ARSENIC REMOVAL FROM GROUNDWATER BY IRON CO PRECIPITATION IN CONTACT FILTER

Joint Research on Environmental Science and Technology for the Eart

Blood pressure percentiles and systemic hypertension-associated factors among children aged between 6 and 15 years in Southern Vietnam

Background: The present study determined blood pressure percentiles in children aged between 6 and 15 years in Southern Vietnam. Material and methods: Blood pressure was measured in a random sample of 1080 students aged 6–15 years who was studying at primary and secondary high schools in My Tho city, Vietnam. A descriptive cross-sectional study was conducted from November 2019 to June 2020. To diagnose children systemic hypertension, the blood pressure must be above the 95th percentile. Data were analyzed by IBM SPSS statistics software version 20.0. The Chi-squared test was employed to evaluate the relationship between systemic hypertension and child demographic characteristics including gender and obesity. Results: The results showed that the 95th percentiles of systolic and diastolic blood pressure of the children was 110/70 mm Hg in the 6-year-old group, 120/75 mm Hg in the 7 to12-year-old group and 125/80 mm Hg in the 13 to 15-year-old group, respectively. The rate of systemic hypertension in the children was 10% whereas boys had a 1.2 time higher risk of systemic hypertension than girls (p > 0.05). Obese children had an 8.6 time higher risk of systemic hypertension than non-obese ones (p < 0.001). Conclusion: The blood pressure percentile chart of school children aged 6–15 years were reported here for the first time in Vietnam. The results provided useful information in early diagnosis and timely treatment of systemic hypertension in children

PILOT SCALE STUDY ON AMMONIUM REMOVAL IN PHAP VAN WATER PLANT, HANOI CITY

Joint Research on Environmental Science and Technology for the Eart

Sintering behavior and physical properties of Bi0.5(Na1–xKx)0.5SnO3 lead-free ceramics

In this study, Bi0.5(Na1–xKx)0.5SnO3 (BNKS) ceramics (x = 0, 0.1, 0.2, 0.3, and 0.4) were fabricated via ultrasound wave before milling. The time of ball milling decreased from 20 to 1 h. The X-ray diffraction patterns show that the BNKS has a single-phase structure. When the potassium content increases, the phase structure of the ceramics changes from rhombohedral to tetragonal. When sintered at 1100 °C and x = 0.2, the ceramics’ physical properties are the best with the mass density of 5.59 g/cm3, the electromechanical coupling constants kp of 0,31 and kt of 0.27, the remanent polarization of      11.9 µC/cm; the dielectric constant εr of 1131, and the highest dielectric constant emax of 4800

Neutrophil to lymphocyte with monocyte to lymphocyte ratio and white blood cell count in prediction of lung cancer

BackgroundLung cancer is the most common cause of cancer deaths in both sexes, while it is very difficult for screenings and early detection. AimsThis study aims to clarify the role of systematic inflammation markers, including white blood cell (WBC), neutrophil (NEU), monocyte (MONO), platelet (PLT), neutrophil to lymphocyte ratio (NLR), monocyte to lymphocyte ratio (MLR) and platelet to lymphocyte ratio (PLR) in prediction of lung cancer. Methods A case-control study was conducted on 1,315 primary lung cancer patients and 1,315 healthy adults with matched age and gender at Cho Ray hospital. NLR, MLR and PLR were calculated by using neutrophil, lymphocyte, monocyte and platelet count which were recalled from laboratory database. With 600 cases in the derivation set, the logistic regression with univariate analysis was used to identify the impacted marker, then developing the optimal prediction model for lung cancer by logistic regression with multivariate method. The diagnostic values of optimal model consisting of sensitivity (Sen), specificity (Spe), positive predictive value (PPV), negative predictive value (NPV) and the area under the ROC curve (AUC) value were extracted and verified on all data, in validation set. Results The median values of WBC, NEU, MONO, PLT, NLR, MLR and PLR in lung cancer were not significantly difference between histological subtypes and clinical stages (p > 0.05), but higher than the values in control group (p < 0.01). Multivariates analysis shows that NLR, MLR and WBC were three parameters that have the significant impact of the optimal prediction model (p < 0.01). The AUC value, sensitivity and specificity of the optimal model for lung cancer detection were 0.881, 73.5 per cent (95 per cent CI:70.3–76.6) and 87.7 per cent (95 per centCI:85.2–89.9), respectively. Whereas, the PPV and NPV values of prediction model were 85.7 per cent (95 per cent CI:82.8–88.2) and 76.8 (95 per centCI:73.9–79.5), respectively. Among three biomarkers, the AUC values of NLR (0.853) and MLR (0.842) were higher than the value of WBC (0.752) (p < 0.01).ConclusionThe results of this study show that NLR with MLR and WBC in optimal prediction model are promising biomarkers for lung cancer screening that could be applied in clinical practice with the advantage of convenience and low cost

Acceptance and user experiences of a wearable device for the management of hospitalized patients in COVID-19–designated wards in Ho Chi Minh City, Vietnam: action learning project

Background: Wearable devices have been used extensively both inside and outside of the hospital setting. During the COVID-19 pandemic, in some contexts, there was an increased need to remotely monitor pulse and saturated oxygen for patients due to the lack of staff and bedside monitors. Objective: A prototype of a remote monitoring system using wearable pulse oximeter devices was implemented at the Hospital for Tropical Diseases in Ho Chi Minh City, Vietnam, from August to December 2021. The aim of this work was to support the ongoing implementation of the remote monitoring system. Methods: We used an action learning approach with rapid pragmatic methods, including informal discussions and observations as well as a feedback survey form designed based on the technology acceptance model to assess the use and acceptability of the system. Based on these results, we facilitated a meeting using user-centered design principles to explore user needs and ideas about its development in more detail. Results: In total, 21 users filled in the feedback form. The mean technology acceptance model scores ranged from 3.5 (for perceived ease of use) to 4.4 (for attitude) with behavioral intention (3.8) and perceived usefulness (4.2) scoring in between. Those working as nurses scored higher on perceived usefulness, attitude, and behavioral intention than did physicians. Based on informal discussions, we realized there was a mismatch between how we (ie, the research team) and the ward teams perceived the use and wider purpose of the technology. Conclusions: Designing and implementing the devices to be more nurse-centric from their introduction could have helped to increase their efficiency and use during the complex pandemic period

Wearable devices for remote monitoring of hospitalized patients with COVID-19 in Vietnam

Patients with severe COVID-19 disease require monitoring with pulse oximetry as a minimal requirement. In many low- and middle- income countries, this has been challenging due to lack of staff and equipment. Wearable pulse oximeters potentially offer an attractive means to address this need, due to their low cost, battery operability and capacity for remote monitoring. Between July and October 2021, Ho Chi Minh City experienced its first major wave of SARS-CoV-2 infection, leading to an unprecedented demand for monitoring in hospitalized patients. We assess the feasibility of a continuous remote monitoring system for patients with COVID-19 under these circumstances as we implemented 2 different systems using wearable pulse oximeter devices in a stepwise manner across 4 departments

Spatiotemporal evolution of SARS-CoV-2 Alpha and Delta variants during large nationwide outbreak of COVID-19, Vietnam, 2021

We analyzed 1,303 SARS-CoV-2 whole-genome sequences from Vietnam, and found the Alpha and Delta variants were responsible for a large nationwide outbreak of COVID-19 in 2021. The Delta variant was confined to the AY.57 lineage and caused >1.7 million infections and >32,000 deaths. Viral transmission was strongly affected by nonpharmaceutical interventions

Safety and efficacy of fluoxetine on functional outcome after acute stroke (AFFINITY): a randomised, double-blind, placebo-controlled trial

Background Trials of fluoxetine for recovery after stroke report conflicting results. The Assessment oF FluoxetINe In sTroke recoverY (AFFINITY) trial aimed to show if daily oral fluoxetine for 6 months after stroke improves functional outcome in an ethnically diverse population. Methods AFFINITY was a randomised, parallel-group, double-blind, placebo-controlled trial done in 43 hospital stroke units in Australia (n=29), New Zealand (four), and Vietnam (ten). Eligible patients were adults (aged ≥18 years) with a clinical diagnosis of acute stroke in the previous 2–15 days, brain imaging consistent with ischaemic or haemorrhagic stroke, and a persisting neurological deficit that produced a modified Rankin Scale (mRS) score of 1 or more. Patients were randomly assigned 1:1 via a web-based system using a minimisation algorithm to once daily, oral fluoxetine 20 mg capsules or matching placebo for 6 months. Patients, carers, investigators, and outcome assessors were masked to the treatment allocation. The primary outcome was functional status, measured by the mRS, at 6 months. The primary analysis was an ordinal logistic regression of the mRS at 6 months, adjusted for minimisation variables. Primary and safety analyses were done according to the patient's treatment allocation. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12611000774921. Findings Between Jan 11, 2013, and June 30, 2019, 1280 patients were recruited in Australia (n=532), New Zealand (n=42), and Vietnam (n=706), of whom 642 were randomly assigned to fluoxetine and 638 were randomly assigned to placebo. Mean duration of trial treatment was 167 days (SD 48·1). At 6 months, mRS data were available in 624 (97%) patients in the fluoxetine group and 632 (99%) in the placebo group. The distribution of mRS categories was similar in the fluoxetine and placebo groups (adjusted common odds ratio 0·94, 95% CI 0·76–1·15; p=0·53). Compared with patients in the placebo group, patients in the fluoxetine group had more falls (20 [3%] vs seven [1%]; p=0·018), bone fractures (19 [3%] vs six [1%]; p=0·014), and epileptic seizures (ten [2%] vs two [<1%]; p=0·038) at 6 months. Interpretation Oral fluoxetine 20 mg daily for 6 months after acute stroke did not improve functional outcome and increased the risk of falls, bone fractures, and epileptic seizures. These results do not support the use of fluoxetine to improve functional outcome after stroke

Evaluation of DOC removal by advanced oxidation processes as pre-treatment of the biological process using low ozone doses

The presence of organic contaminants in raw water and high chlorine demand in drinking water treatment plants (DWTPs) in Ho Chi Minh City (HCMC) has contributed to the increased formation of disinfectant by-products (DBPs) in tap water. To address this issue, DWTPs require alternative methods to reduce the potential formation of DBPs and chlorine consumption. This study investigated the combination of various advanced oxidation processes (AOPs), including O3 only, O3-H2O2, and O3-UV, coupled with the biological activated carbon (BAC) process to remove the natural organic matter (NOM) as a precursor to DBPs. Batch-scale AOP experiments were conducted under different operating conditions, and the O3-UV process demonstrated the highest bDOC/DOC ratio, indicating the formation of biodegradable transformation products rather than mineralization. The integrated O3-UV-BAC process reduced DOC and UV254 by 40% and 52%, respectively. The empirical models showed that the O3-UV-BAC process significantly achieved high THMFP and HAAFP removals. Using ozonation or AOPs coupled with biological process to remove DBP precursors and organic micropollutants from the Saigon River water can be a potential method for ensuring a safe water supply system in HCMC