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Background: Helicobacter pylori (H. pylori) remains a major cause of gastroduodenal diseases. We aimed to evaluate the burden of this infection, particularly peptic ulcer disease in Vietnamese children. Methods: We enrolled consecutive children referred for esophagogastroduodenoscopy at two tertiary children’s hospitals in Ho Chi Minh City, from October 2019 to May 2021. Children treated with proton pump inhibitors during the last two weeks or antibiotics for four weeks, and those having a previous or interventional endoscopy were excluded. H. pylori infection was diagnosed with either a positive culture or positive histopathology combined with a rapid urease test, or with a polymerase chain reaction of the urease gene. The study was approved by the Ethics Committee and written informed consent/assent was obtained. Results: Among 336 enrolled children aged 4–16 (mean: 9.1 ± 2.4 years; 55.4% girls), H. pylori infection was positive in 80%. Peptic ulcers were detected in 65 (19%), increasing with age, and 25% with anemia. cagA+ strains were detected at a higher rate in children with ulcers. Conclusions: Prevalence of H. pylori and peptic ulcers is high among symptomatic Vietnamese children. It is crucial to have a program for early detection of H. pylori to reduce ulcer risk and gastric cancer later.

Background Neuroblastoma (NB) is among the most common cancers in children. A highly aggressive form of cancer, NB relies on cells in the microenvironment for dissemination particularly cancer associated fibroblast (CAFs). CAFs synthesise the extracellular matrix to create a scaffold for tumor growth thus enabling the carcinogenesis of NB, Collagen, an abundant scaffold protein produced by CAFs, has been implicated in the creation of an optimal tumor microenvironment, however, the expression profile of collagen within NB is not yet known. Methods We characterised collagen expression within the tumor-stroma boundary by microarray and confirmed by qRT-PCR and immunohistochemistry. Results The collagen marker, COL11A1, was also upregulated in NB CD45+ cells and SMA+ CAFs. Furthermore, SMA+ CAFs led to neuroblastoma cell invasion in an in vitro co-culture system which was subsequently attenuated by gene silencing COL11A1. Immunohistochemical staining of clinical tumor samples revealed that high COL11A1 expression in the stroma adjacent to tumour site, significantly associated with advanced cancer stages, age ≥18 months, undifferentiated tumor status, relapse and poor overall survival. Conclusion Collectively, these results suggest that a COL11A1 signature in the NB microenvironment could represent a novel target for therapeutic intervention.

The electrification of propulsion technologies in aerospace engineering has been considered as the future-vision for aviation industries. The Selection of electrified propulsion architecture for a particular mission-flight has become a new challenge. In this paper, a method to study different propulsion architectures and battery sizing for jetliners using multi-physics modeling is presented. The designed approach is then carried out to investigate conventional and hybrid/electric propulsion architectures of a commercial jetliner (Avro RJ-85). Based on the comparative study, an effective propulsion architecture is also suggested. The designed method is expected to help predict effective propulsion architecture for future aviation.

Electrification of aircraft presents great potential in achieving long term emission targets of the sector. Electrification of Ground Support Equipment (GSE) also offers significant opportunity for reducing carbon emissions, as well as the air pollution in and around conventional airports. GSE electrification introduces charging and charging scheduling challenges. In this study, a generic Multi-Input Multi-Output Airport Energy Model (MIMO-AEM) is developed to understand GSE charging requirements and to investigate GSE charging scheduling for existing turnaround procedures. This model is scalable to represent any airport size and will help to quantify the increase in airport electricity requirements and the potential for CO 2 emission benefits from GSE electrification at any airport. The model is capable of investigating the trade-off between the number of electric GSE (e-GSE) required and the number of recharges required for different e-GSE battery pack sizes. The model is also capable of sizing e-GSE battery packs of different GSE types specific to their use case. A test case of a small airport with seven flights per day has been used to investigate the model performance. Initial results show that GSE electrification could offer around 60% CO 2 savings compared to conventional GSE operations. Moreover, compared to non-scheduled charging, scheduled charging of e-GSE by taking account of the minimum CO 2 intensity and minimum electricity price of the grid could reduce both magnitude and duration of peak grid loads up to 23% and 28% respectively. This study has a potential for significant contribution to understanding the system-level requirements of electrification of an airport ecosystem.\ud

An appropriate energy management strategy is essential to enhance the performance of hybrid electric vehicles. A novel modified equivalent fuel-consumption minimization strategy (ECMS) is developed considering the engine operating point deviation from the optimum operating line. This paper focuses on an all-inclusive evaluation of this modified ECMS with other state-of-art energy management strategies concerning battery ageing, engine switching along with fuel economy and charge sustenance. The simulation-based results of a hybrid two-wheeler concept are analysed, which shows that the modified ECMS offers the highest benefit compared to rule-based controllers concerning fuel economy and reduction in engine switching events. However, the improvement in fuel economy using modified ECMS has significant negative potential effects on critical battery parameters influencing battery ageing. The results are analysed and found consistent for two different drive cycles and three different powertrain component configurations. The results show a significant reduction in fuel consumption of up to 21.18% and a reduction in engine switching events of up to 55% with modified ECMS when compared with rule-based strategies. However, there is a significant increase in battery temperature by 31% and battery throughput by 378%, which plays a major role in accelerating battery ageing. This paper emphasizes the need to consider battery-ageing parameters along with other control objectives for a robust assessment of energy management strategies. This study helps in laying down a foundation for future improvements in energy management development and it also aids in establishing a basis for comparing energy management controllers.

This Special Edition of Energies on “Energy Storage and Management for Electric Vehicles” draws together a collection of research papers that critically evaluates key areas of innovation and novelty when designing and managing the high-voltage battery system within an electrified powertrain. The addressed topics include design optimisation, mathematical modelling, control engineering, thermal management, and component sizing.

This paper presents a simple and effective force reflecting joystick controller for applications to bilateral teleoperation in construction machinery. First, this controller is a combination of an advanced force reflecting gain tuner and two local adaptive controllers, master and slave. Second, the force reflecting gain tuner is effectively designed using recursive least square method and fuzzy logics to estimate directly and accurately the environmental characteristics and, consequently, to produce properly a force reflection. Third, the local adaptive controllers are simply designed using fuzzy technique and optimized using a smart leaning mechanism to ensure that the slave follows well any given trajectory while the operator is able to achieve truly physical perception of interactions at the remote site. An experimental master-slave manipulator is setup and real-time control tests are carried out under various environmental conditions to evaluate the effectiveness of the proposed controller.\ud \ud

Aggressive, high-risk neuroblastoma (NB) exhibits an immature differentiation state, profound epigenetic dysregulation and high telomerase activity. It has been suggested that aggressive NB may be treatable by inducing differentiation whereas therapeutic targeting of telomerase is under investigation for multiple cancer types. While epigenetic regulation of the telomerase reverse transcriptase (TERT) promoter has been described in high-risk NB, the exact molecular mechanisms are still not completely understood. Here we used quantitative real-time polymerase chain reaction (PCR), chromatin immunoprecipitation qPCR, quantitative telomeric repeat amplification protocol, and immunoblot techniques to investigate epigenetic regulation of TERT in wild-type and genetically modified NB cell lines. We demonstrated that TERT expression is reduced during 13-cis retinoic acid-induced NB differentiation and that this inversely correlated with increased expression of AT-rich interaction domain 1A (ARID1A), a subunit of the SWItch/sucrose nonfermentable chromatin remodeling complex. We showed that ARID1A directly caused suppression of TERT and was reliant on DNA binding and co-occupancy of the TERT promoter by the SIN3 transcription regulator family member A (SIN3A) repressor complex allowing NB differentiation to proceed. Finally, using data from NB patient cohorts, we reported a significant correlation between low ARID1A expression, elevated expression of TERT, and poorly differentiated, high-risk NB. These results provide insights into a key epigenetic pathway responsible for modulating TERT-driven NB progression, which could represent a target for therapeutic intervention.

Background The study investigates the diagnostic value of calretinin immunohistochemical staining (CIS) on rectal suction biopsies (RSB) in Hirschsprung's disease (HD). Methods A prospective study was conducted at Children's Hospital 2 in Ho Chi Minh City, Vietnam, from January through December 2015. Patients suspected of HD during this period underwent RSB and were followed in order to assess the accuracy of the diagnostic test with CIS compared with conventional histology (H&E). Results A total of 188 children with RSB were investigated. Median age was 7.1 (range 0.2–159) months with 65.4% boys. HD was confirmed in 80 (42.6%) children. There were 1 false positive and no false-negative cases. The sensitivity and specificity were 100% (80/80) and 99.1% (107/108) for CIS and 100% and 85.2% for H&E, respectively. Cohen's kappa coefficient was 0.9891 with a diagnostic accuracy of 99.5% for CIS, compared with 0.8303 and 91.5% for H&E, respectively. There were no serious complications related to the RSB. Conclusion RSB with CIS is a useful diagnostic method for HD, with easy interpretation and no need for cryostat. CIS has a high diagnostic accuracy and should be considered as the primary method for the diagnosis of HD by RSB. Level of evidence: Diagnostic Studies – Level I.

The demand to obtain an accurate and high efficiency hydraulic actuator has been increasing in heavy industries. However, the existence of uncertain, nonlinear, and unknown terms in system dynamics limits the performance of the hydraulic actuator significantly. To deal with these problems, this paper proposes an advanced control approach, named the integrated model-based backstepping (IBS) controller, for position-tracking control of a pump-controlled Electro Hydraulic System (PEHS). First, a mathematical model of the studied system is fully derived in which the structure of the system elements is clearly presented. Second, to realize the control performance in both transient and steady-state responses, and to simplify the design procedure, an advanced backstepping technique is then employed to compensate for the nonlinearities and unknown terms, while the uncertainties are well treated by a novel identification method based on the obtained model. Third, the stability of the closed-loop system is theoretically maintained using Lyapunov functions. Finally, the effectiveness and feasibility of the proposed method are confirmed by comparing with a tuned proportional-integral-derivative (PID) controller and a direct backstepping (DBS) controller in the real-time tracking control of the PEHS to follow various trajectories under different testing conditions.

Recently, electro-hydraulic actuators (EHAs) have shown significant advantages over conventionally valve-controlled actuators. EHAs have a wide range of applications where force or position control with high accuracy is exceedingly necessary. Besides the benefits, however, EHA is a highly complex nonlinear system which causes challenges for both modeling and control tasks. This paper aims to develop an effective control approach for force control of a typical EHA system. This control scheme is considered as an advanced combination of a feedforward neural network - based PID (FNNPID) controller and a fuzzy grey predictor (FGP), shortened as feedforward neural network fuzzy grey predictor (FNNFGP). Here, the FNNPID controller is used to drive the system to desired targets. Additionally, a learning mechanism with robust checking conditions is implemented into the FNNPID in order to optimize online its parameters with respect to the control error minimization. Meanwhile, the FGP predictor with self-tuning ability of the predictor step size takes part in, first, estimating the system output in the near future to optimize the controller parameters in advance and, second, creating a compensating control signal accordingly to the system perturbations and, consequently, improving the control performance. Real-time experiments have been carried out to investigate the effectiveness of the proposed control approach.

The aim of this paper is to develop a novel robust variable sampling period controller (RVSPC) for networked control systems (NCSs) in the presence of random time delays and packet losses. Different from the existing control techniques for NCSs, the RVSPC controller is constructed as a hybrid robust controller with the adaptive variable sampling period. To adapt to the delay variation, a so-called variable sampling period adjuster based on a time delay predictor (TDP) and a time delay and packet detector is designed to adjust effectively the sampling period. To efficiently compensate for the random delays and packet losses, the hybrid controller is designed as a combination of a quantitative feedback theory (QFT)-based robust controller and a robust state feedback controller (RSFC) with adaptive control gain. A smart switch based on the TDP is then used to select properly the main control unit as the QFT or RSFC corresponding to the current delay and packet loss status. Illustrative examples with NCSs including both computation and communication delays and packet losses are finally carried out to illustrate the effectiveness of the proposed method.

Lubrication is one of the most important factors in developing internal combustion engines. And vane pumps are known as potential choices for conducting the engine lubrication systems. To better optimize the lubrication performance, an electronically controlled variable displacement vane pump developed from a typical vane pump is newly introduced in this paper. Firstly, the concept and methodology to design properly an electric actuator to provide an additionally degree of pump control by regulating the pump displacement is carefully considered. Secondly, a control logic is developed to manage the operation of the actuator and subsequently, smoothly varying the pump output in order to satisfy any given lubrication profile. Finally, test rigs are setup to investigate the performances of the fabricated actuator and pump prototype. Practical tests are performed to evaluate the effectiveness of the newly pump design over the typical one.

Recent research on hydraulic systems has mainly focused on energy saving. This is because the efficiency of hydraulic systems is very low even though they have large power-to-size ratios. In mobile hydraulic equipment, conventional hydraulic spool valves with pressure compensators have already been replaced by valve assemblies with four-valve independent metering with electronically controlled pressure compensation. The independent metering concept and microprocessor control have much more potential to save more energy than conventional proportional valve control because of the increased controllability of the system. The primary focus of this study is to reduce the number of Independent Metering Valves (IMV) by introducing one directional control valve. This new model offers two degrees of freedom, i.e., controlling velocity and pressure, just as in conventional IMVs. In the system described here, two of the three independent valves are active during metering. In this paper, the theory behind a new method of flow control based upon load feedback is presented for two of the five distinct metering modes, and its performance is investigated and compared to that of a conventional IMV configuration.

DC motors are used indispensably in industrial applications because they provide such advantages as small size, high speed, low construction cost, and safe operation. A major area of research in DC motors is to determine a better method to measure the torque of motor shaft. The traditional way to measure the mechanical torque of a rotating shaft is attachment a torque transducer in the transmission system between the driving motor and the load. However, this technique requires additional parts for the transmission system, which makes the design more complicated, time consuming, costly in construction, and in many cases impossible to achieve. The purpose of this paper is to present a new method for estimating the load torque of a DC motor shaft by using a novel modelling method based on an adaptive control technique, named as online tuning grey fuzzy PID (OTGFPID). A test rig using a DC motor is setup to investigate the torque behaviour as well as to evaluate the developed estimator. Firstly, mathematical model is developed for the motor. Secondly, the experimental speed-torque data and the optimized motor model is used to optimize the torque estimator. Then the optimized estimator is used to estimate accurately the load torque. Finally, the capability of the optimized torque estimator has been validated with the practical experiments in comparison with a typical estimation method.

Magneto-rheological (MR) fluid damper is a semi-active control device that has recently received more attention because they offer the adaptability of active control devices without requiring the associated large power sources. But inherent nonlinear nature of the MR fluid damper is one of the challenging aspects for utilizing this device to achieve the high performance. So development of an accurate MR fluid damper model is necessary to take the advantages from its unique characteristics. The focus of this paper is to develop an alternative method for modeling a MR fluid damper by using a so-called self-tuning Lyapunov-based fuzzy model (STLFM). Here, the model is constructed in the form of a center average fuzzy interference system, of which the fuzzy rules are designed based on the Lyapunov stability condition. In addition, in order to optimize the STLFM, the back propagation learning rules are used to adjust the fuzzy weighting net. Firstly, experimental data of a damping system using this damper is used to optimize the model. Next, the optimized model is used to estimate online the damping performance in the real-time conditions. The modeling results prove convincingly that the developed model could represent satisfactorily the behavior of the MR fluid damper.

Introduction Patients after pull-through operation for Hirschsprung's disease (HD) are at high risk of defecation disorders. This study aimed at investigating their long-term outcomes and quality of life (QoL) in comparison with controls. Patients and Methods Patients older than 5 years operated on for HD were interviewed to complete detailed questionnaires on bowel function. Patients without neurologic impairment were enrolled in a QoL survey to compare with controls matched for sex and age and selected randomly from the general population using sampling set in a ratio of four controls to one case of HD. Results In total, 53 operated patients were enrolled. Mean age of the patients was 16 ± 8 years, with 68% boys. Rectosigmoid aganglionosis was the most seen form of HD in 38 (72%) cases. Open Soave was performed in 40 (75.5%) cases, and minimally invasive surgery Soave (MIS Soave) in 13 (24.5%) cases. At investigation, prevalence of fecal incontinence and constipation were 22.6 and 13.2%, respectively. Regarding QoL survey, 45 patients and 180 controls were enrolled, excluding 8 patients with neurologic impairment. Thirty-seven (82.2%) patients were classified as having a good QoL (score ≥ 9 points); whereas six had a fair QoL (5–8 points) and two had a poor QoL (< 5 points). QoL score in the cases and the controls were 10.2 ± 2.5 and 11.9 ± 0.4 points, respectively. Long aganglionosis form of HD was significantly associated with a low QoL (score Conclusion Although the QoL of patients operated on for HD in general was with good outcomes, fecal incontinence and constipation still are problematic issues and challenges in a high percentage of patients. Therefore, a long-term and multidisciplinary follow-up is essentially required for these patients.

The aim of this paper is to design, fabricate and control a novel Linear Magnetic Actuator (LMA) for applications such as active magnetic bearing systems to deal with vibration problems in rotating machines. This LMA actuator contains a moving body named ‘mover’ and three driving parts to drive the mover. Firstly, experiments have been conducted on the LMA to derive its mathematical model in order to investigate the generated electro-magnetic force as well as further research. The modeling result in a comparison with the actual system performance show that the electro-magnetic force varied symmetrically with the mover motion defined by the applied current. Secondly, an advanced trajectory controller named online tuning fuzzy PID controller has been designed for the LMA to improve the working performance. Finally, real-time experiments have been carried out to evaluate the tracking performance of the designed LMA control system. The results prove that the LMA driven by the proposed controller could track the desired trajectories with high accuracy.

In forklifts, the machine performance is largely depended on the transmission performance. The aim of this paper is to develop a complete model of transmission control valve (TMV) system of a typical forklift using AMESim simulation tool. By using the developed TMV model, it becomes easy to investigate the system concept, working principle, and performance. In addition, an optimization on the TMV structure can be achieved by using this model with tunable parameters. Simulations have been carried out in a comparison with the actual experiments to verify the model.

This paper presents an advanced design methodology for electric power generation from the vast ocean wave energy. A novel single-buoy heaving device called wave energy converter (WEC) based on hydrostatic transmission (HST), or can be shortened as HSTWEC, is proposed to convert mechanical energy generated by ocean waves into electric energy. Modeling and simulations with both regular and irregular waves were then carried out to investigate working performances of the designed HSTWEC. The results showed that more than 78% of wave energy can be absorbed. In addition, an adaptive controller was designed to improve the performance of the suggested device. Effectiveness of the overall HSTWEC control system was finally proved by simulations.