High Persistence Research Articles

Use of non-linear multiple regression models for setting water quality criteria for copper: Consider the effects of salinity and dissolved organic carbon

Cu pollution is a global concern because of its high toxicity and persistence. Few investigations have been conducted on the effects of salinity and dissolved organic carbon (DOC) on Cu toxicity and water quality criteria (WQC). To analyze their impact on the WQC of Cu, non-linear multiple regression (NLMR) models based on salinity and DOC were constructed. The NLMR models demonstrated that when salinity increased, the toxicity values for Cu on fish, mollusca, rotifer, and echinodermata first increased and then declined, whereas those for arthropoda and algae increased. These findings demonstrate that salinity has a substantial impact on Cu toxicity, primarily owing to changes in physiological activity. The original and corrected WQC values in the upper, middle, and outer regions of the Yangtze Estuary were derived based on the species sensitivity distribution method. These values were 1.49, 3.49, 8.86, and 0.87 μg·L−1. An important finding was that lower Cu concentrations in the outer areas posed the highest ecological risk owing to the effects of salinity and DOC. NLMR models are applicable to other coastal areas worldwide. This provides valuable information for the establishment of an accurate and protective estuary for Cu-related WQC.

Dynamics of SARS-CoV-2 Spike-IgG throughout Three COVID-19 Vaccination Regimens: A 21-Month Longitudinal Study of 82 Norwegian Healthcare Workers

To facilitate interpretation of clinical SARS-CoV-2 anti-spike IgG analyses post-vaccination, 82 healthcare workers were followed through three vaccination-regimens: two regimens were comprised of two doses of BNT162b2 three or six weeks apart, followed by a dose of mRNA-vaccine, and in the other regimen, the first dose was replaced by ChAdOx1 nCov-19. After each dose, anti-spike IgG was compared between regimens. As many participants became infected, anti-spike IgG persistence was compared between infected and uninfected participants. Thirteen to twenty-one days after the first dose, seroconversion, and the median anti-spike IgG level in the ChAdOx1 group was significantly lower than in the BNT162b2 groups (23 versus 68 and 73 AU/mL). The second dose caused a significant increase in anti-spike IgG, but the median level was lower in the BNT162b2-short-interval group (280 AU/mL), compared to the BNT162b2-long-interval (1075 AU/mL) and ChAdOx1 (1160 AU/mL) group. After the third dose, all groups showed increases to similar anti-spike IgG levels (2075-2390 AU/mL). Over the next half year, anti-spike IgG levels declined significantly in all groups, but appeared to persist longer after post-vaccination infection. This is the first three-dose study with one dose of ChAdOx1. Despite initial differences, all vaccine regimens gave similarly high antibody levels and persistence after the third dose.

PFAS Characteristics and Treatment for Landfill Leachate

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are manmade chemicals which has been extensively used, resulting in great potential for human and environmental accumulation due to high persistence. PFASs can be divided to two parts, terminal and precursor compounds, based on how many fluorine atoms link to the carbon bonds. Many studies have examined the removal ability of method including activated carbon (AC), Foam fractionation (FF), chemical oxidation and boron-doped diamond anodes (BBD). This paper focus on introducing advanced remedial technology for PFAS treatment from landfill leachate. The details about PFASs are introduced, including the chemical structure, source, and properties. Then, different types of PFASs from landfill leachate are demonstrated. Some of PFAS, especially short-chain, are prone to stay as liquid phase. Activated carbon, a great model of adsorption, shows excellent performance on removal of PFOS and PFOA. In addition, boron-doped diamond anodes technique which belongs to the electrochemical anodic oxidation, have a great potential on landfill leachate in the future. Last but not least, the conclusion makes a summary and shows possible treatment to landfill in the future.

Target and suspect screening of pesticide residues in soil samples from peach orchards using liquid chromatography quadrupole time-of-flight mass spectrometry

Agricultural soil contamination by pesticide residues has become a serious issue of increasing concern due to their high persistence and toxicity to non-target species. However, as the world’s largest peach producer, national scale surveys on pesticide residues in peach orchard soils are scarce in China. In this study, a target and suspect screening method covering over 200 pesticides commonly used in peach orchards was developed using ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry in MSE. An identification strategy using different data processing parameters was developed to identify the pesticide occurrence in soil. The method was applied to soil samples from typical peach orchards in 12 regions across China. The present work also discusses in detail the frequency of occurrence, concentration of pesticides, spatial distribution of multiresidues, and relationship between pesticide occurrence and soil properties. In the tested soil samples, 21 herbicides (level 1), 31 fungicides (level 2a), 24 insecticides (level 2a), and 3 growth regulators (level 2a) were identified. The total concentrations of quantifiable herbicides in the soil samples ranged from 1.05 to 327 ng/g. Only in 5.4% of the soil samples, no pesticide residues were present. By contrast, more than 86% of the total contained multiple residues. This study represents the first large-scale survey of pesticides in soil from peach orchards and provides comprehensive and accurate information on the pesticide residue status for risk assessment.

Bye bye Ms. American Sci: Women and the leaky STEM pipeline

More than two-thirds of STEM jobs are held by men. In this paper, I provide a detailed analysis of the STEM pipeline from high school to mid-career in the United States, decomposing the gender gap in STEM into six stages. Women are lost from STEM before college, during college, and after college. Men are more likely to be STEM-ready before college, scoring higher on science tests and having taken more advanced math and science courses. This accounts for 35% of the overall gender gap in STEM careers. During college, men are far more likely than women to start in a STEM major, accounting for 26% of the gap. After college, male STEM graduates are more likely to enter STEM jobs, accounting for 41%. Men’s higher persistence in STEM majors is a smaller factor, while women attend college at higher rates than men, which works to reduce the final gender gap in STEM. The results show that there is no single stage to focus on in understanding the gender gap in STEM.

The discovery of human Plasmodium among domestic animals in West Sumba and Fakfak, Indonesia

Background: In Indonesia, malaria incidence is at a high rate despite maximum preventive efforts. Therefore, this study aims to determine the possibility of a Plasmodium reservoir among domestic animals in malaria-endemic areas. Methods: Animal blood was collected using EDTA tubes, then smeared and stained with Giemsa for Plasmodium microscopic identification. About 10 µl of blood was dropped on to a filter paper to capture Plasmodium DNA. Nested PCR was used for parasite molecular detection, while Plasmodium species were identified using the sequenced DNA. Results: A total of 208 and 62 animal blood samples were collected from Gaura village, West Sumba and Fakfak village, West Papua, Indonesia respectively. In total, 32 samples from Gaura contained P. falciparum or P. vivax, while the Plasmodium percentage in buffalo, horse, goat, and dogs were 20.7%, 14.3%, 5.8%, 16.7%, respectively. P. knowlesi was not found in any of the samples, and no other species were detected in 18 pig blood samples. Conclusion: Human Plasmodium existence among domestic animals in Indonesia partly explains the high prevalence and persistence of malaria in some endemic areas due to a reservoir host presence. Therefore, future studies need to ascertain the cause.

Integration of solid-phase microextraction and surface-enhanced Raman spectroscopy for in-vivo screening of polybrominated diphenyl ether

The monitoring of polybrominated diphenyl ethers (PBDEs) is of great significance owing to their high persistence, bioaccumulation, and toxicity to humans and animals. In this study, a sensitive and reproducible probe that integrates solid-phase microextraction and surface-enhanced Raman spectroscopy (SPME-SERS) was developed for screening PBDEs in multiphase specimens, including live fish, water, and electrical products. A roughed Cu fiber with an Ag layer was fabricated with dual functions. BDE-15 was readily extracted and detected on the SPME-SERS probe consisting of propanethiol-modified Ag nanoplates on a Cu wire. A clear linear relationship (R2 = 0.988) was established between the SERS intensity at 782 cm−1 and the logarithmic concentrations (from 100 ppb to 100 ppm), with a detection limit of 15 ppb. This proposed method enables continuous in vivo monitoring in fish without complicated pretreatments. The results obtained by this SPME-SERS approach were validated by high-performance liquid chromatography and showed good agreement. This “extracting and detecting” SPME-SERS method provides a potential tool to monitor the occurrence, formation, and migration of PBDEs.

A Systematic Review of Nano- and Microplastic (NMP) Influence on the Bioaccumulation of Environmental Contaminants: Part I—Soil Organisms

Nano- and microplastics (NMPs) are a group of contaminants that cause concern due to their abundance in the environment, high persistence, and interaction with other contaminants. This review aims to understand the role of NMP in the bioaccumulation of environmental contaminants. For that, a comprehensive literature search was conducted to identify publications that compared the uptake of contaminants in the presence and absence of NMP. In this part I, twenty-eight publications of the terrestrial compartment were analyzed. Two main taxonomic groups were studied, namely, earthworms and terrestrial plants. In earthworms, most studies observed an increase in the bioaccumulation of the contaminants, while in plants, most studies observed a decrease in the bioaccumulation. Changes in bioavailable fractions of contaminants due to NMP presence was the main reason pointed out by the authors for their outcomes. Moreover, biological aspects were also found to be important in defining how NMPs affect bioaccumulation. Dermal damage and changes in contaminant-degrading bacteria in the gut of earthworms caused an increase in bioaccumulation, and root pore blockage was a common reason for the decrease in the bioaccumulation of contaminants in plants. Nevertheless, such effects were mainly observed at high, unrealistic NMP concentrations. Finally, knowledge gaps were identified, and the limitations of this systematic review were presented.

Selective Label-Free Electrochemical Aptasensor Based on Carbon Nanotubes for Carbendazim Detection

One of the most widely used pesticides in Chile is carbendazim (CBZ), which in agriculture is used to protect crops from fungal diseases that commonly occur in rice, vegetable, and fruit crops. However, prolonged exposure to it, and its high persistence, can cause adverse health effects. Therefore, it is necessary to determine the presence of CBZ through rapid detection methods in food samples to prevent ingestion and exposure to this pesticide at risk concentrations. In this work, a label-free electrochemical aptasensor based on functionalized carbon nanotubes was prepared for CBZ detection. The carbodiimide reaction between the amino-terminated aptamer and the carboxylic groups of carbon nanotubes achieved the covalent immobilization of the aptamer. The immobilized aptamer changed its conformation when it detected CBZ and blocked access to the redox mediator on the electrode surface, resulting in a measurable decrease in the voltammetric response. Under the optimal conditions, the aptasensor featured a linear detection range between 1.0 and 50.0 nM, with a detection limit of 4.35 nM. Moreover, the aptasensor exhibited good selectivity for CBZ, among other pesticides, and good repeatability. For CBZ detection in tomatoes, the aptasensor accurately measured CBZ content in a sample prepared using the standard addition method. This work provides a simple, rapid, sensitive, and selective biosensor for CBZ detection and quantification in food samples.

Development and Evaluation of Bacteriophage Cocktail to Eradicate Biofilms Formed by an Extensively Drug-Resistant (XDR) Pseudomonas aeruginosa.

Extensive and multiple drug resistance in P. aeruginosa combined with the formation of biofilms is responsible for its high persistence in nosocomial infections. A sequential method to devise a suitable phage cocktail with a broad host range and high lytic efficiency against a biofilm forming XDR P. aeruginosa strain is presented here. Out of a total thirteen phages isolated against P. aeruginosa, five were selected on the basis of their high lytic spectra assessed using spot assay and productivity by efficiency of plating assay. Phages, after selection, were tested individually and in combinations of two-, three-, four-, and five-phage cocktails using liquid infection model. Out of total 22 combinations tested, the cocktail comprising four phages viz. φPA170, φPA172, φPA177, and φPA180 significantly inhibited the bacterial growth in liquid infection model (p < 0.0001). The minimal inhibitory dose of each phage in a cocktail was effectively reduced to >10 times than the individual dose in the inhibition of XDR P. aeruginosa host. Field emission-scanning electron microscopy was used to visualize phage cocktail mediated eradication of 4-day-old multi-layers of XDR P. aeruginosa biofilms from urinary catheters and glass cover slips, and was confirmed by absence of any viable cells. Differential bacterial inhibition was observed with different phage combinations where multiple phages were found to enhance the cocktail's lytic range, but the addition of too many phages reduced the overall inhibition. This study elaborates an effective and sequential method for the preparation of a phage cocktail and evaluates its antimicrobial potential against biofilm forming XDR strains of P. aeruginosa.

Adsorptive and photocatalytic performance of cobalt-doped ZnTiO3/Ti3C2Tx MXene nanohybrids towards tetracycline: Kinetics and mechanistic insight.

Tetracycline (TC) antibiotics are widely used in animal husbandry and can cause environmental risk due to its high ecological toxicity and persistence. In this study, cobalt doped/ZnTiO3 (ZTO)/Ti3C2Tx MXene (ZCxTM, x indicates wt% of Co loading) was synthesized and explored to remove TC by adsorption and photocatalysis under visible light irradiation. The as-prepared ZC5TM was characterized using various analytical techniques, and key operating parameters such as solution pH, background ions, and temperature were systematically investigated. Interestingly, ZC5TM (14.9mg/g) showed excellent adsorption capacity for TC, which was higher than activated carbon (7.7mg/g), ZTO (4.9mg/g), ZC3T (5.2mg/g), ZC5T (5.3mg/g), MXene (12.1mg/g), ZTOM (12.5mg/g), and ZC3TM (12.9mg/g). The pseudo-second-order kinetics and Langmuir isotherm models well explained the effect of contact time and initial concentrations on the adsorption of TC. The adsorption process was primarily through the electrostatic attraction, surface complexation, and hydrogen bonding. In addition, MXene and Co doped on ZTO served as co-catalyst and reduced recombination rate of photo-generated e--h+ pairs by the intimate interface of its heterojunction. Thus, ZC5TM was highly effective for the photocatalytic degradation of residual TC after adsorption by showing 18% TC degradation rate, compared to 8% and 9% degradation rate for ZTO and MXene, respectively. There results finally support the feasible use of ZC5TM as efficient adsorbent and photocatalyst in removal of TC in wastewater.

The Impact of Global Financial Crisis and COVID-19 Pandemic on Crude Oil Futures Returns

This study investigates the impact of the global financial crisis and of the present COVID-19 pandemic on daily and weekly Crude oil futures using four variants of ARMA-GARCH models: ARMA-sGARCH, ARMA-eGARCH, ARMA-TGARCH and ARMA- aPARCH with dummy variables We also investigated the persistence, half-life and backtesting of the models. This study therefore seeks to contribute to the body of literature on the impact of the global financial crisis and the present COVID-19 pandemic on the crude oil futures market. The impact of the global financial crisis and the COVID-19 on the crude oil futures has not been investigated at present. We obtained and analyzed the daily and weekly crude oil futures from secondary sources. The daily crude oil futures used in this study cover the period from 4th January 2000 to 27th April 2020 while the weekly crude oil futures covered the period from 2nd January 2000 to 26th April 2020. The global financial crisis period covered the period from 2nd July 2007 to 31st March 2009 and the current COVID-19 pandemic covered the period from 1st January 2020 to 27th April, 2020. The study used both Student t and skewed Student t innovations with AIC, goodness-of-test fit and backtesting to select the best model. Most of the estimated ARMA-GARCH models are supported by skewed Student t distribution while most of the ARMA-GARCH models exhibited high persistence values in the presence of the global financial crisis and the COVID-19 pandemic. In the overall, the estimated ARMA(1,0)-eGARCH(2,1) and ARMA(1,0)-eGARCH(2,2) model for daily crude oil futures and weekly crude oil futures respectively have been significantly impacted by the global financial crisis and the Present COVID-19 pandemic while the preferred estimated models also passed the goodness-of-test fit and backtesting. This study recommends shareholders and investors should think outside the box as crude oil futures tend to be affected by the global financial crisis and COVID-19 pandemic while countries also that depend mostly on crude oil are encouraged to diversify their economy in order to survive and be sustained during the financial and health crisis.

P618 Long-term real-world data of Ustekinumab in Ulcerative Colitis – the Stockholm Ustekinumab study – STOCUSTE

Abstract Background Background: Ustekinumab (UST) is an anti-interleukin-12/23 antibody in the treatment of inflammatory bowel disease (IBD), mainly used in patients failing anti-TNF-agents. The STOCUSTE study includes patients treated at four hospitals in Stockholm to provide long-term real-world data. Methods Methods: This was a retrospective study including patients diagnosed with ulcerative colitis and treated with UST between years 2016 and 2021. The patients were followed from start of UST until withdrawal of treatment for any reason, or until end of study follow-up, July 31, 2021.We assessed disease activity; Physician Global Assessment (PGA); Ulcerative Colitis Endoscopic Index of Severity (UCEIS) score, laboratory parameters and drug persistence. The primary outcome was remission (PGA = 0) and response (decrease PGA ≥ 1 from baseline) at 3 and 12 months, respectively. Results Results: 96 patients, 44 women and 52 men were included. The patients had either extensive colitis (68%), left-sided colitis (29%) or proctitis (3%). All but two patients were anti-TNF-experienced; 94 (98%) had failed ≥1, 59 (61%) ≥2 and 34 (35%) ≥3 anti-TNF-drugs. At inclusion 92 patients (96%) had active disease and 4 patients were in remission, 48 (50%) were on oral or topical corticosteroids, 13 (14%) had thiopurines. At 12 months only 9% were on oral or topical corticosteroids. Among patients who were treated with UST, 9/71 (6%) were in remission at 3 months, and 26/33 (78%) patients were in remission at 12 months. Withdrawal from treatment during the first 12 months was 36 (38 %), mainly due to persisting disease activity (20%); 8% were withdrawn due to adverse events, 2% needed bowel surgery, and 2% were lost to follow up. Conclusion Conclusions: In this group of difficult-to-treat patients with ulcerative colitis, Ust was shown to be effective in the majority, with high drug persistence at 12 months in combination with a favorable safety profile.

P629 Real-life treatment persistence and treatment outcomes of Finnish patients with Inflammatory Bowel Disease receiving vedolizumab as first-line biological treatment

Abstract Background Vedolizumab is a gut selective anti-lymphocyte trafficking monoclonal antibody directed towards the integrin α 4β 7. The efficacy and safety of vedolizumab in the treatment of adults with moderately to severely active Crohn’s disease (CD) or ulcerative colitis (UC) are well-established in randomized clinical trials and real-world evidence studies. However, real-world data are limited on vedolizumab therapy used on biological naïve CD and UC patients. Here, we analyse treatment persistence, treatment outcomes, and reasons for treatment discontinuation of vedolizumab as a first-line biological treatment in CD and UC patients in a Finnish real-world setting. Methods This was an observational, retrospective, multi-centre registry study. The cohort included all adult (≥ 18 years of age) patients with a diagnosis of CD or UC who initiated vedolizumab as a first-line biological treatment between May 2014, and June 2020, in the five Finnish university hospital districts. Clinical data were collected from electronic health records. The Prescription Register by the Finnish Social Insurance Institution was the data source for prescribed IBD treatments. Treatment persistence was defined as the time from initiation to discontinuation of therapy. P-values were calculated by using paired t-test. Results The cohort consisted of 54 CD and 69 UC patients treated with vedolizumab as a first-line biological treatment. The mean ages were 61.9 and 56.8 years for CD and UC at the time of vedolizumab start, respectively. Disease duration was 10.9 years in CD and 10.5 years in UC. Altogether, 35.8% of patients had a history of cancer. At month 12, treatment persistence was 84.9% (n=44) in CD and 64.7% (n=41) in UC cohorts (Figure 1). Most vedolizumab discontinuations (CD, n=11; UC, n=26) were due to lack of efficacy, and treatment discontinuations due to adverse events were rare (n&amp;lt;5). Vedolizumab was associated with favourable treatment outcomes, as indicated by efficacy improvements at 12 months compared with baseline in Harvey-Bradshaw Index (CD, 3.2 vs 4.9, p=0.025), Partial Mayo Score (UC, 3.8 vs 5.1, p=0.021), Physician’s Global Assessment (CD, 0.9 vs 1.8, p&amp;lt;0.001; and UC, 0.4 vs 2.1, p&amp;lt;0.001) scores, and positive endoscopic Mayo Score (UC, 0.7 vs 2.2, p&amp;lt;0.001) and biochemical outcomes. Conclusion Vedolizumab showed high treatment persistence and positive treatment outcomes such as improvements in efficacy, endoscopic activity, and biochemical parameters when used as the first-line biological treatment.

P634 Ustekinumab and vedolizumab as first-line biological therapy for inflammatory bowel disease. A multicenter study based on the ENEIDA registry.

Abstract Background The use of ustekinumab (UST) and vedolizumab (VDZ) as first line therapy for inflammatory bowel disease (IBD) is increasing due to safety reasons and contraindications of anti-TNFs. However, there are no studies evaluating their efficacy and safety in clinical practice under these circumstances. Thus, our aims were to describe bionaïve patients’ characteristics starting VDZ or UST and to evaluate treatment persistence of these drugs and their safety profile in this scenario. Methods Descriptive, retrospective and multicenter study based on the ENEIDA registry (a large, prospectively maintained database of the Spanish Working Group in IBD –GETECCU). All IBD patients never exposed to biological agents who started VDZ or UST as first-line biological treatment were identified. Results Out of 29,450 IBD patients ever exposed to biological drugs included in the ENEIDA registry, 924 patients met the inclusion criteria. Of these, 366 (40%) started UST and 558 (60%) VDZ as first line biological therapy. UST group: 48% women, 90% Crohn’s disease (43% ileal; 13% colic; 43.5% ileocolic; 31% upper gastrointestinal involvement; 25% stricturing behaviour; 12% penetrating, 18% perianal disease), 10% ulcerative colitis (74% extensive, 17% left-sided, 9% proctitis), 27% had extraintestinal manifestations (EIM). Median age at the beginning of UST was 57 years (IQR 57-70), 17% patients had a past history of malignancy and, 34% had associated comorbidities. UST indication was luminal activity except in 2% for perianal disease and 5% for EIM. At the end of follow-up (median 14 months [IQR 6-30]), 12 patients (3.3%) developed adverse effects (AEs) that led to treatment discontinuation in the majority of them (92%). VDZ group: 44% women, 42% Crohn’s disease (44% ileal; 18% colic; 38% ileocolic; 25% upper gastrointestinal involvement; 28% stricturing behaviour; 13% penetrating; 7% perianal disease), 58% ulcerative colitis (50% extensive, 42% left-sided, 8% proctitis), 17% had EIM. The median age at the beginning was 61 years (IQR 48-71), 24% had past history of malignancy and, 34% associated comorbidities. The indication was exclusively luminal activity. At the end of follow-up (median 21 months [IQR 8-36]), 36 patients (6.5%) had AEs, that lead to treatment withdrawal in 67% of them (24 patients). Cumulative treatment persistence rates were 78%, 60% and 50% for VDZ and 85%, 75% and 66% for UST at 12, 24 and 36 months, respectively (P&amp;lt;0.001). Conclusion In clinical practice, VDZ and UST are used first-line particularly in elderly patients with comorbidities. Both treatments have a good safety profile and a high persistence of treatment, being superior for ustekinumab.

Toxicity Effects of Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonate (PFOS) on Two Green Microalgae Species.

Amongst per- and polyfluoroalkyl substances (PFAS) compounds, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) have a high persistence in physicochemical and biological degradation; therefore, the accumulation of PFOS and PFOA can negatively affect aquatic organisms and human health. In this study, two microalgae species (Chlorella vulgaris and Scenedesmus obliquus) were exposed to different concentrations of a PFOS and PFOA mixture (0 to 10 mg L-1). With increases in the contact time (days) and the PFAS concentration (mg L-1) from 1 to 7, and 0.5 to 10, respectively, the cell viability, total chlorophyll content, and protein content decreased, and the decrease in these parameters was significantly greater in Scenedesmus obliquus. As another step in the study, the response surface methodology (RSM) was used to optimize the toxicity effects of PFAS on microalgae in a logical way, as demonstrated by the high R2 (>0.9). In another stage, a molecular docking study was performed to monitor the interaction of PFOS and PFOA with the microalgae, considering hydrolysis and the enzymes involved in oxidation-reduction reactions using individual enzymes. The analysis was conducted on carboxypeptidase in Chlorella vulgaris and on c-terminal processing protease and oxidized cytochrome c6 in Scenedesmus obliquus. For the enzyme activity, the affinity and dimensions of ligands-binding sites and ligand-binding energy were estimated in each case.

Insights into sorption and molecular transport of atrazine, testosterone, and progesterone onto polyamide microplastics in different aquatic matrices

Microplastics can act as vectors of a wide class of contaminants in aquatic environments. The sorption behavior of two hormones known to cause adverse effects in biota even in low concentrations (testosterone-TTR and progesterone-PGT), and a pesticide with a high environmental persistence known as endocrine disruptor chemical (atrazine-ATZ) onto polyamide (PA) microplastics is investigated under different aquatic matrices using kinetic and isotherm experiments. The sorption equilibrium is achieved in 48 h, and the experimental results are better fitted by pseudo-2nd-order model. Langmuir isotherm better describes the sorption of the contaminants onto PA microplastics. PGT presents the highest sorption efficiency at around 90%, followed by TTR at 70% and ATZ at approximately 20%. Moreover, ATZ is the contaminant with the highest desorption efficiency (∼65%), indicating its preference for staying solubilized in water. Combining classical molecular dynamics and density functional theory calculations, the sorption energies were calculated as 12–15 kcal mol−1, 13–16 kcal mol−1, and 19–22 kcal mol−1 for PGT, TTR, and ATZ, respectively, showing that PGT needs less energy to be transferred from the solvent network to the PA surface, in agreement with experimental results. The sorption mechanism is driven by hydrogen bonds onto PA outer surface, while the electrostatic interactions dominate the PA inner surface sorption. Moreover, the sorption efficiency is statistically different between the investigated matrices, indicating that physicochemical characteristics of water systems could influence the interactions between PA-contaminant. In seawater, the phenomena of salting-out/in and competitive sorption with saline ions are observed for three contaminants. The PA-contaminant complexes are more polar and soluble than the dissociated ones, which increases the contaminant's co-transport by PA in water.

Development and inter-laboratory validation of analytical methods for glufosinate and its two metabolites in foods of plant origin.

Glufosinate is widely used to control various weeds. Glufosinate and its main metabolites have become the focus of attention because of their high water solubility and persistence in aquatic systems. Quantification of the agrochemical product and its metabolite residues is essential for the safety of agricultural products. In this study, a highly specific, simple method was developed to directly determine glufosinate and its metabolite residues in 21 plant origin foods by liquid chromatography with tandem mass spectrometry (LC-MS/MS), and it was validated on 11 foods in five laboratories. Finally, the repeatability limit, reproducibility limit, and uncertainty of the method were calculated based on these validated data and used to support the more accurate detection results. Four different chromatographic columns were used to analyze three target compounds, and the anionic polar pesticide column showed the optimum separation and peak shape. Composition of the mobile phase, extraction solvent, and the clean-up procedure were optimized. The developed method was validated on 21 plant origin foods. The average recoveries were 74-115% for all matrices. The validation results of five laboratories showed this method had a good repeatability (RSDr < 9.5%) and reproducibility (RSDR < 18.9%). The method validation parameters met the requirements of guidance established by the European Union (EU) and China for pesticide residue analysis. This methodology can be used for a routine monitoring that performs well forglufosinate and its metabolite residues.

COVID-induced economic uncertainty, tasks and occupational demand.

Using monthly online job postings data at the occupation-US-state level in January–December 2020, we provide novel evidence on how COVID-induced economic uncertainty has impacted the occupational composition of US labour demand. The effects are identified by exploiting monthly variation in country-level uncertainty along with pre-COVID differences in shares of occupation-state pairs in occupational country-wide employment and occupational task content. Some of the effects are consistent with the secular and episodic aspects of routine-biased technological change (RBTC) leading to job polarisation and growing complementarity between cognitive analytical and interactive tasks. Interestingly, however, other effects are seemingly at odds with RBTC-induced job polarisation and rather rationalised by idiosyncratic features of the shock (e.g. health emergency) and responses to it (e.g. social distancing, lockdowns). Although additional evidence points to high persistence of most of these effects in 2020, further research in this direction would shed light on whether the effects will persist through the post-COVID era or phase out.

Critical review on biogeochemical dynamics of mercury (Hg) and its abatement strategies

Mercury (Hg) is among the naturally occurring heavy metal with elemental, organic, and inorganic distributions in the environment. Being considered a global pollutant, high pools of Hg-emissions ranging from >6000 to 8000 Mg Hg/year get accumulated by the natural and anthropogenic activities in the atmosphere. These toxicants have high persistence, toxicity, and widespread contamination in the soil, water, and air resources. Hg accumulation inside the plant parts amplifies the traces of toxic elements in the linking food chains, leads to Hg exposure to humans, and acts as a potential genotoxic, neurotoxic and carcinogenic entity. However, excessive Hg levels are equally toxic to the plant system and severely disrupt the physiological and metabolic processes in plants. Thus, a plausible link between Hg-concentration and its biogeochemical behavior is highly imperative to analyze the plant-soil interactions. Therefore, it is requisite to bring these toxic contaminants in between the acceptable limits to safeguard the environment. Plants efficiently incorporate or absorb the bioavailable Hg from the soil thus a constructive understanding of Hg uptake, translocation/sequestration involving specific heavy metal transporters, and detoxification mechanisms are drawn. Whereas recent investigations in biological remediation of Hg provide insights into the potential associations between the plants and microbes. Furthermore, intense research on Hg-induced antioxidants, protein networks, metabolic mechanisms, and signaling pathways is required to understand these bioremediations techniques. This review sheds light on the mercury (Hg) sources, pollution, biogeochemical cycles, its uptake, translocation, and detoxification methods with respect to its molecular approaches in plants.