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Objectives: The study aimed to identify prevalence of H. pylori infection and associated risk factors among pupils of Ho Chi Minh city (HCMC).Methods: A total of 1,476 pupils aged 6–15 years were enrolled in this cross-sectional study using multiple-stage sampling method. Infection status was assessed using stool antigen-test. A questionnaire was used to obtain socio-demographic, behavioral, and environmental factors. Logistic regression was performed to assess possible factors related to the infection.Results: Of the 1,409 children included in the analysis, 49.2% were male and 95.8% were of Kinh ethnicity. About 43.5% of parents completed college or university. The overall prevalence of H. pylori was 87.7%. Infrequency of handwashing with soap after toilet, the use of only water to clean after toilet, crowded living areas, larger family size, and younger age were independently contributing to an increased prevalence of H. pylori.Conclusion:H. pylori infection is highly prevalent in HCMC, and is associated with poor hygienic practices, crowded living areas, larger family size, and younger age. These findings highlight the importance of fecal-oral route and the attribution of crowded living conditions to the spreading of H. pylori in HCMC. Therefore, preventive programs should be set up with a focus on education of hygiene practices, and oriented to those living in crowded conditions.

Objectives: There is no study on Helicobacter pylori (H. pylori) infection in pupils of Ho Chi Minh city (HCMC), the most overcrowded city in Vietnam. Therefore, the aim of this study was to estimate the prevalence of H. pylori and its geographical spread among school-aged children.Methods: A school-based cross-sectional study was conducted among 1854 pupils across 24 districts of HCMC in 2019. Multiple-stage sampling method was used to enroll pupils. We built a four-points index for geographical division based on population density and employees density to evaluate the link between H. pylori and crowded level. Stool samples were analyzed by monoclonal enzyme-immunoassay stool antigen-test to assess the infection status. Logistic regression was performed to assess possible factors related to H. pylori infection.Results: The overall prevalence of H. pylori was 87.7%. There was a linear increasing trend in the infection rate (p < 0.001) across the 4-points index of HCMC and this trend maintained within both age and gender subgroups (p = 0.02).Conclusion: Prevalence of H. pylori was high and it increased with population density or employees density. Therefore, it is crucial to plan and implement the reduction of H. pylori infection programs by targeting the highly concentrated population areas of HCMC.

One of the major challenges in implementing the equivalent fuel consumption minimisation strategy in hybrid electric vehicles is the adaptation of the equivalence factor to real-world driving. In this paper, a novel adaptive equivalent fuel consumption minimisation strategy (A-ECMS) has been developed for a hybrid two-wheeler to further improve fuel savings by predicting the drive cycles and thereby estimating and adapting the equivalence factor online for the ECMS energy management control. A learning vector quantitative neural network (LVQNN)-based classifier was first proposed to recognise the real-world driving cycle based on a fixed time window of past driving information. Along with standardised drive cycles, real-world driving data were used in the learning process to increase the robustness of the learning. The A-ECMS is then capable of regulating its equivalence factors online based on the LVQNN controller output. Numerical simulation results indicated that there was considerable improvement in fuel economy of the vehicle with the proposed methodology, up to 10.7%, compared to the use of traditional ECMS which was manually optimised for a single drive cycle. The average improvement in fuel economy over the ten drive cycles considered for testing is 3.93%.

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 paper develops a newly bicycle concept named smart bicycle (SBIC) with automatic transmission and energy recuperating ability. The SBIC operation is based on a hydrostatic transmission (HST). Several HST designs have been proposed. Moreover, a use of energy converting and storing devices is an optional design for the SBIC to recovery energy during the deceleration or going downhill process, and to support this energy to the hydraulic system during the acceleration or going uphill process. The working efficiency of the bicycle is then increased and could become competitive with the roller-chain technology. Simulations have been carried out to evaluate the working performances of the proposed SBIC concepts.

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 < 8 points), adjusted odds ratio = 9, 95% confidence interval [1.3; 64.1] (p < 0.05). In subscales analyses, the prevalence of each dimension including fecal continence, school absenteeism, unhappiness or anxiety, food restriction, and peer rejection was significantly higher in operated patients than in controls (p <0.001).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. [ABSTRACT FROM AUTHOR]

Hydraulic power systems have greater flexibility and can produce more power than mechanical and electrical systems of equal size. The aim of this paper is to describe results derived from an experimental study on a power hydraulic testing machine with hybrid force and position control. The paper includes the description and fabrication of this novel testing system, named electro-hydraulic load simulator (EHLS), for conducting a performance and stability test in a bench system where force or position control is important. In order to improve the control performance of the loading system and to eliminate or reduce noise, a parallel force and position control strategy using the proportional integral derivative (PID) control method, an online self-tuning fuzzy-neural mechanism, and system identification techniques are also presented in this paper. Experiments are carried out to evaluate the effectiveness of the proposed parallel force and position control method applied to the EHLS system. Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society [ABSTRACT FROM AUTHOR]

Over the last half century, kidney and liver transplantation have been recognized as the treatment of choice for adult and children with end-stage renal or liver failure. Infants present a relative naïve immune system, but they are capable of mounting both cellular and humoral immune responses to the foreign antigens presented by the allograft. Immune monitoring is a way of measuring functional and molecular correlates of immune reactivity which may provide clinically useful information for identifying patients who have an increase risk of acute rejection prior to clinical symptoms or develop transplant tolerance. However, although numerous assays have been shown to predict rejection, to date no assays have been demonstrated to detect or predict transplantation tolerance. This is a summary of the published literature on promising antigen-specific and non-antigen-specific assays used for immunological monitoring in solid organ transplantation. This work also attempts to review their applicability to pediatric transplantation, specifically, pediatric kidney and liver recipients. [ABSTRACT FROM AUTHOR]

This study aims to investigate potential role of granzyme B enzyme-linked immunosorbent spot (GrB ELISPOT) for immunological monitoring in pediatric liver transplantation. Patients and methods: Peripheral blood mononuclear cells from 28 pediatric recipients were serially tested for GrB-producing donor-reactive cells at day 0 pre-transplantation (baseline) and days 7, 14, and 28 post-transplantation. Results: At baseline, no difference of GrB value was found in acute rejection (14/28) compared to normal graft function patients (day 0: 4(3,9) spots versus 5(2.9) spots, respectively: p=0.65). At day 7 post-transplantation, acute rejection patients showed frequencies of GrB EUSPOT higher than those with normal graft function, but the differences observed were not statistically significant (day 7:15(4.9) spots versus 10 (4.0) spots, respectively: p=0.55). GrB increased significantly at day 7 from baseline in the rejection group (15 (4.9) spots versus 4(3.9), respectively p=0.04), whereas corresponding changes were not significant in the group without rejection (10(4.0) versus 5(2.9). respectively: p=0.15). Conclusion: Cr8 ELISPOT pre- transplantation could not predict the occurrence of early post-transplant acute rejection; similarly frequencies at days 7, 14 and 28 could not be correlated with acute rejection in pediatric liver recipients. However, a kinetic study of GrB ELISPOT could be helpful to predict or confirm early rejection in the small group of liver allograft recipients analyzed in this study. [ABSTRACT FROM AUTHOR]

The validation of reliable, non-invasive immunological assays evaluating anti-donor responsiveness in allograft recipients would provide a clinically relevant tool for the early detection of ongoing rejection process as well as for the identification of operational tolerance in the long term. A sequential approach towards immunological monitoring of allografts is proposed in this review: (i) investigations exploring the initial donor-recipient alloresponses, including the analysis of the cytokine network; (ii) investigations regarding graft acceptance and operational tolerance in long-term transplant patients, consisting in the analysis of regulatory T cells and of circulating precursors of dendritic cells, in the measurement of T cell alloreactivity as well as in the study of T cell receptor repertoires. Beside the conventional in vivo and in vitro immunological techniques, the potential applications of molecular imaging in transplantation also deserve further exploration, with particular respect to allograft immune monitoring. Enforced collaboration between transplant clinicians and immunologists will be required to develop the translational research protocols required for the development of immunological monitoring, within an international multicentric network. [ABSTRACT FROM AUTHOR]