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The airborne Distributed Position and Orientation System (DPOS) is an important means for multi-point motion measurement required for earth observation with multi-task sensing loads. The sub-nodes in DPOS rely on the main node to perform transfer alignment for them to get high-precision motion data, which requires accurate deformation data and the relative motion relationship between different nodes. Fiber Bragg Grating (FBG) is one of the main means of deformation measurement at present. However, the time synchronization error between FBG and DPOS directly restricts the accuracy of transfer alignment. For this, a high-precision time synchronization method based on waveform matching is presented. Firstly, the data correlation between FBG and DPOS is analyzed. Then the main time error factors, sampling frequency and time delay are determined. On this basis, the empirical mode decomposition and wavelet analysis are used to extract and match the vibration data from the FBGS and bending angle data calculated by DPOS, thus updating the time-varying sampling frequency and time delay of FBGS, and finally achieving high-precision time synchronization between FBGS and DPOS. Results of ground dynamic experiment show that the standard deviation and mean value of FBG time error is less than 4ms and 2ms respectively, and the deformation displacement error of synchronized FBG data is less than 1%, which provides a prerequisite for high-precision transfer alignment of DPOS.

In Position and Orientation System (POS), the Global Navigation Satellite System (GNSS) is susceptible to external severe weather and electromagnetic interference, which will cause the sudden or abnormal measurement noise of the GNSS and reduce the integration accuracy and stability of POS. To solve this problem, this paper proposes an adaptive center differential Kalman filter (CDKF) based on gradient descent with momentum (named as GDM-ACDKF). Firstly, the iterative theory of measurement noise covariance is introduced into CDKF, and the adaptive CDKF based on fixed sliding window factor (ACDKF) is achieved to adjust the measurement noise covariance matrix adaptively. Then, to further improve the tracking measurement noise ability of ACDKF, motivated by the idea of momentum gradient descent, the function between estimated error variance matrix and sliding window factor is established and the adaptive sliding window based on gradient descent with momentum is derived, so that the adaptive sliding window factor can be obtained with the minimum estimated error variance matrix. The adaptive sliding window factor, served as a variable weighting factor for adjusting the measurement noise covariance matrix, can determine the update difference of the measurement noise covariance matrix at the current moment by adjusting the proportion of the current innovation in the mean innovation in a real time, so as to realize the prediction and tracking effect of the measurement noise. The flight test results show that the proposed method has stronger measurement noise tracking ability and higher precision compared with CDKF, strong tracking CDKF and ACDKF.

The layout of the airborne distributed position and orientation system (POS) directly affects the overall accuracy of the motion parameters of all load points obtained by the distributed POS. However, there are restrictions of space, weight and cost of the distributed POS, it is unrealistic to install an inertial measurement unit (IMU) at the location of each load. To solve this problem, based on modal analysis of wing structure, considering the two factors of the modal spatial intersection angle and the vibration amplitude, a novel fitness function model based on modal assurance criterion (MAC) and Gramian matrix criterion (GMC) is proposed to evaluate the population in the optimization algorithm. The hybrid adaptive particle swarm optimization and genetic algorithm (HAPSOGA) based on this proposed model is applied to the multiple system layout of airborne distributed POS to obtain the optimal layout scheme. The results of semi-physical simulation and ground verification experiment show that compared with the optimal method based on MAC, the optimal layout scheme determined by the proposed method can use less IMU and obtain higher overall accuracy of motion parameters for the remote sensing loads.

Distributed Position and Orientation System (POS) is a key equipment which can precisely measure multi-node time-spatial motion information for the high-resolution imaging of novel airborne remote sensing systems. The deformation of the lever-arm with irregular cross-section will seriously affect the transfer alignment accuracy of distributed POS. The existing Ko method can measure the deformation of most lever-arms, but it is not applicable to the lever-arm with irregular cross-section and cannot measure the axial displacement which is an important parameter of distributed POS. In order to solve this problem, a six-dimensional deformation measurement method of distributed POS based on Fiber Bragg grating (FBG) sensors is proposed. Firstly, a strain decoupling approach is presented to improve the strain measurement accuracy of the lever-arm with irregular cross-section. Secondly, an axial displacement model is established to further realize six-dimensional deformation measurement. The high precision six-dimensional deformation can be used for transfer alignment to improve the motion information measurement accuracy of distributed POS. Experimental results show the proposed method can measure the six-dimensional deformation with a higher accuracy compared to the existing Ko method.

Background The response rate and survival benefit of immunotherapy vary among patients, implying specific immune status of an individual could be associated with the effect of immunotherapy. However, in-depth studies of immune subtypes (ISs), immune landscape and tumour microenvironment of oesophageal cancer (ESCA) and their clinical implications are less reported. Methods We first accessed data from publicly available databases and preprocessed it based on a standard protocol. Then, ISs were identified by unsupervised learning. Thereafter, the association of these ISs and tumour mutation burden (TMB), biomarkers of chemotherapy-induced immune response, tumour markers were also assessed. In addition, the immune characteristics, immune landscape, co-expression network of immune genes, and clinical implications were visualized and analysed. Results We identified three immunoclusters based on immune-associated genes with intra-class heterogeneity and prognostic value. Cluster-specific associations with TMB, markers of chemotherapy-induced immune response, and tumour markers were revealed. A 4-gene signature (risk score= −0.16514291×BHLHE22−0.03964046×MXRA8−0.15242778×SLIT2−0.05553572×SPON1) based on co-expressed genes in the immunoclusters was developed and externally validated. Conclusions In summary, we identified clinically relevant immunoclusters in both adenocarcinoma and squamous cell carcinoma of oesophagus, revealing the necessity of assessing the complexity and diversity of immune microenvironment for cancer immunotherapy.

Tetrodotoxin (TTX) is a deadly neurotoxin and usually accumulates in large amounts in the ovaries but is non-toxic or low toxic in the testis of pufferfish. The molecular mechanism underlying sexual dimorphism of TTX accumulation in gonads is complex and unclear. Piwi/piRNA complexes are essential for germline specification, gametogenesis, and gonadal development, they also demonstrate sexual dimorphism in teleosts. Hence, the present study investigated the expression of piRNAs and mRNAs by transcriptomics in cultured pufferfish Takifugu flavidus after intramuscular administration of exogenous TTX. The results showed 80 piRNAs were down-regulated and 223 genes were up-regulated in the ovary after TTX administration. By contrast, 286 piRNAs were down-regulated and 445 genes were up-regulated after TTX administration in testis. Functional and pathway analyses indicated that the TTX up-regulated genes were enriched in the Wnt, ErbB and GnRH signaling pathways in ovary, while were enriched in the oocyte meiosis, estrogenesis biosynthesis and cell apoptosis-related pathways in testis. Interestingly, these genes were also the potential target genes of TTX downregulated piRNAs. Amhr2 and cyp19a were also identified as sex-related genes, involved in TTX administration. These results showed a certain level of consistency with the enrichment pathway analysis, which indicated that the TTX could affect the expression of sex-related genes, and work as an inhibitor for the testicular meiosis, but as a promoting factor for ovary development through piRNAs in pufferfish. In addition, TUNEL staining showed that significant apoptosis was detected in the TTX treated testis, and the role of the cell apoptotic pathway was further confirmed. Overall, this research will contribute to an understanding of the piwi function in TTX sexual dimorphism accumulation in pufferfish and provide a basis for further studies.

Tetrodotoxin (TTX) is a deadly neurotoxin and usually accumulates in large amounts in the ovaries but is non-toxic or low toxic in the testis of pufferfish. The molecular mechanism underlying sexual dimorphism accumulation of TTX in ovary and testis, and the relationship between TTX accumulation with sex related genes expression remain largely unknown. The present study investigated the effects of exogenous TTX treatment on Takifugu flavidus. The results demonstrated that exogenous TTX administration significantly incresed level of TTX concentration in kidney, cholecyst, skin, liver, heart, muscle, ovary and testis of the treatment group (TG) than that of the control group (CG). Transcriptome sequencing and analysis were performed to study differential expression profiles of mRNA and piRNA after TTX administration of the ovary and testis. The results showed that compared with female control group (FCG) and male control group (MCG), TTX administration resulted in 80 and 23 piRNAs, 126 and 223 genes up and down regulated expression in female TTX-treated group (FTG), meanwhile, 286 and 223 piRNAs, 2 and 443 genes up and down regulated expression in male TTX-treated group (MTG). The female dominant genes cyp19a1, gdf9 and foxl2 were found to be up-regulated in MTG. The cyp19a1, whose corresponding target piRNA uniq_554482 was identified as down-regulated in the MTG, indicating the gene expression feminization in testis after exogenous TTX administration. The KEGG enrichment analysis revealed that differentially expressed genes (DEGs) and piRNAs (DEpiRNAs) in MTG vs MCG group were more enriched in metabolism pathways, indicating that the testis produced more metabolic pathways in response to exogenous TTX, which might be a reason for the sexual dimorphism of TTX distribution in gonads. In addition, TdT-mediated dUTP-biotin nick end labeling staining showed that significant apoptosis was detected in the MTG testis, and the role of the cell apoptotic pathways was further confirmed. Overall, our research revealed that the response of the ovary and testis to TTX administration was largely different, the ovary is more tolerant whereas the testis is more sensitive to TTX. These data will deepen our understanding on the accumulation of TTX sexual dimorphism in Takifugu.

With the continuous improvement of the operation line network of urban rail transit, analyzing influencing factors of transfer passenger flow of urban rail transit is critical to improve the transfer demand analysis of urban rail transit. Using data collected from questionnaires, transfer passenger flow surveys and smart cards, this study proposes an approach base on nested logit passenger flow assignment model considering transfer choice behaviours of passengers. The transfer passenger flow at seven transfer stations in Nanjing is obtained. Subsequently, this study investigates the potential influencing factors of transfer passenger flow, including the node degree, geographic location (located in the city center, urban fringe, suburbs or suburban fringe), economic location (distance from the city center) and transportation locations (if it is close to a transportation hub or in combination with the hub) of rail transit transfer stations. The results indicate that a positive correlation between the transfer passenger flow and the node degrees of transfer stations. However, the relationship between transfer passenger flow and the economic, geographic, and transportation locations of transfer stations is not clear. The finding have reference value for the network design of rail transit transfer stations and transfer facilities, and provide reference for the analysis of passenger flow under network operation.

We study the effects of monetary policy in an economy with distortions. Between 2006 and 2019, China’s central bank frequently adjusted required reserve ratios (RR) and interest rates (IR) to implement monetary policy. We examine how stock prices react to these adjustments and distinguish between state-owned-enterprises (SOEs) and private-owned-enterprises (POEs). We find that SOEs benefit disproportionately more from expansionary monetary policy than POEs, especially via interest rate cuts. In contrast, POEs benefit greatly from contractionary monetary policy via interest rate hikes. These findings shed light on the monetary transmission mechanisms in a market with interest rate control and credit rationing.

Precision medicine has been getting more attention in lung cancer treatment. Here, we report an unusual case of a 71-year-old Chinese male patient with poorly differentiated lung adenocarcinoma with lymph node metastasis. A 5 years' treatment history of this patient is reported. By serial genetic tests of circulating tumor DNA (ctDNA) from peripheral blood and sediment cell genomic DNA (PE-sDNA) from pleural effusion, a novel chronological combination treatment of icotinib, osimertinib, and crizotinib was adopted for the present genetic mutations, including EGFR exon 19 deletion, EGFR p.T790M, and MET amplification.

Airborne earth observation with multiple imaging sensors requires high-precision motion information of multiple nodes on aircraft wings. Distributed position and orientation system (DPOS) is an important way to meet this acquirement, in which the high-precision motion parameters of sub-nodes are calculated by transfer alignment. Due to the complex elastic deformation between the nodes and the different accuracy of deformation data, the transfer alignment accuracy of each sub-node is inconsistent. Focus on this problem, a novel deformation measurement method based on accelerometer and an innovative distributed filter are proposed. Firstly, the wing deformation is calculated by relationship of the acceleration between master node and sub-node. The deformation data includes bending angle and deflection. Then a novel distributed filter is conducted, which includes three parts. The first part is to determine the relation model of motion information between different nodes. This relation model is calculated based on the above deformation data. The second part is sensor-level inertial measurement fusion, which can use the accelerometer data with small bias to amend gyroscope data with serious drift and improve sensor data precision of all nodes. The third part is system-level navigation data fusion, which fuses the navigation data of all nodes and improve the motion information precision of all nodes. The dynamic vibration experiments show that the proposed deformation measurement method can achieve better measurement accuracy than fiber brag grating sensor, in which the deflection error is reduced by 20%, and the standard deviation of bending angle error is reduced by 55%. Based on the above deformation data, the innovative distributed filter can further reduce the position error obviously. Especially, the height error can be decreased by over 36%.

Distributed array antenna synthetic aperture radar (SAR), flexible baseline interferometric SAR (InSAR) or integrated multi-task imaging sensors are the most attractive development directions of aerial survey and remote sensing system, and urgently demand a distributed Position and Orientation System (DPOS) to accurately measure multi-nodes time-spatial reference information. However, the traditional transfer alignment (TA) method can't meet the requirements of some high precision interferometric imaging task. To solve the problem, a dual-filter TA method based on position-velocity-attitude matching (PVAM) was proposed. Firstly, the TA method based on attitude matching (AM) is conducted in filter-1 to estimate the flexible angles and the derivatives. Then the TA method based on position-velocity matching (PVM) is conducted in filter-2, and the position and velocity measurements are compensated by the flexible angles and the derivatives estimated by filter-1. Finally, the strapdown solutions of slave IMU are corrected by the corrections from both filter-1 and filter-2. A semi-physical simulation based on airborne DPOS flight experiment has been conducted, verifying that the baseline error has been reduced from 0.0240 m to 0.0083 m and the computation time has been decrease by 3.41%.

Transfers between urban rail transit (URT) and its feeder modes represent a considerable barrier to its ridership and the network-wide usage of public transit. The aim of this research is to quantify the time-independent transfer penalty between URT system and feeder modes and to explore its variability by different factors. Based on Melbourne URT origin and destination survey data, this study focused on URT access and egress journeys and estimated URT feeder transfer penalties by formulating feeder mode choice models. With three-hourly weather data and demographical data introduced, this paper conducted disaggregate analyses to investigate the variability of URT feeder transfer penalty across weather conditions, trip types and individual characteristics. According to the model estimation results, the values of transfer penalty vary according to the direction of transfer and the preference ordering for different transfer combinations is URT-tram, URT-bus, tram-URT, bus-URT and auto-URT. It found that local weather elements in terms of air temperature and precipitation are significant factors resulting in the variability of the transfer perception by URT travellers. Transfer penalties for access journeys increase with the rise of air temperature. The non-linear effects of precipitation on URT feeder transfer penalties were observed. In addition, commuters perceive smaller transfer penalties than other travellers for all of the transfer combinations except for bus-URT transfers. Travelers from remote areas perceive smaller transfer penalties for access trips. Travellers’ loyalty to public transit restrains transfer penalties. The male travellers perceive higher transfer penalties than the female. The elderly travellers impose low transfer penalties to access journeys but high transfer penalties for egress journeys. Finally, the paper explored policy implications and details areas for future research.

This paper proposes a schedule coordination method for transfer problems between an urban rail transit service and its feeder bus service. For given train schedules, a novel mixed-integer nonlinear programming (MINLP) model is formulated to obtain a coordinated bus schedule with the objective of minimizing the weighted sum of passenger transfer costs and bus operating costs. The queuing process for transfer passengers at the transport hubs, which is attributed to both high transfer volumes and limited bus capacity, is discussed and considered in the coordination problem. The vital decision variable is the terminal departure time of each target feeder bus trip within a certain time period. A hybrid solution method that integrates heuristic and enumerative algorithms was developed to solve the MINLP model, and numerical experiments were conducted for different scenarios. The results indicate that the feeder bus schedule coordinated by the developed model is capable of substantially reducing the transfer waiting time for train passengers with a slight increase in bus operating costs.

Summary A schedule consisting of an appropriate arrival time at each time control point can ensure reliable transport services. This paper develops a novel time control point strategy coupled with transfer coordination for solving a multi-objective schedule design problem to improve schedule adherence and reduce intermodal transfer disutility. The problem is formulated using a robust mixed-integer nonlinear programming model. The mixed-integer nonlinear programming model is equivalently transformed into a robust mixed-integer linear programming model, which is then approximated by a deterministic mixed-integer linear programming model through Monte Carlo simulation. Thus, the optimal scheduled arrival time at each time control point can be precisely obtained using cplex. Numerical experiments based on three bus lines and the mass rapid transit system in Singapore are presented, and the results show that the schedule determined using the developed model is able to provide not only reliable bus service but also a smooth transfer experience for passengers. Copyright © 2016 John Wiley & Sons, Ltd.

Eutrema salsugineum, a close relative of Arabidopsis thaliana, is a valuable halophytic model plant that has extreme tolerance to salinity. As posttranscriptional gene regulators, microRNAs (miRNAs) control gene expression and a variety of biological processes, including plant-stress responses. To identify salt-stress responsive miRNAs in E. salsugineum and reveal their possible roles in the adaptive response to salt stress, we chose the Solexa sequencing platform to screen the miRNAs in 4-week-old E. salsugineum seedlings under salt treatment. A total of 82 conserved miRNAs belonging to 27 miRNA families and 17 novel miRNAs were identified and 11 conserved miRNA families and 4 novel miRNAs showed a significant response to salt stress. To investigate the possible biological roles of miRNAs, 1060 potential targets were predicted. Moreover, 35 gene ontology (GO) categories and 1 pathway, including a few terms that were directly and indirectly related to salt stress, were significantly enriched in the salt-stress-responsive miRNAs targets. The relative expression analysis of six target genes was analyzed using quantitative real-time polymerase chain reaction (PCR) and showed a negative correlation with their corresponding miRNAs. Many stress regulatory and phytohormone regulatory cis-regulatory elements were widely present in the promoter region of the salt-responsive miRNA precursors. This study describes the large-scale characterization of E. salsugineum miRNAs and provides a useful resource for further understanding of miRNA functions in the regulation of the E. salsugineum salt-stress response.

The real-time and high-precision transfer alignment between the master and slave systems is the key issue for the airborne distributed Position and Orientation System (POS) to realize real-time and high-precision measurement of multipoint motion parameters. To solve the problem, this paper proposes a transfer alignment method based on federated filter, in which the high-dimensional state vector is divided into two parts and as the state vector of two local filters respectively instead of estimating in a centralized filter. This idea reduces the dimension of the system state vector; thus the computation speed is improved. The results of simulation and static ground experiment show that the proposed method runs faster than centralized filter by more than 10% and its alignment precision has the same level as centralized filter’s.

Aiming at the problems of the accuracy and real-time performance in transfer alignment of airborne distributed position and orientation system (POS), a conditional cubature Kalman filter (CCKF) is proposed. In this method, the state variables of the non-linear mathematical model for transfer alignment are divided into two groups firstly—one group are linear variables that are independent with nonlinear variables, while the other group is composed of nonlinear variables and the linear ones coupled with them. And then, sampling is conducted to the second group of variables to realize the propagation of the cubature points, and the first group of variables is updated by using the conditional distribution of high-dimensional Gaussian random variables at the same time, therefore, time update for all state variables is completed. In the end, measurement update is performed for all state variables. The simulations results show that the proposed method can effectively reduce the computation burden while ensure the accuracy of transfer alignment.

This paper aims at investigating the relationship between the use of the Internet and access to external finance of small and micro businesses, both theoretically and empirically. We first develop a theoretical model to explore how access to the Internet affects the credit availability of firms. The model suggests that access to the Internet can effectively mitigate financing difficulty of firms by alleviating information asymmetry and reducing agency cost, and thus can promote the sustainable development of those firms. The model also shows that access to the Internet can improve social welfare based on aforementioned mechanism. Using China household finance data from China Household Finance Survey, we tested the impact of access to the Internet on access to finance of small and micro businesses. Our empirical results confirm the positive role played by access to the Internet in alleviating financing difficulty of those firms. Moreover, we also found evidence that access to the Internet can reduce borrowers&rsquo, dependence on physical branches of banks when making bank choice decision for loan applications. Our evidence also implies that access to the Internet is conducive to the sustainable development of small and micro businesses via mitigating their financing difficulty.

This paper deals with the problem of state estimation for the transfer alignment of airborne distributed position and orientation system (distributed POS). For a nonlinear system, especially with large initial attitude errors, the performance of linear estimation methods will degrade. In this paper, a nonlinear smoothing algorithm called the unscented particle smoother (UPS) is proposed and utilized in the off-line transfer alignment of airborne distributed POS. In this algorithm, the measurements are first processed by the forward unscented particle filter (UPF) and then a backward smoother is used to achieve the improved solution. The performance of this algorithm is compared with that of a similar smoother known as the unscented Rauch-Tung-Striebel smoother. The simulation results show that the UPS effectively improves the estimation accuracy and this work offers a new off-line transfer alignment approach of distributed POS for multiantenna synthetic aperture radar and other airborne earth observation tasks.

Time of day partition of bus operating hours is a prerequisite of bus schedule design. Reasonable partition plan is essential to improve the punctuality and level of service. In most mega cities, bus vehicles have been equipped with global positioning system (GPS) devices, which is convenient for transit agency to monitor bus operations. In this paper, a new algorithm is developed based on GPS data to partition bus operating hours into time of day intervals. Firstly, the impacts of passenger demand and network traffic state on bus operational performance are analyzed. Then bus dwell time at stops and inter-stop travel time, which can be attained based on GPS data, are selected as partition indexes. For buses clustered in the same time-of-day interval, threshold values of differences in dwell time at stops and inter-stop travel time are determined. The buses in the same time-of-day interval should have adjacent dispatching numbers, which is set as a constraint. Consequently, a partition algorithm with three steps is developed. Finally, a bus route in Suzhou China is taken as an example to validate the algorithm. Three partition schemes are given by setting different threshold values for the two partition indexes. The present scheme in practice is compared with the three proposed schemes. To balance the number of ToD intervals and partition precision, a Benefit Evaluation Index is proposed, for a better time-of-day interval plan.

Airborne distributed Position and Orientation System (POS) depends on transfer alignment to obtain high accuracy motion parameters of sub-systems by using accurate motion information of main system, including position, velocity and attitude. Complicated aircraft flexure will decrease the accuracy of transfer alignment. Usually, the flexure angle is idealized as Markov process with fixed parameters, while these parameters are unknown and time-varying in real application. Accordingly, the accuracy of state model and statistic characters of noise will be incorrect, which consequently increases the error of transfer alignment. To solve the mentioned problem, this paper proposes a parameter identification method and then combines it with UKF. As a result, transfer alignment based on parameter identification UKF (PIUKF) is designed, and verified by simulations and static experiment. The results show that transfer alignment method based on PIUKF improves the accuracy of sub-systems compared with those based on UKF and strong tracking UKF.