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3,4-methylenedioxymethamphetamine (MDMA) or publicly known as "ecstasy" is a drug abuse substance. Since antibodies that detect MDMA typically also recognize its chemical analogue, methamphetamine (METH), we identified antibodies specifically recognizing MDMA, but not METH, named 1bB11 and 1bF12, using phage display. The crystal structure of 1bB11 in complex with MDMA was determined at 3.2 Å resolution. Key interactions were found between the epoxide moiety of MDMA and S34 and Y36 of the light chain. Additional interaction with E33 of the heavy chain contributes to anchoring MDMA. Mutagenesis-based biochemical analysis confirmed the importance of these residues in MDMA binding. Comparing the structure of 1bB11 to a scFv6H4, which binds both METH and MDMA, revealed opposite binding orientations. Taken together, our data provides a structural framework for selective binding to MDMA by the 1bB11 antibody, paving a way to develop a highly specific antibody for diagnosis., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Geonho Cheon, Dahyun Hwang, Truc Chi Le and Sangho Lee have patent #10-2022-0184221 pending to Sungkyunkwan University. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Low-cost sensors (LCS) network is widely used to improve the resolution of spatial-temporal distribution of air pollutant concentrations in urban areas. However, studies on air pollution sources contribution to the microenvironment, especially in industrial and mix-used housing areas, still need to be completed. This study investigated the spatial-temporal distribution and source contributions of PM 2.5 in the urban area based on 6-month of the LCS network datasets. The Artificial Neural Network (ANN) was used to calibrate the measured PM 2.5 by the LCS network. The calibrated PM 2.5 were shown to agree with reference PM 2.5 measured by the BAM-1020 with R 2 of 0.85, MNE of 30.91%, and RMSE of 3.73 μg/m 3 , which meet the criteria for hotspot identification and personal exposure study purposes. The Kriging method was further used to establish the spatial-temporal distribution of PM 2.5 concentrations in the urban area. Results showed that the highest average PM 2.5 concentration occurred during autumn and winter due to monsoon and topographic effects. From a diurnal perspective, the highest level of PM 2.5 concentration was observed during the daytime due to heavy traffic emissions and industrial production. Based on the present ANN-based microenvironment source contribution assessment model, temples, fried chicken shops, traffic emissions in shopping and residential zones, and industrial activities such as the mechanical manufacturing and precision metal machining were identified as the sources of PM 2.5 . The numerical algorithm coupled with the LCS network presented in this study is a practical framework for PM 2.5 hotspots and source identification, aiding decision-makers in reducing atmospheric PM 2.5 concentrations and formulating regional air pollution control strategies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Inc.)

This study assessed the machine learning based sensitivity analysis coupled with source-apportionment of volatile organic carbons (VOCs) to look into new insights of O 3 pollution in Yunlin County located in central-west region of Taiwan. One-year (Jan 1 to Dec 31, 2021) hourly mass concentrations data of 54 VOCs, NO X , and O 3 from 10 photochemical assessment monitoring stations (PAMs) in and around the Yunlin County were analyzed. The novelty of the study lies in the utilization of artificial neural network (ANN) to evaluate the contribution of VOCs sources in O 3 pollution in the region. Firstly, the station specific source-apportionment of VOCs were carried out using positive matrix factorization (PMF)-resolving six sources viz. AAM: aged air mass, CM: chemical manufacturing, IC: Industrial combustion, PP: petrochemical plants, SU: solvent use and VE: vehicular emissions. AAM, SU, and VE constituted cumulatively more than 65% of the total emission of VOCs across all 10 PAMs. Diurnal and spatial variability of source-segregated VOCs showed large variations across 10 PAMs, suggesting for distinctly different impact of contributing sources, photo-chemical reactivity, and/or dispersion due to land-sea breezes at the monitoring stations. Secondly, to understand the contribution of controllable factors governing the O 3 pollution, the output of VOCs source-contributions from PMF model along with mass concentrations of NO X were standardized and first time used as input variables to ANN, a supervised machine learning algorithm. ANN analysis revealed following order of sensitivity in factors governing the O 3 pollution: VOCs from IC > AAM > VE ≈ CM ≈ SU > PP ≈ NO X . The results indicated that VOCs associated with IC (VOCs-IC) being the most sensitive factor which need to be regulated more efficiently to quickly mitigate the O 3 pollution across the Yunlin County., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The Mekong River Delta in Vietnam, is concerned by numerous microplastic-related issues such as a lack of wastewater treatment facilities and mismanagement of plastic waste released from agriculture, aquaculture and related activities. This study aimed to examine the presence of microplastics in surface water and sediment by collecting samples from six sites along the Tien River and its distributaries in February 2019. The results showed that the average concentration of microplastics over the entire area was 53.8 ± 140.7 items m -3 in surface water and 6.0 ± 2.0 items g -1 dried weight in sediment, with a predominance of microplastic fibres rather than fragments, respectively 85 % and 98 % in surface water and sediment. In the main flow of surface water, the concentration of microplastics was stable; however, in the sediment, microplastic concentration was affected by the high dynamic flow regime rather than the sources where microplastics are released., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Microplastic fibres are the most abundant microplastics in waterways worldwide. The settling of fibres is distinct from other particles because of their aspect ratio and shape. In this paper, we test the hypothesis that length, curliness, and settling orientation control the settling velocity of microplastic fibres in a suite of laboratory experiments. Using a Particle Tracking Velocimetry method, we measured the settling velocity of 683 polyester microplastic fibres of 1 to 4 mm in length. Experimental findings support our hypothesis that for microplastic fibre longer than 1 mm, changing settling orientation from horizontal to vertical can increase 1.7 times the settling velocity. Fibre curliness can significantly reduce the settling velocity, where a curly fibre 1.3 times longer than a straight fibre can settle 1.75 times slower. In contrast, short microplastic fibres (less than 1 mm) mostly settle horizontally, and their settling velocity is unaffected by curliness. The drag force exerting on settling microplastic fibres was analysed, and the sphere-equivalent diameter was found to be a good representation of microplastic fibre size to predict the drag coefficient. Measured settling velocity ranges between 0.1 and 0.55 mm/s and exhibits a slight increase with the increasing length of the fibres. This low-velocity range raises concerns that microplastic fibres can favour biological flocculation, form clustered aggregates with microorganisms, feed aquatic organisms and cause bioaccumulation at higher trophic levels., Competing Interests: Declaration of competing interest The author declares that there are no competing interests., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Anthropogenic fibres are an emerging pollutant worldwide. The Can Gio mangrove area is located downstream of the Saigon River, and is characterised by high level of anthropogenic fibres originating from domestic and industrial textile and apparel manufacturing. In this area, biota is thus subjected to a high potential risk of anthropogenic fibre contamination. This study aims to characterise the accumulation of anthropogenic fibres in different tissues, i.e. gills, digestive systems, and remaining tissues, of white clams (Meretrix lyrata) cultivated in the Can Gio beach sand, during a seven-month sampling period. The results showed an average concentration of 3.6 ± 2.1 fibres individual -1 or 2.7 ± 2.4 fibres g -1 ww. Higher fibre accumulation was observed in remaining tissues than in gills and digestive systems, and no temporal variation was observed in all clam tissues. The intake of fibres by humans consuming clams was estimated to be 324 fibres inhabitant -1  yr -1 ., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Antimalarial agents used as monotherapy are increasingly ineffective due to the emergence of Plasmodium resistant strains. Artemisinin (Arte), extracted from Artemisia annua, presents a good efficiency against the Plasmodium strains and is currently used to treat malaria. To avoid the appearance of new resistant strains to artemisinin, the use of Artemisinin-based Combination Therapy (ACT) with another antimalaria agent was recommended by WHO to provide an effective cure and delayed resistance. Although combined formulations of various drugs with Artemisinin have been developed, their release is immediate, and they require multiple doses with side detrimental effects and effectiveness still desired. To improve its efficiency, controlled release formulations were developed to ensure long-term antiplasmodial activity by associating Artemisinin with a natural antimalarial agent extracted from Peschiera fuchsiaefolia (Pf). The Pf extract (containing mostly low soluble alkaloids) was complexed with carboxymethylcellulose to improve its solubility and stability. Two formulation types are reported. As bilayer tablet dosage form, the kinetic release pattern was an immediate release of Artemisinin, followed by a slow sustained release of Pf for 12 h. As monolithic tablet, the release profile shows a simultaneous sustained release of the two active agents, about of 10 h for Arte and 12 h for Pf., (Copyright © 2020 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.)

In aquatic environments, assessment of microplastic concentrations is increasing worldwide but environments from developing countries remain under-evaluated. Due to disparities of facilities, financial resources and human resources between countries, protocols of sampling, analysis and observations used in developed countries cannot be fully adapted in developing ones, and required specific adaptations. In Viet Nam, an adapted methodology was developed and commonly adopted by local researchers to implement a microplastic monitoring in sediments and surface waters of 21 environments (rivers, lakes, bays, beaches) of eight cities or provinces. Microplastic concentrations in surface waters varied from 0.35 to 2522 items m-3, with the lowest concentrations recorded in the bays and the highest in the rivers. Fibers dominated over fragments in most environments (from 47% to 97%). The microplastic concentrations were related to the anthropogenic pressure on the environment, pointing out the necessity in a near future to identify the local sources of microplastics., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

The purpose of this investigation was to elaborate a fast zymographic assay of oxidase enzymes in the presence of interfering enzymes as catalase (which disturbs current dosages based on H 2 O 2 detection). This method also allows the determination of intrinsic specific activity (ISA) of oxidases, such as diamine oxidase (DAO) or glucose oxidase (GOD). The SDS-PAGE gels with entrapped peroxidase have been obtained by polymerization of acrylamide and bis-acrylamide in the presence of horse-radish peroxidase. The entrapped peroxidase was uniformly distributed in the PolyacrylAmide (PAA) material and did not migrate during electrophoresis. The obtained PAA gels allow the electrophoretic separation of various oxidases from contaminating proteins. As an example, to reveal DAO, the resulting PAA-gel should be incubated after the electrophoretic run in the developing solution containing putrescine (a DAO substrate) and o-phenylenediamine (a HRP substrate) to give coloured bands on the gel in the presence of DAO-generated H 2 O 2 . The results showed that is possible to determine the DAO in the presence of interfering catalase because they migrate differently. Thus, the H 2 O 2 released in situ by DAO is no more decomposed by catalase because of its different mobility. It was also found that the same electrophoretic gel, after zymography, can be restained by Coomassie Blue for quantitation of proteins corresponding to the zymographic bands. With the obtained enzyme units and protein concentration it is also possible to calculate the intrinsic specific activity of DAO directly from the intensities of enzyme bands in zymography and from those of protein bands (Coomassie Blue staining), quantified by densitometry., (Copyright © 2017 Elsevier B.V. All rights reserved.)