Specially, the manufacturer can induce effort by charging an up-front payment from the retailer in the previous period and then returning a utility based on the achieved demand. Therefore, the manufacturer can postpone the payment of incentive costs and shift the risk to the next period. Furthermore, the manufacturer’s incentive strategies are also affected by the free-riding effect between channels. That is, compared with the low-state transfer payment, the high-state transfer payment was found to be more sensitive to free riding.

The Category Switching Test (CaST) is a verbal fluency test with active semantic category switching. This study aimed to explore the association between CaST performance and brain amyloid-β (Aβ) burden in patients with mild cognitive impairment (MCI) and the neurofunctional mechanisms. A total of 112 participants with MCI underwent Florbetapir positron emission tomography, resting-state functional magnetic resonance imaging, and a neuropsychological test battery. The high Aβ burden group had worse CaST performance than the low-burden group. CaST score and left middle temporal gyrus fractional amplitude of low-frequency fluctuations (fALFF) related inversely to the global Florbetapir standardized uptake value rate. Functional connectivity between the left middle temporal gyrus and frontal lobe decreased widely and correlated with CaST score in the high Aβ burden group. Thus, CaST score and left middle temporal gyrus fALFF were valuable in discriminating high Aβ burden. CaST might be useful in screening for MCI with high Aβ burden.

The Trail Making Test (TMT) is a popular neuropsychological test derived from the Army Individual Test Battery, which was used by the U.S. Army. Its content was obviously designed within the English cultural context. Consequently, there is ongoing debate regarding TMT's applicability on non-English speaking population. The objective of this study was to selectively review the major variants of TMT that had been created to address this issue, including color trail test (CTT), shape trail test (STT), and language-specific versions of TMT. Meanwhile, functional magnetic resonance imaging (fMRI) can be conducted along with TMT to clarify the brain activity underlying TMT performance. This review drew conclusions on the clinical utility of these TMT variants. All research articles reviewed were published in English-language, peer-reviewed journals.

Tight integration of Global Navigation Satellite System (GNSS) and Ultra-Wide Band (UWB) is growing popularity as a positioning strategy relying on mass-market devices for applications dealing with localisation and tracking of agents in challenging environments. However, due to independent clocks of Commercial off-the-shelf (COTS) devices, the offset between the time-scales with respect to which measurements are time tagged must be mitigated to achieve accurate state-estimation via centralised, recursive filtering architectures. In this paper, it is analysed a GNSS/UWB Tightly-Coupled (TC) scheme based on an Extended Kalman Filter (EKF), and the integration of asynchronous GNSS/UWB measurements is investigated to highlight how it can induce state-estimation errors under different receiver kinematics. GNSS/UWB time calibration is addressed as a filtering problem, for which an EKF-based framework is developed to recursively model the GNSS/UWB time-offset as a further unknown in the system state-space model. Moreover, a double-update filtering model is proposed with embedded optimisations for the adaptive tuning of UWB ranging statistics. Experimental results with simulated data show that the double-update EKF algorithm can achieve a horizontal positioning accuracy gain 41.60 % over a plain EKF integration with uncalibrated time-offset and of 15.43 % over the EKF with naive time-offset calibration.

The cell wall mechanical properties are an important indicator for evaluating the overall mechanical properties of natural bamboo fibers. Using the nanoindentation technique, the variation of the mechanical properties of the fiber cell wall of Bambusa pervariabilis culms with different ages and different positions (both radial and longitudinal) was studied. Moreover, x-ray diffraction (XRD) was employed to measure the microfibril angle (MFA), and the correlation between the MFA and the mechanical properties of the fiber cell wall. The results showed that there was a remarkable difference in the fiber cell wall mechanical properties at different ages and at different radial and longitudinal positions. However, at different ages and at different positions, the absolute value of variation of MFA was less than 1° and was very minor. Furthermore, there was no significant correlation between the fiber cell wall mechanics and MFA, indicating that the mechanical property of the fiber cell walls might be synergistically affected by many factors.

A number of previous studies use auditor propensity to issue a going concern opinion (GCO) as a proxy of audit quality when examining a sample of financially distressed firms. This study examines whether audit quality (measured by discretionary accruals) influences the probability of financially distressed firms receiving GCOs using a non‐specific sample of 2937 firm‐year observations from Australia over the period 2011–2015. The study first investigates the association between financially distressed firms and the issuance of GCOs. This association is then re‐tested after separating the total sample into low and high audit quality subsamples. The results indicate that financially distressed firms are more likely to receive GCOs, confirming the application of ASA 570 Going Concern. However, financially distressed firms that receive GCOs from their auditors are limited to firms that have higher‐quality audits.

The anatomical characteristics of culms in Bambusa pervariabilis bamboo at different ages and heights were investigated by microscopy and image analysis. Among the two vascular bundle types found in culms, the broken-waist type was considered typical, with the following measurements: average proportion of fibrous tissue, 41.53 percent; length, 1.75 mm; slenderness ratio, 117; and Runkel ratio, 4.00. These values were close to those of the moso bamboo (Phyllostachys edulis), which is commercially relevant in China. Age and height significantly influenced the anatomical characteristics of B. pervariabilis: with an increase in age, both the length and double-wall thickness of the fiber gradually increased, whereas its lumen diameter decreased. The width of vascular bundles and the length, width, double-wall thickness, and lumen diameter of fiber markedly decreased from the bottom to the top. Therefore, B. pervariabilis is an ideal raw material for pulping and papermaking, and its performance is close to that of moso bamboo.

Fruit weight is an integral part of fruit quality and directly influences the commodity value and economic return of fruit crops. Despite the importance of fruit weight, its underlying molecular mechanisms remain understudied, especially for perennial fruit tree crops such as cultivated loquat (Eriobotrya japonica Lindl.). Auxin is known to regulate fruit development, but its role and metabolism during the development of loquat fruit remain obscure. In this study, we used a multi-omics approach, integrating whole-genome resequencing-based quantitative trait locus (QTL) mapping with an F1 population, population genomics analysis using germplasm accessions, transcriptome analysis, and metabolic profiling to identify genomic regions potentially associated with fruit weight in loquat. We identified three major loci associated with fruit weight, supported by both QTL mapping and comparative genomic analysis between small- and large-fruited loquat cultivars. Comparison between two genotypes with contrasting fruit weight performance by transcriptomic and metabolic profiling revealed an important role for auxin in the regulation of fruit development, especially at the fruit enlargement stage. The multi-omics approach identified homologs of ETHYLENE INSENSITIVE 4 (EjEIN4) and TORNADO 1 (EjTRN1) as promising candidates for the control of fruit weight. Three single nucleotide polymorphism (SNP) markers were also closely associated with fruit weight. Results from this study provide insights into the genetic and metabolic controls of fruit weight in loquat from multiple perspectives. The candidate genomic regions, genes, and sequence variants will facilitate our understanding of the molecular basis of fruit weight and lay a foundation for future breeding and manipulation of fruit weight in loquat.

With the rapid development of the aviation industry, the utilization rate of a runway is getting higher and higher, and the time that aircrafts use the runway for takeoff and landing is getting less and less. Accidents are prone to occur at this stage, so the wheel brake system that plays a key role at this stage attracts much attention. The safety of the wheel brake system is important to ensure the normal takeoff and landing of aircrafts, minimize the occurrence of brake accidents and ensure the safety of the occupants and aircrafts. However, domestic research on wheel brake system mostly focuses on system design and performance simulation. There is little research on condition monitoring and health assessment of wheel brake system, especially hydraulic brake system. Therefore, based on the analysis of the working principle and flight recording parameters of the wheel brake system, the hysteresis characteristics of the system are found for the first time. The model of the wheel brake system considering the hysteresis characteristics is constructed, a health monitoring method based on Kalman filter is established. The effectiveness of the proposed method is verified by simulation and flight record data.

Aircraft hydraulic system is an important system responsible for capacity transmission, which has a great impact on the safety of aircraft flight mission. Therefore, it is imperative to study the health monitoring and prediction of aircraft hydraulic system and its user systems. In this paper, the hydraulic system and its user systems of a certain type of domestic aircraft are taken as the research object. On the basis of analyzing its working principle and using relevant flight parameters, a health monitoring method of hydraulic system and its user systems based on BP neural network and Support Vector Machine (SVM) algorithm is proposed, thus the health monitoring of the hydraulic system and its user systems of aircraft is realized. Based on health monitoring, Logistic Regression (LR) model and Support Vector Machine Regression (SVR) algorithm are used to predict the change trend of aircraft health mechanism and health state, then the health prediction of aircraft hydraulics and its user systems is realized.

During the past decades, the number of rural–urban migrants has dramatically increased in China. Their well-being is important for social development and has attracted the attention of researchers. This paper adopts five waves of repeated cross-sectional datasets within a nine-year span, included in the Chinese General Social Survey (CGSS 2010–2018), to evaluate the impacts and mechanisms of internet adoption on the health status and subjective well-being of rural–urban migrants. Empirical results suggest that there are significant positive correlations between internet adoption and health status as well as subjective well-being. The results of structural equation modeling suggest that the impact of the internet on well-being occurs through increasing, bridging, and bonding social capital for rural–urban migrants. The mediating impact of bonding social capital on subjective well-being is more prominent, while the mediating impact of bridging social capital on health is stronger. Furthermore, we have explored the heterogeneous effects across gender and education. This is an early study which investigates such an important topic in the context of the digital era.

This paper studies the resilience of logistics network against node failures in the context of express industry owing to disruption in the network. By considering the flow capacity between the nodes and the impact of each node's failure, we propose a load redistribution mechanism in the presence of cascading failures which is akin to a criticality-based resilience assessment or stress testing the supply chain. To further investigate the impact of the node/nodes failure, we simulate and propose algorithms for two cascading failure scenarios, illustrating the different adjustment schemes for resilience improving strategies. A sensitivity analysis with managerial insights is also performed to investigate the effect of the adjustment schemes on the criticality of the nodes and the resilience of the express logistics network.