Assessing and improving rational antimicrobial use in urban and rural health care facilities in Vietnam

The global problem of antimicrobial resistance (AMR) is particularly pressing in developing countries including Vietnam, where the infectious disease burden is high and cost constrains the replacement of older antimicrobials with newer, more expensive ones. Along with surveillance and infection control, responsible use of antimicrobials is one of the main objectives of the Vietnam National Action Plan on combating AMR. This thesis aims to get a better understanding of how antimicrobials are used in the Vietnamese community and how its use can be improved, to tailor evidence-based interventions and inform policies in controlling AMR. To assess the current situation of community access and use of antimicrobials and identify determinants associated with current practice, an observational study was conducted in 30 private pharmacies in northern Vietnam. This study was followed by a randomised controlled trial (RCT) to evaluate a point of care (POC) C-reactive protein (CRP, a biomarker of inflammation) test in reducing unnecessary antimicrobial prescribing for patients with non-severe acute respiratory infections (ARI) and analysis of the economic impact and acceptance of this intervention among users. In private pharmacies, profit incentives coupled to poor knowledge about AMR are key drivers of over the counter dispensing of antimicrobials regardless the existence of regulations. Using a simple rapid blood test to identify customers who do not benefit from antimicrobial therapy would be a potential solution. Primary healthcare stations where over-prescription of antimicrobials for self-limiting infections are common, were chosen for the intervention. CRP POC testing reduced unnecessary AB use for ARI patients without compromising patient’s recovery. This supports and extends findings from European trials by showing that such a stewardship approach is applicable even in resource constrained settings. However, there were several obstacles identified among users regarding test adherence associated with large between-site heterogeneity that need to be addressed to maximize the intervention’s effect in the future. More importantly, our cost analysis indicated that to encourage adoption at scale, proper funding mechanisms to balance the invested costs and achieve global impact on AMR is recommended. In summary, antimicrobial use in Vietnam is largely uncontrolled both in the community and the healthcare system leading to overuse and over-prescription for non-severe ARI. Use of commercially available CRP tests can be an effective, scalable and economically viable approach, even in highly resource-constrained settings. For the future, we are looking at ways to optimise use of POC biomarker testing in primary healthcare and private pharmacy setting. The potential for biomarker based tests to be combined with rapid pathogen detection, enhancing test algorithm adherence, use of CRP tests with equal financial incentives as as selling of antimicrobials and introducing pay for performance mechanisms may be crucial parts for optimisation

Several prognosis factors of severe pertussis in children treated at Vietnam National Children’s Hospital (2019-2020)

A prospective, descriptive study was conducted on 382 pediatric patients diagnosed with pertussis at Vietnam National Children’s Hospital over a two-year period, from January 1st, 2019, to December 31st, 2020. Of all patients participating in this study, children with severe conditions accounted for 30.1% (115/382). Several factors were found to be associated with the risk of this condition with odds ratios (OR) and 95% confidence intervals (CI), including a decrease in the duration of the onset phase by 5 days [OR 1.53, 95% CI: 1.002-2.34], fever [2.49, 1.18-5.24], cyanosis [9.59, 2.9-31.7], pneumonia [14.45, 6.06-34.5], pulmonary hypertension [4.15, 1.02-16.83], an increase of 10 g/l in white blood cell (WBC) count in the full blood count (FBC) test [1.39, 1.05-1.84], a 5-cycle reduction in Cycle threshold (Ct) value in the pertussis real-time PCR test [1.36, 1.01-1.84], and superinfection [3.94, 1.84-8.48 times]. A WBC count in FBC of ≥30 g/l could be used as a prognostic factor for the risk of severe illness condition (sensitivity 46.1%, specificity 90.6%), the requirement for mechanical ventilation (sensitivity 57.1%, specificity 88.5%), and mortality (sensitivity 100%, specificity 91%)

NUTRIENT RECOVERY AND POLLUTANT REMOVAL FROM PIGGERY WASTEWATER BY SPIRULINA CULTIVATION

Spirulina is noticed for great applications on food supplements, animal feeds, pharmaceutical, cosmetics, biofuel, fertilizer, etc. Spirulina cultures in wastewaters could enhance the feasibility of commodities due to its ability to reduce the cost of biomass production and remove pollutants in wastewaters. This study investigates the effects of wastewater pretreatment using various aeration periods (i.e. from 3 to 7 days), the supplement of bicarbonate and N:P ratios on the growth of Spirulina sp. HH to produce protein-rich biomass. The work showed that Spirulina sp. had the ability to effectively remove ammonium, with the highest efficiencies up to 99.9 %. However, the high concentration of ammonium in wastewater, from 125 mg N/L upward, caused a decline in the growth rate of Spirulina. The growth and remediation potential of Spirulina sp. were in the best condition with the N:P ratio of the medium in the range of 19:1-22:1. This study suggested a procedure to cultivate Spirulina sp. in piggery wastewater and remove pollutants efficiently

FIELD TEST ON CLEANING OF OIL POLLUTION ON NHATRANG BEACH OF VIETNAM

Joint Research on Environmental Science and Technology for the Eart

Evaluation of Phacoemulsification Cataract Surgery Outcomes After Penetrating Keratoplasty

BACKGROUND: Cataract is one of the reasons which causes impaired visual acuity (VA) of the eyes after penetrating keratoplasy (PK), which can be treated by cataract surgery after PK or triple procedure. Cataract surgery after PK has advantages that parameters of the eyes such as axial length, anterior chamber depth (ACD) as well as corneal curvature are stabilized after removing all sutures postoperatively, and intraocular lens (IOL) power can be calculated correctly. Therefore, postoperative VA will be improved significantly. In Vietnam, there have not been any study about cataract surgery after PK, therefore we conduct this research. AIM: To evaluate the outcomes of phacoemulsification cataract surgery following primary PK. METHODS: Non-randomized controlled intervention study. Ninteen eyes (19 patients) that underwent phacoemulsification plus IOL insertion after initial PK in Cornea department, Vietnam National Institute of Ophthalmology, from December 2013 to September 2014. RESULTS: All patients presented with reduced VA, including 17 eyes (89.9%) with VA ≤ 20/200, mean astigmatism was 7.9 ± 1.0 D. Clear corneal grafts in 16 eyes while corneal opacity was seen in 3 eyes. All eyes with cataract were diagnosed from grade 2. After cataract surgery, improved VA > 20/200 was achieved in 72.22% of cases. There was a markable reduce of postoperative astigmatism with 1,8 ± 0.8 D (p < 0.05). However, the immunologic graft reaction was presented in one eye, and two edematous corneas also reported after cataract surgery. After treatment, there was one cornea achieved its clarity. CONCLUSION: Phacoemulsification cataract surgery following initial PK showed good outcomes with improved postoperative VA, reduced astigmatism, and the ultimate graft survival rate was high

A Nonlinear Sliding Mode Controller for IPMSM Drives with an Adaptive Gain Tuning Rule

This paper presents a nonlinear sliding mode control (SMC) scheme with a variable damping ratio for interior permanent magnet synchronous motors (IPMSMs). First, a nonlinear sliding surface whose parameters change continuously with time is designed. Actually, the proposed SMC has the ability to reduce the settling time without an overshoot by giving a low damping ratio at the initial time and a high damping ratio as the output reaches the desired setpoint. At the same time, it enables a fast convergence in finite time and eliminates the singularity problem with the upper bound of an uncertain term, which cannot be measured in practice, by using a simple adaptation law. To improve the efficiency of a system in the constant torque region, the control system incorporates the maximum torque per ampere (MTPA) algorithm. The stability of the nonlinear sliding surface is guaranteed by Lyapunov stability theory. Moreover, a simple sliding mode observer is used to estimate the load torque and system uncertainties. The effectiveness of the proposed nonlinear SMC scheme is verified using comparative experimental results of the linear SMC scheme when the speed reference and load torque change under system uncertainties. From these experimental results, the proposed nonlinear SMC method reveals a faster transient response, smaller steady-state speed error, and less sensitivity to system uncertainties than the linear SMC metho

Feature selection methods and sampling techniques to financial distress prediction for Vietnamese listed companies

The research is taken to integrate the effects of variable selection approaches, as well as sampling techniques, to the performance of a model to predict the financial distress for companies whose stocks are traded on securities exchanges of Vietnam. A firm is financially distressed when its stocks are delisted as requirement from Vietnam Stock Exchange because of making a loss in 3 consecutive years or having accumulated a loss greater than the company’s equity. There are 12 models, constructed differently in feature selection methods, sampling techniques, and classifiers. The feature selection methods are factor analysis and F-score selection, while 3 sets of data samples are chosen by choice-based method with different percentages of financially distressed firms. In terms of classifying technique, logistic regression together with SVM are used in these models. Data are collected from listed firms in Vietnam from 2009 to 2017 for 1, 2 and 3 years before the announcement of their delisting requirement. The experiment’s results highlight the outperformance of the SVM model with F-score selection method in a data sample containing the highest percentage of non-financially distressed firms

A Nonlinear Sliding Mode Controller for IPMSM Drives with an Adaptive Gain Tuning Rule

This paper presents a nonlinear sliding mode control (SMC) scheme with a variable damping ratio for interior permanent magnet synchronous motors (IPMSMs). First, a nonlinear sliding surface whose parameters change continuously with time is designed. Actually, the proposed SMC has the ability to reduce the settling time without an overshoot by giving a low damping ratio at the initial time and a high damping ratio as the output reaches the desired setpoint. At the same time, it enables a fast convergence in finite time and eliminates the singularity problem with the upper bound of an uncertain term, which cannot be measured in practice, by using a simple adaptation law. To improve the efficiency of a system in the constant torque region, the control system incorporates the maximum torque per ampere (MTPA) algorithm. The stability of the nonlinear sliding surface is guaranteed by Lyapunov stability theory. Moreover, a simple sliding mode observer is used to estimate the load torque and system uncertainties. The effectiveness of the proposed nonlinear SMC scheme is verified using comparative experimental results of the linear SMC scheme when the speed reference and load torque change under system uncertainties. From these experimental results, the proposed nonlinear SMC method reveals a faster transient response, smaller steady-state speed error, and less sensitivity to system uncertainties than the linear SMC metho

Dry Eyes Status on Des Scale and Related Factors in Outpatients at Vietnam National Institute of Ophthalmology

BACKGROUND: Dry eye (DE) can effect on quality of life by pain, inability to perform certain activities that require prolonged attention (driving, reading,…) and productivity at work and finally effect to Q0L associated with DE. OSDI is scale questionnaire is created team to measure the quality of life related to ocular surface disease. AIM: To describe the dry eye disease according to OSDI scale and related factors of this disease. METHODS: A cross-sectional descriptive study was carried out on outpatients (≥ 16-year-old) who were examined and diagnosed with dry eyes at Vietnam National Institute Of Ophthalmology from April to July 2018. Data was collected using the OSDI questionnaire. RESULTS: The average age of participants was 44.6 years; 80.9% of patients were female; 39.9% were identified having mild dry eye. The related factors have been identified that associated with severe dry eye, including age OR = 1.03 (95%CI: 1.01-1.05, p = 0.005), binocular good vision OR = 0.11 (95%CI: 0.05-0.23; p < 0.0001), medical history OR = 17.09 (95%CI: 2.24-130.25; p < 0.0001), chronic conjunctivitis OR = 0.36 (95%CI: 0.14-0.91; p = 0.027), refractive errors OR = 0.14 (95%CI: 0.04-0.48; p < 0.0001), Sjogren's syndrome OR = 31.13 (95%CI: 7.08-136.76; p < 0.0001). CONCLUSION: Several related factors have been identified associated with severe dry eye, including: age, binocular good vision, medical history, chronic conjunctivitis, refractive errors, Sjogren's syndrome

Secular trend, seasonality and effects of a community-based intervention on neonatal mortality: follow-up of a cluster-randomised trial in Quang Ninh province, Vietnam.

BACKGROUND: Little is know about whether the effects of community engagement interventions for child survival in low-income and middle-income settings are sustained. Seasonal variation and secular trend may blur the data. Neonatal mortality was reduced in a cluster-randomised trial in Vietnam where laywomen facilitated groups composed of local stakeholders employing a problem-solving approach for 3 years. In this analysis, we aim at disentangling the secular trend, the seasonal variation and the effect of the intervention on neonatal mortality during and after the trial. METHODS: In Quang Ninh province, 44 communes were allocated to intervention and 46 to control. Births and neonatal deaths were assessed in a baseline survey in 2005, monitored during the trial in 2008-2011 and followed up by a survey in 2014. Time series analyses were performed on monthly neonatal mortality data. RESULTS: There were 30 187 live births and 480 neonatal deaths. The intervention reduced the neonatal mortality from 19.1 to 11.6 per 1000 live births. The reduction was sustained 3 years after the trial. The control areas reached a similar level at the time of follow-up. Time series decomposition analysis revealed a downward trend in the intervention areas during the trial that was not found in the control areas. Neonatal mortality peaked in the hot and wet summers. CONCLUSIONS: A community engagement intervention resulted in a lower neonatal mortality rate that was sustained but not further reduced after the end of the trial. When decomposing time series of neonatal mortality, a clear downward trend was demonstrated in intervention but not in control areas. TRIAL REGISTRATION NUMBER: ISRCTN44599712, Post-results