Vietnam is a Southeast Asian developing country with rapidly increasing air pollution, especially in large cities. Over 350,000 chemicals and chemical mixtures are produced and used in Vietnam; ...however, the country has only implemented air quality standards for 44 substances, which are primarily focused on inorganic and volatile organic compounds. Although numerous pesticides are frequently applied across large cities in Vietnam, information on their concentrations in atmospheric particulate matter (APM) is limited. Therefore, to investigate their occurrence and health effects, 187 pesticides in APM were screened using the liquid chromatography-mass spectrometry-quadrupole time of flight- Sequential Window Acquisition of All Theoretical Fragment Ion Spectra method (LC-QTOF-MS-SWATH). A total of 22 pesticides (16 fungicides and 6 herbicides) were quantified in the dry and rainy seasons. Among them, 19 substances were quantified in APM for the first time in Vietnam. Their median total concentrations in the dry season were higher than those in the rainy season, and the concentrations in the daytime were one-third of the night-time concentrations in both seasons. Their total levels ranged from 0.82 to 21.1 ng m−3 (median, 3.63 ng m−3), the detection frequencies of 9 pesticides were higher than 70%, and 7–14 pesticides were detected per sample (median, 10). Some of the detected pesticides were likely sourced from their prevalent use in amenity turf protection (e.g., in parks and public roads) and weed control (e.g., in gardens, floriculture, and agriculture). The total daily intake (DIair) values for adults, children, and infants were 8.17E-06, 2.06E-05, and 2.45E-05 mg kg−1 d−1, respectively, and the highest Hazard Quotients (HQs) were 4.81E-04, 1.22E-03, and 1.44E-03, respectively. All HQs and HIs of the pesticides were < 1 for all population groups (adults, children, and infants), indicating negligible exposure risks.
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•LC-QTOF-MS-SWATH used to screen 187 pesticides in atmospheric particulate matter.•Nineteen pesticides in atmospheric particles detected for the first time in Vietnam.•Pesticide concentrations ranged from 0.82 to 21.1 ng m−3.•Nine pesticides had detection frequencies of >70%.•HI and DIair were <1; human risks from atmospheric pesticides were negligible.
Air pollution is the most serious environmental issue in Vietnam, particularly in big cities. Air pollutants that are set as environmental standards are regularly monitored by the public ...institutions. Whereas, environmental data on organic micro-pollutants in atmospheric particulate matters (APMs) is limited, including PAHs and POPs. Although massive pesticides are used in big cities, their data in APMs in Vietnam is very scarce. In order to elucidate their occurrence in the ambient air in Hanoi and their health effects, we surveyed 107 insecticides in APMs by a novel target screening method using LC-QTOF-MS-SWATH. A total of 19 insecticides were detected in the dry and the rainy seasons. Among them, 16 substances are, to our knowledge, reported for the first time in the literature. Their total concentrations varied from 0.47 to 27.0 ng m−3 (median, 3.6 ng m−3), detection frequencies of 12 compounds are higher than 42%, and the number of insecticides detected per each sample ranging from 5 to 13 (median, 9). Total concentrations in the dry season were generally higher than in the rainy season, and concentrations at night were higher than daytime in both seasons. The level of insecticides depends not only on the season, but also on its physicochemical properties, its application conditions, and the meteorological conditions. Their emission sources could be related to agricultural usage, floricultural activities, and pest control in houses. The total maximum daily intake (DIair) through inhalation for adults and children were 2.39E-05 mg kg−1 d−1 and 2.98E-05 mg kg−1 d−1, respectively. The highest Hazard Quotients (HQs) were 1.34E-03 and 3.37E-03, and the highest Hazard Indices (HIs) were 2.71E-03 and 6.33E-03 for adults and children, respectively. All values of HQs, and HIs of insecticides were less than 1, indicating that health risk would be negligible.
•This is the first study using LC-QTOF-MS-SWATH to monitor insecticides in APMs.•Sixteen out of 19 insecticides detected in APMs were firstly found in Vietnam.•There are no seasonal differences of the average insecticide concentrations in APMs.•Inhalation risk assessment of insecticides for adults and children was negligible.
The article proposes an intelligent controller for output regulation of nonlinear non-autonomous continuous-time systems with mismatched uncertainties and matched disturbances. This controller is ...established by firstly converting the original system into an input-to-state stable one via learning-based compensation of lumped system disturbances and then applying the standard P-type iterative learning control. The learning-based disturbance compensator is basically created with the numerical backward differentiation in iterative mode. The control performance of the obtained sampled data system using the proposed controller has been verified throughout both in theory and comparison with the existing method via numerical simulations.
This work focuses on the degradation mechanism and self-cleaning ability of acrylic/A-TiO2 nanocomposite coating.
In the study of photocatalytic degradation, Infrared spectroscopy (I.R.) data ...indicated that both the losses of alkane C.H. group, the weight and transparency of nanocomposite coating increased with increasing the nanoparticle content. To explain this finding, we proposed a new degradation mechanism for this water-based acrylic/A-TiO2 nanocomposite coating.
The experimental data confirmed a high self-cleaning ability of the as-prepared coating to remove both methyl blue and artificially dirt mixtures for the self-cleaning test. As observed, methyl blue content has been degraded after 12 h of U.V. exposure. Furthermore, when used this nanocomposite coating as a topcoat in the Solar heat reflectance (SHR) coating system, after 48 h of U.V. exposure, the heat reflectance of the SHR coating system was highly recovered from 59% to 76%, due to the self-cleaning activity of nano-topcoat. Whereas, without topcoats, the heat reflectance of SHR coating was weakly retrieved from 57% to 61%.
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•Nano-A-TiO2 inhibited the transformation of chemical structure and weight loss of acrylic coating.•New degradation mechanism of acrylic polymer/A-TiO2 nanocoating was proposed.•Nanocoating significantly recovered the heat reflectance of solar heat reflective system.
Abstract
Current WHO-recommended diagnostic tools for tuberculosis infection (TBI) have well-known limitations and viable alternatives are urgently needed. We compared the diagnostic performance and ...accuracy of the novel QIAreach QuantiFERON-TB assay (QIAreach; index) to the QuantiFERON-TB Gold Plus assay (QFT-Plus; reference). The sample included 261 adults (≥ 18 years) recruited at community-based TB case finding events. Of these, 226 underwent Tuberculin Skin Tests and 200 returned for interpretation (TST; comparator). QIAreach processing and TST reading were completed at lower-level healthcare facilities. We conducted matched-pair comparisons for QIAreach and TST with QFT-Plus, calculated sensitivity, specificity and area under a receiver-operating characteristic curve (AUC), and analyzed concordant-/discordant-pair interferon-gamma (IFN-γ) levels. QIAreach sensitivity and specificity were 98.5% and 72.3%, respectively, for an AUC of 0.85. TST sensitivity (53.2%) at a 5 mm induration threshold was significantly below QIAreach, while specificity (82.4%) was statistically equivalent. The corrected mean IFN-γ level of 0.08 IU/ml and corresponding empirical threshold (0.05) of false-positive QIAreach results were significantly lower than the manufacturer-recommended QFT-Plus threshold (≥ 0.35 IU/ml). Despite QIAreach’s higher sensitivity at equivalent specificity to TST, the high number of false positive results and low specificity limit its utility and highlight the continued need to expand the diagnostic toolkit for TBI.
Periodic mesoporous organosilica (PMO) materials have attracted considerable attention as promising nanocarriers to improve the therapeutic efficacy of anticancer drugs. Herein, a new type of ...biodegradable disulfide-based PMO was synthesized by incorporating disulfide linkers into the silica framework of nanoparticles (NPs). The homogeneous spherical morphology with an average size of 50 nm is observed by scanning electron microscope, transmission electron microscopy. Furthermore, the physicochemical characterizations were also performed by using Fourier transform infrared spectra and X-ray photoelectron spectroscopy confirmed the presence of disulfide in the structure of NPs. It is notable that the disulfide moieties incorporated into the structure of NPs lead to fast degradation, within 5 days to complete degradation. Paclitaxel (PTX), a hydrophobic anticancer drug, was loaded into the porous particles with a high loading capacity up to 602 mg.g−1. A large amount of PTX was released at the early stage of the release process in the phosphate buffer saline solution containing reduced glutathione and then released slowly at a steady rate. The effective cellular uptake of NPs into malignant cells and normal cells also demonstrated. PTX-loaded NPs exhibited higher anticancer activity against cancer cells as compared to free PTX, indicating the potential nanocarrier for cancer therapy.
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•Novel biodegradable disulfide-based nanoparticles were successfully synthesized.•The synthesized nanoparticles have small size with an average size of 50 nm.•Hydrophobic paclitaxel was loaded into nanoparticles with high loading capacity up to 602 mg.g−1.•Release profiles demonstrated the enhance of solubility of poor soluble paclitaxel.•Paclitaxel-loaded NPs exhibited higher anticancer activity against cancer cells as compared to free paclitaxel.
Pharmaceutical and personal care products (PCPPs) were recently recognized as emerging pollutants due to their potential for adverse health and environmental impacts. One potential route of exposure, ...atmospheric particulate matter (APM), for polar PPCP chemicals has to date received limited attention. This study screened for 190 polar PPCP chemicals in outdoor APM samples collected from two locations in Hanoi, Vietnam, and predictions of source and potential effects on human health are presented. Day and night, as well as dry and rainy seasonal samples, were taken, and samples screened by LC-TOF, using sequential window acquisition and all theoretical fragment ion spectra method. Eleven PPCP chemicals were detected above the LOD and in more than one sample. The ∑11PPCP chemicals ranged from 0.61 to 21.9 ng m
−3
(median 2.07 ng m
−3
), with between 2 and 6 compounds identified in individual samples (median 4). The ∑11PPCP chemicals collected near a heavy traffic area was greater than that in a populated residential zone. Night concentrations were significantly greater than day in both dry and rainy seasons (
p
< 0.05). Butyl methoxydibenzoylmethane, benzophenone-3, acetaminophen, cotinine, and fluorescent brightener 71 were detected in > 50% of samples. These are typically found in sunscreens, cosmetics, antipyretics, tobacco, and dyes. The DI
air
, hazard quotient (HQ), and hazard index (HI) for adults and children at sampling sites were estimated. The HQ for both adults and children were orders of magnitude less than the risk or were close to or whichever. APM does appear to be a potential additional secondary exposure source of PPCP chemicals to the environment and more work is needed to identify if sources are local or ubiquitous and if there is a greater health risk.
The employment of a purpose-made capillary electrophoresis (CE) instrument with capacitively coupled contactless conductivity detection (C4D) as a simple and cost-effective solution for clinical ...screening of paraquat in plasma samples for early-stage diagnosis of acute herbicide poisoning is reported. Paraquat was determined using an electrolyte composed of 10mM histidine adjusted to pH 4 with acetic acid. A detection limit of 0.5mg/L was achieved. Good agreement between results from CE-C4D and the confirmation method (HPLC-UV) was obtained, with relative errors for the two pairs of data better than 20% for 31 samples taken from paraquat-intoxicated patients. The results were used by medical doctors for identification and prognosis of acute paraquat poisoning cases. The objective of the work is the deployment of the developed approach in rural areas in Vietnam as a low-cost solution to reduce the mortality rate due to accidental or suicidal ingestion of paraquat.
This article investigates the effect of academic majors on entrepreneurial intentions of engineering and business students. The research model was established based on the extension of the theory of ...planned behavior (TPB) through combining the TPB model, perceived risks, academic majors and personalities of students. A sample of 1844 students from the four largest universities in engineering and business in Vietnam were surveyed. The main findings indicated that (i) the relationship in the TPB model was accepted except the effect of subjective norms on entrepreneurial intentions; (ii) perceived risks have negative impacts on perceived behavioral control; (iii) male engineering students have a higher entrepreneurial intentions than female students, but this result was not found in business students; (iv) engineering students have a higher entrepreneurial intentions than business students; (vi) there are no differences between the entrepreneurial intention of students coming from rural and urban areas. The study also contributes to some policy discussion to extend the current debate about the role of academic majors that students take in university in the entrepreneurial process as well as the importance of entrepreneurial students to society.
Academic majors, business students, engineering students, entrepreneurial intentions, theory of planned behavior.
Case 1 tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative organism of coronavirus disease 2019 (COVID-19), on Jan 30, 2020, and remained in isolation ...until recovery. Screening of 79 individuals who had been in contact with these two patients (namely, family members in the same household and anyone who had been within 2 m of them) was initiated on Jan 31. On Feb 8, 2020, increased contact investigation was commenced among an additional 343 contacts of the people returning from China and the secondary cases diagnosed in Vinh Phuc, with screening of contacts of any suspected cases, and health workers providing direct medical care.
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