In this study, an integrated hurdle modelling workflow combining ATR-FTIR and machine learning was developed for the simultaneous quantification of levodopa (LD), carbidopa (CD), and benserazide (BZ) in anti-Parkinson's medication. A calibration set of 103 synthetic pellets was prepared with wide concentration ranges for the three active pharmaceutical ingredients (APIs), 0-80% w/w for LD, 0-40% w/w for BZ; and 0-8% w/w for CD, and analysed by ATR-FTIR and HPLC-DAD reference method. Nine pellets prepared from three commercial medications were used for external evaluation and calibration transfer. A two-stage hurdle model was employed for each analyte, including a classifier for presence/absence and a regressor fitted only on positive samples to predict concentration. The modelling workflow comprised four modules, in which the Savitzky-Golay first derivative, combined with the standard normal variate (SNV) on mean spectra, was the most suitable preprocessing method. Logistic regression for LD and BZ, and supported vector classification (SVC) for CD were selected as optimal classifiers, while random forest (RF) regression in the half spectral region (675-1800 cm(-1)) was the best overall regressor for all APIs. When applied to commercial samples, the model classifiers correctly identified the presence/absence of all APIs, and calibration transfer using only six additional commercial pellets significantly reduced bias for all three APIs and achieved a high AGREE green score (0.75) at the same time. These results show that ATR-FTIR, combined with a carefully designed hurdle model workflow, can provide a rapid and green screening tool for multi-API in anti-Parkinson's medications.

Paper-making is one of the potential sources of PFASs contamination in groundwater because the collection and treatment of sewage from paper-making activities have not been controlled effectively. For this reason, in this study, 12 PFASs in groundwater were analyzed during the dry season (n = 18) and the rainy season (n = 22) in Phong Khe (Bac Ninh), the largest paper-making village in Northern Vietnam. The results showed that the total PFAS concentrations ranged from non-detectable levels to 15.06 ng/L during the dry season and from non-detectable levels to 9.92 ng/L during the rainy season. Short-chain PFASs (C < 9) were more commonly detected in groundwater compared to long-chain PFASs. While perfluorohexane sulfonic acid (PFHxS) and perfluorooctanesulfonic acid (PFOS) were predominant in groundwater samples during the dry season, perfluorooctanoic acid (PFOA), perfluorohexanoic acid (PFHxA), and perfluoroheptanoic acid (PFHpA) contributed significantly to the composition of PFASs during the rainy season. Although these PFASs have not posed a health risk through groundwater consumption, future research is needed to investigate further the levels and distribution of these compounds in different environmental compartments within other potential craft villages.

Bài báo trình bày kết quả nghiên cứu xác định một số thông số cơ bản của viên nén năng lượng sản xuất từ cây lục bình như: Mật độ khối, độ bền cơ học, độ ẩm toàn phần, hàm lượng tro, hàm lượng chất bốc, hàm lượng carbon cố định và nhiệt trị cao. Phương pháp phân tích nhiệt trọng lượng (TGA) được sử dụng để phân tích đặc tính cháy và phương pháp kính hiển vi điện tử quét (SEM) được dùng để quan sát ảnh hình thái cấu trúc của viên nén năng lượng từ cây lục bình. Ảnh hưởng của hai thông số là áp suất nén và kích cỡ nguyên liệu đến mật độ khối của viên nén năng lượng cũng được đánh giá. Kết quả chỉ ra rằng hầu hết các chỉ tiêu của viên nén năng lượng sản xuất từ lục bình đáp ứng được TCVN 13534:2022 về viên nén nhiên liệu. Áp suất nén khoảng 150 MPa và kích cỡ nguyên liệu nhỏ hơn 2 mm là phù hợp cho quá trình nén ép tạo viên nén năng lượng. Giản đồ phân tích nhiệt trọng trường (TG) và phân tích nhiệt trọng trường đạo hàm (DTG) cho thấy viên nén năng lượng từ cây lục bình có tiềm năng làm nhiên liệu sinh học hiệu quả nhờ khả năng phân hủy nhiệt nhanh. Các kết quả từ nghiên cứu này cho thấy rằng việc sử dụng cây lục bình làm nguyên liệu để sản xuất viên nén năng lượng là khả thi và có cơ sở.

Groundwater quality in rapidly urbanising megacities such as Hanoi is increasingly threatened by over-extraction and widespread contamination. Despite heavy reliance on groundwater as the primary water source, its quality has rarely been assessed comprehensively and objectively. This study proposes a machine learning - based approach for evaluating groundwater quality in Van Phuc, where aquifers are affected by intensive exploitation and arsenic pollution. The Extreme Gradient Boosting (XGBoost) algorithm was employed to rank and select parameters according to their importance to overall water quality. Among the eleven input indicators, eight parameters, including As, total hardness, Mn, Na, Cl-, NH4+, Fe, and F-, showed substantial contributions, with As identified as the most influential variable, whereas pH, SO42-, and total dissolved solids (TDS) contributed negligibly. Four aggregation functions were employed to compute the overall groundwater quality index (GWQI), and the National Sanitation Foundation (NSF) model yielded the most consistent and reliable classification for the study area. Application of the developed framework indicated that only one sample exhibited good water quality, while the remainder fell into fair (41.4%), marginal (20.7%), and poor (34.5%) categories. Spatial water quality patterns were closely aligned with hydrogeochemical zonation: poor-to-marginal conditions predominated within the Holocene aquifer, improving with depth across the redox transition zone, and generally achieving better quality in the Pleistocene aquifer. The proposed approach provides a transparent and transferable tool for groundwater quality assessment in stressed urban aquifers, reducing subjectivity while enhancing interpretability and supporting evidence-based water management.

Arsenic contamination in groundwater represents a significant public health threat to millions of people globally, particularly within the Red River Delta region of Vietnam. This study aims to assess the seasonal fluctuations in arsenic concentration and the underlying hydrogeochemical dynamics of groundwater at Van Phuc, Thanh Tri, Hanoi. Groundwater samples were collected from 17 wells, with depths ranging from 25 to 54 meters, during three distinct seasons: pre-monsoon, monsoon, and post-monsoon. Physicochemical analysis indicates that groundwater quality is predominantly influenced by local biogeochemical processes within the aquifer, coupled with year-round river recharge. In contrast, anthropogenic impacts, such as irrigation and wastewater discharge, appear to exert minimal influence. Arsenic concentrations exhibited a slight increase, from 132 µg/L in the pre-monsoon to 141 µg/L in the monsoon and reaching 145 µg/L in the post-monsoon season. Notably, seasonal fluctuations were more pronounced in shallow groundwater (<30 meters), with a progressive reduction in variability as the distance from the Red River increased. These fluctuations are driven by arsenic mobility under varying redox conditions and the local geohydrochemical processes. Additionally, high phosphate concentrations were found to enhance the arsenic variation in groundwater. Health risk assessments revealed a high hazard index (HI > 1) and unacceptable carcinogenic risk (ILCR > 10⁻⁴) in most wells, underscoring the need for mitigation measures. This study provides insights into the seasonal hydrogeochemical processes governing arsenic contamination, with implications for groundwater management in affected regions. Further research is needed to refine mitigation approaches and reduce exposure risks.

In this study, a green analytical method taking advantage of capillary electrophoresis using capacitively coupled contactless conductivity detection (CE-C4D) was developed and validated for the rapid determination of perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) in water samples. The optimal background electrolyte (BGE) consisted of 100 mM of tris(hydroxymethyl)aminomethane with a pH of 9.25 adjusted using acetic acid (Tris/Ace), 0.2 mM of HP-beta-CD, and 12 % (v/v) of isopropanol (IPA). Under these conditions, the instrumental detection limit (IDL) for PFOS and PFOA was 0.23 and 0.21 mg/L, respectively. The precision in terms of relative standard derivation (RSD%) of peak areas and migration times were less than 10 % for both intra-day (n = 7) and inter-day (n = 5) measurements. The recoveries of spiked samples were within the 90-110 % range. The developed CE-C4D was applied for the analysis of six different types of water samples, namely surface water, rainwater, underground water, tap water, bottled water, and seawater. The results demonstrated a less than 10 % difference between the results obtained from CE-C4D and liquid chromatography-tandem mass spectroscopy (LC-MS/MS) methods, except for the seawater matrix.

In this study, the green analytical methods based on capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C⁴D) and high-performance liquid chromatography with diode-array detection (HPLC-DAD) were developed for the simultaneous analysis of levodopa (LVDP), carbidopa (CBDP), and benserazide (BSRZ) as main active ingredients of Parkinson's drugs. Optimal conditions for both CE and HPLC methods were established using response surface methodology with central composite design (RSM-CCD), considering the important parameters as variable factors such as background electrolyte (BGE) concentration and applied voltage for CE; mobile phase concentration, pH-value, surfactant concentration, and flow rate for HPLC. For CE-C⁴D, formic acid (2.5 M, pH 1.68) at 18 kV was identified as optimal, and limits of detections (LODs) were determined to be 0.29 - 0.47 mg/L. For HPLC-DAD, a phosphate buffer (54.2 mM, pH 3.80) with 121 μM sodium 1-octanesulfonate at a flow rate of 1.06 mL/min was optimized, providing LODs of 0.18 - 0.35 mg/L. The greenness degree of the developed procedures was evaluated using the AGREE metric, with CE-C4D achieving a higher score (0.74) compared to HPLC-DAD (0.58), attributed to reduced reagent consumption, shorter analysis times (10 min vs. 15 min), and lower energy use. These methods were successfully applied to analysis of commercial drug samples, demonstrating comparable performance to confirm a prefer in favour for CE studies in terms of offering enhanced environmental sustainability and efficiency for routine pharmaceutical analysis.

In this research, the analytical method was developed and evaluated for determining phenol and its nine derivatives belong to the US EPA priority pollutant list in water samples by using dual -channeled capillary electrophoresis (CE) coupled with two types of optical detectors, namely LED -induced fluorescence (LEDIF) and ultraviolet (UV) detectors. The optimal background electrolytes for the first and second CE channels were 20 mM borate (pH 9.80) with 400 mu M fluorescein and 55 mM borate (pH 11.75), respectively. The two-step liquid -liquid extraction (LLE) was used for sample preparation and enrichment, in which phenol and its derivatives were extracted from the aqueous phase using 10 mL of n-hexane/1-octanol (60/40, v/v) and then were back extracted into a 0.1 M NaOH as a final acceptor phase. Under the optimal CE and two-step LLE conditions, the enrichment factors of 10 phenols were 184 - 1120 -fold, and the method detection limits were lowered to 0.02-0.60 mu g/L. The obtained intra-day and inter -day precisions in terms of relative standard deviations (RSD) were between 4.0 and 7.3 % and 6.7 and 14 %, respectively. This approach was used to determine phenols in water samples, with recoveries ranging from 82.0 to 108.9 %. In combination with sample enrichment by two-step LLE extraction, this is the first CE study conducted to determine phenols in the EPA list using two detector approaches, specifically CE-LEDIF/CE-UV.

Fifteen perfluorinated compounds, including perfluorocarboxylic acids and perfluoroalkyl sulfonate salts (with 4 to 12 carbon atoms in their structure) in Eichhornia crassipes (Mart.) Solms samples underwent analysis using Liquid Chromatography- tandem Mass Spectrometry (LC-MS/MS). This analysis was conducted alongside sample preparation employing ultrasound-assisted extraction and solid-phase extraction. The optimization of solvent extraction involved the use of 5 ml of methyl tert-butyl ether (MTBE), 10 minutes of sonication, and three repeated extraction cycles. The weak anion exchange (WAX) cartridge was selected after evaluating and comparing the solid-phase extraction efficiencies of both WAX and C18 cartridges. The evaluated method demonstrated successful analysis of all 15 PFCs in plant samples, achieving favorable recoveries ranging from 71 to 116% (with a coefficient of variation of 1.2-6.6%). The quantification limits for these 15 PFCs in Eichhornia crassipes (Mart.) Solms samples ranged between 0.30 to 0.54 ng/g. ® 2023 Journal of Science and Technology - NTTU

Bioaccessibility of halogenated flame retardants (HFRs) and organophosphorus esters (OPEs) is necessarily investigated to provide more accurate risk assessment and information about absorption behavior of these pollutants. In this study, total and bioaccessible concentrations of HFRs (including legacy and alternative substances) and OPEs were determined in settled dust samples collected from Vietnamese e-waste and end-of-life vehicle (ELV) processing areas. Concentrations of both HFRs and OPEs were significantly higher in the e-waste dust than ELV dust. Bioavailability of HFRs and OPEs in dust was determined by using an in vitro assay with human-simulated digestive fluids, dialysis membrane, and Tenax® TA sorptive sink. Bioaccessibility of HFRs was markedly lower than that of OPEs, which could be largely due to higher hydrophobicity of HFRs compared to OPEs. Bioaccessibility of almost hydrophobic compounds were markedly lower in the e-waste dust (containing micronized plastic debris) than in the ELV dust (containing oily materials), suggesting the influence of specific dust matrices on pollutant bioaccessibility. Although the daily uptake doses of selected HFRs and OPEs from dust were markedly higher in the e-waste sites compared to the ELV sites, the direct exposure risk was not significant. Our results suggest that bioaccessibility can partly explain the differences between dust and uptake profiles, which may relate to accumulation profiles of HFRs and OPEs in human samples.

Millions of people worldwide are exposed to arsenic (As) contaminated groundwater. Despite decades of research and evidence of As mobilisation in anoxic aquifers being caused by reductive dissolution of iron minerals, the mechanisms behind the local scale variability of dissolved As remains unclear. Therefore, the trans-disciplinary AdvectAs project investigates the environmental behaviour and spatial heterogeneity of dissolved As in groundwater in the Red River delta, Vietnam. Here we present the results from hydrochemical and water isotope investigations. In particular, we will show how the large As variability (0.1–510 µg/L) is related to consecutive As (im)mobilisation steps, depending on site hydrology, geology and the interplay of Fe, Mn, S and organic matter cycles. Such complexity of (im)mobilisation processes can be simplified in 5 major hydro(geo)chemical zones, providing a conceptual tool with potential for application at other sites in Asia affected by geogenic As contamination of groundwater.

Compost stability is a significant quality indicator that needs to be determined before using compost as an organic fertiliser. In this work, a novel device for assessing compost stability based on the oxygen consumption (OC) method was successfully developed. The design of this prototype was created to effectively solve inherent limitations observed in commercially available equipment functioning on the same concept (Oxitop devices). The performance of the device was evaluated in the laboratory to determine the OC of two different types of compost samples (food waste and green compost). The data indicated that the device worked stably and accurately during the test. Between the two types of samples, the compost based on food waste had higher AT4 and OCmax values but with lower K values. According to the EU regulations, both types of samples were considered stable.

This study was conducted in 2020-2021 to investigate several epidemiological factors and parents' knowledge of antibiotic use in children in Thai Nguyen and Ha Giang. Methods: 459 eligible subjects were investigated for epidemiological information and knowledge of antibiotic use. 275 bacterial culture were successfully done from nasopharyl swabs of participants. Results: Some epidemiological factors such as parents' smoking, a high percentage of pipe tobacco smoking (21.6%), and up to 30.7% of relatives living in the same house (including Ha Giang at 31.4% and Thai Nguyen at 30.0%). In children, medical history of tonsillitis accounted for 37.3%, with otitis media accounting for 11.5%. The average influenza incidence was 1.7 times per year in Ha Giang and 1.9 times per year in Thai Nguyen. The proportion of children with antibiotic consumption over the past year was 47.3% in Thai Nguyen and 34.7% in Ha Giang. Commonly used antibiotics were amoxicillin and cephalexin, and most parents did not remember or knew the names of the antibiotics their children were taking. There were 42.0% of parents who knew about the use of antibiotics that the effects of antibiotics could treat bacteria. This rate was 46.9% in Ha Giang and 36.8% in Thai Nguyen, both statistical significance with p< 0.05. Of those 275 bacterial culture from nasopharyl swab, 78 (28.4%) was detected S. pneumoniae, which concordance with previous literature review. Recommendations: Conduct communication and education programs to better understand the use of antibiotics and reduce risk factors for respiratory infections. Further investigation, intervention may needed to reduce risk in S. pneumoniae carriers.

Background Xuan Lien Nature Reserve was established in 1999 to protect important habitats and wildlife in the northern part of the Annamites in Vietnam. While Xuan Lien is home to many threatened species, it has experienced a high level of human disturbance over the last decades. To document and provide baseline data on the status and distribution of the terrestrial vertebrate fauna community in the region, we conducted a systematic camera trapping survey in Xuan Lien Nature Reserve in 2023. The data collected during the survey will help design proper conservation measures to better conserve the remaining species. New information Our study investigates and updates the species richness of mid- to large-sized terrestrial vertebrates, thus providing essential information for developing conservation strategies in Xuan Lien Nature Reserve, Vietnam. As camera traps were set up in a grid-based design, our survey also generated the first-ever systematic data for terrestrial vertebrate fauna in the area. The study covers approximately 21,000 hectares (about 77% of the area), using 35 camera trap stations; each station consists of two cameras. In total, the final dataset consists of 6,276 trap nights, recording at least 46 species in 39 genera. The results suggest that Xuan Lien is a key stronghold for small carnivores, based on the diversity of such species groups in the Reserve. We failed to detect the previously documented Roosevelt's muntjac ( Muntiacus rooseveltorum Osgood, 1932) and we only documented a single record of the northern red muntjac ( Muntiacus vaginalis Boddaert, 1785). Our survey confirms the severity of overhunting and other anthropogenic threats to the mammal fauna, especially ungulates, in the Reserve.

Although Eichhornia crassipes, commonly known as water hyacinth, has been widely used in wastewater treatment, further investigations are still needed to explore the removal efficiency of perfluoroalkyl acids (PFAAs) from the aqueous environment using this floating aquatic plant. In this study, a hydroponic experiment was conducted to assess accumulation, bioconcentration factors (BCFs), translocation factors (TFs), and removal rates of eight PFAAs by water hyacinth. The obtained results indicated that all PFAAs, including five perfluoroalkyl carboxylic acids (PFCAs) with chain lengths C4-C8 and three perfluoroalkyl sulfonic acids (PFSAs) with C4, C6, and C8, were readily accumulated in water hyacinth. Throughout the duration of the experiment, there was a noticeable increase in PFAA concentrations and BCF values for different plant parts. For the root, PFAAs with more carbon numbers showed a higher uptake than the shorter homologues, with PFSAs being more readily accumulated compared to PFCAs with the same carbon number in the molecules. In contrast, the levels of long-chain PFAAs were comparatively lower than those of short-chain substances in the stem and leaf. Notably, PFAAs with less carbon numbers, like PFPeA, PFBA, and PFBS, showed a remarkable translocation from the root to the stem and leaf with TFs >1. For the whole plant, no significant correlation was found between BCFs and organic carbon-water partition coefficients (K-oc), octanol-water partition coefficients (K-ow), membrane-water distribution coefficients (D-mw), or protein-water distribution coefficients (D-pw). The removal rates of PFAAs ranged from 40.3 to 63.5 % throughout the three weeks of the experiment while the removal efficiencies varied from 48.9 % for PFHxS to 82.6 % for PFPeA in the last week.

The paddy soils were collected in the rice growing fields and the uncultivated lands around the Nam Son domestic waste landfill in Hanoi. The average concentration of 16 US EPA priority PAHs in dry soil was 61.61 ng/g, with a range of 22.15-115.1 ng/g. The higher levels of PAHs in soil samples were observed in cultivated paddy fields near the landfill in comparison with the fields far from the landfill. On the other hand, there was no difference in PAHs levels in cultivated paddy fields near the landfill and along the irrigation water canal. Concentrations of 16 PAHs in paddy soils decreased in the order: 5 rings > 3 rings > 4 rings > 2 rings > 6 rings in this area. The PAH isomeric diagnostic ratios including Fluth/(Fluth+Pyr) ratio (Ave 0.43, a range of 0.17-0.61), BaA/(BaA+Chr) ratio (Ave 0.51, a range of 0.26-0.63), IcdP/(IcdP+BghiP) ratio (Ave 0.71, a range of 0.51-0.90) indicated that the potential main sources emitted PAHs in paddy soils from pyrogenic biomass combustion and coal burning. Compared with the risk threshold causing adverse impacts on the ecological environment from different countries in the world, concentrations of PAHs in the soil surrounding the Nam Son landfill area were still below the affected limit. However, environmental quality around the landfill area still needs to be regularly monitored to take timely measures to protect the environment in this area.

Although the world witnesses a significant increase in international trade, it also faces two serious externalities, namely environmental pollution, and income inequality. The world urgently needs to deal with these three socials, economic, and environmental issues effectively to achieve sustainable and harmonious development. However, the link between income distribution, international trade, and environmental quality has not received much attention in the existing literature. This paper uses a sample of 94 countries from 1966 to 2015 to examine the complementary effects of income disparity and trade openness on carbon dioxide emissions. The results give qualified support for the beneficial impacts of higher income inequality and trade openness on reducing carbon dioxide emissions. However, these benefits are obtained only at a low level of trade openness and income disparity, respectively. Given a high level of international trade and an increasing trend of income inequality, the governments should focus on ensuring a fairer income distribution while adopting stricter friendly environmental policies to minimize their environmental damages.