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Microplastics from mulch films can be a source of chemical contamination to agricultural soils. In this context, biodegradable films have been widely positioned as a greener choice. However, their sorption/desorption capabilities, in contrast to the conventional plastic types remain understudied. It is for this reason that objective evaluation of their interactions with residual agricultural contaminants becomes important. Our findings reveal that polyethylene (PE) mulch films retained lower amounts of pesticide residues and demonstrated a higher desorption/release [median desorption = 71.86 μg/L or about 50%], while polybutylene adipate terephthalate (PBAT) mulch films retained higher amounts of pesticide residues onto their surface and demonstrated a much lower desorption [median desorption = 24.27 μg/L or about 17%] after a spraying event. A higher ambient temperature had no significant effect on final desorption amounts in both PE [median = 65.27 μg/L at 20 °C and 74.23 μg/L at 40 °C] and PBAT [median = 24.26 μg/L at 20 °C and 24.78 μg/L at 40 °C] mulch films. However, it did favour a faster desorption pace in PE films. Desorption in PBAT and PE plastic types was correlated with the log K ow value [Spearman's correlation: 0.857 and 0.837 respectively, p < 0.05]. However, only a moderate correlation with pKa was observed in PBAT [Spearman's correlation: 0.478, p < 0.05], while none for PE plastic type. Sorption of pesticides onto biodegradable PBAT microplastics were best explained by Elovich [R2: 0.937–0.959] and pseudo-second order kinetics [R2: 0.942–0.987], suggesting the presence of chemisorption. Furthermore, Weber Morris plots suggested the presence of a multi-step process and Boyd plots indicated that film diffusion or chemical bond formation was the rate-limiting step governing this phenomenon. [Display omitted] • Biodegradable mulch films retained higher amounts of pesticides than PE films. • Higher temperature increased pace of desorption in conventional mulch films. • Sorption in biodegradable MP explained by Elovich and pseudo-second order models. • Chemical bonding governed the sorption process and was the rate-limiting step. • Log K ow cutoff value was lower for biodegradable than conventional plastic. [ABSTRACT FROM AUTHOR]

Abstract: Electron diffraction and high resolution electron microscopy have been used to characterize two new one-dimensional superstructures in the Aph name="sbnd" />O system (A=Ca, Sr) related to the 2H-ABO3-type. They are formed by the intergrowth of n A3A′BO6 blocks, showing the Sr4RhO6-type, with A12A′2B8O30 blocks, constituted by two A3O9 and two A3A′O6 layers alternating in the stacking sequence 1:1, leading to the A27A′7B13O60 () and A30A′8B14O66 () compositions. A crystallographic shear mechanism is proposed to describe the structural relationship between Sr4RhO6 (A3A′BO6-type) and the new superstructures. [Copyright &y& Elsevier]

Abstract: The purpose of this study was to compare the effects of microwave thawing and water bath thawing on white sauces prepared with two different native starches (potato and corn) and a modified waxy maize starch. The linear viscoelasticity, microstructure and thermographic characteristics of the thawed sauces were analysed and compared with those of freshly prepared sauces. Due to starch retrogradation, the quality characteristics of the native starch-based sauces were strongly affected by freezing and thawing, but these effects were smaller for microwave heating than for heating in a water bath. The water accumulated during freezing tended to diffuse more uniformly in the microwave-thawed sauces, providing a more homogeneous structure than that of the water bath-thawed sauces. It is hypothesized that the shorter heating time in microwave reduces the extent of starch retrogradation during thawing and that local high temperature zones in the microwave may be more effective in the melting of retrograded starch. The dissociated amylose and amylopectin molecules would adsorb the water that is released and help to achieve a more homogeneous distribution of water. The modified starch white sauces were not affected by freezing or by the thawing method. [Copyright &y& Elsevier]

• Proven efficacy of automated clean-up on bee pollen's pesticides extracts. • Pesticides contamination in 85 % of bee pollen samples. • Pesticides concentration higher than the corresponding MRL in 40 % of samples. • No relevant differences in the contamination of organic and conventional bee pollen. • No potential health risk due to bee pollen's pesticides content could be predicted. Pesticide contamination in emerging foods and supplements is currently a topic of great interest. This study focused on the evaluation of pesticide residues in commercial bee pollen samples to evaluate the risk associated with their consumption. To this end, an automated clean-up method for the pesticide extracts of bee pollen was developed. An LC-MS/MS and a GC-MS/MS method were validated for the analysis of 353 pesticides in 80 bee pollen samples purchased from different countries. The results showed the presence of 77 different pesticide residues in bee pollen, including plant protection chemicals and veterinary treatments. 85 % of the samples were contaminated with pesticides and no relevant differences were found between conventional and organic samples. Pesticide concentrations exceeding the imposed MRL were found in 40 % of the samples, but the risk assessment showed that consumers are not exposed to an unacceptable risk when consuming the evaluated bee pollen. [ABSTRACT FROM AUTHOR]

Bee pollen is a natural product valued for its nutritional and medicinal benefits, and it is gaining popularity for its potential use as a feed and supplement for cattle. However, due to the lack of information on the extent of its contamination with dangerous substances, there are still a number of questions regarding the safety of this beekeeping product. Mycotoxins, in particular, are a family of molecules typically found in food that may pose a health risk to consumers and for which no legal restrictions are set in bee pollen. In this study, the presence of five mycotoxins - aflatoxin B1, ochratoxin A, zearalenone, deoxynivalenol, and toxin T2 - was evaluated in 80 bee pollen samples from diverse climatic areas, organic and conventional beekeeping, with different floral composition, and commercial format - fresh, dry, or bee bread. The analyses were performed by enzyme-linked immunosorbent assays and the obtained results showed the presence of the least one of the analyzed mycotoxins in 100% of the samples, with aflatoxin B1 having the highest incidence rate. Monofloral pollens showed lower total mycotoxins concentration compared with the multifloral samples analyzed, while bee bread was the commercial format with the highest total mycotoxins concentration among the analyzed ones. The obtained results were also used to assess the risk associated with single and multiple mycotoxin exposure due to bee pollen consumption by calculating the respective hazard quotients and margins of exposure. In 28% of the analyzed cases, deoxynivalenol exceeded the safe limits, while aflatoxin B1, because of its generally high concentration, resulted of high public health concern in 84% of the considered cases. • 100% of bee pollen samples had quantifiable levels of mycotoxins. • Storage temperature influences the presence of mycotoxins in bee pollen. • Deoxynivalenol exceeds the safe limits of exposure in 28% of the analyzed cases. • Aflatoxin B1 concentration in bee pollen is of high public health concern. [ABSTRACT FROM AUTHOR]

The sorption and vector effect of microplastics on the transfer of pesticides and polycyclic aromatic hydrocarbons (PAHs), as well as its impact on agriculture remain largely unexplored. This comparative study is first to investigate the sorption behavior of different pesticides and PAHs at environmentally realistic concentrations by model microplastics and microplastics derived from polyethylene mulch films. Sorption was found to be up to 90% higher in the case of microplastics derived from mulch films as opposed to pure polyethylene microspheres. For microplastics from mulch films, the sorption percentages for pesticides in media containing CaCl 2 were reported to be: pyridate (75.68% and 52.44%), fenazaquin (48.54% and 32.02%), pyridaben (45.04% and 56.70%), bifenthrin (74.27% and 25.88%), etofenprox (82.16% and 54.16%) and pyridalyl (97.00% and 29.74%) at 5 μg/L and 200 μg/L pesticide concentration levels respectively. For PAHs, the sorption amounts were: naphthalene (22.03% and 48.00%), fluorene (38.99% and 39.00%), anthracene (64.62% and 68.02%) and pyrene (75.65% and 86.38%) at 5 μg/L and 200 μg/L PAH concentration levels respectively. Sorption was influenced by the octanol-water partition coefficient (log K ow) and ionic strength. Kinetics of the process in the case of sorption of pesticides were best explained by pseudo-first order kinetic model (R2 between 0.90 and 0.98) while the best fitting isotherm model was Dubinin-Radushkevich (R2 between 0.92 and 0.99). Results suggest the presence of surface level physi-sorption through a micropore volume filling mechanism and the role of hydrophobic and electrostatic forces. Pesticide desorption data in polyethylene mulch films indicate that pesticides with high log K ow were almost completely retained in mulch films, while those with lower log K ow were desorbed rapidly into the surrounding media. Our study highlights the role of microplastics from plastic mulch films as vectors for pesticide and PAH transport at environmentally realistic concentrations and the factors that influence it. [Display omitted] • MPs from mulch films showed up to 90% higher sorption than pure polyethylene MP. • Compounds with log K ow value below cutoff (around 3) were not sorbed/retained. • Pseudo-first order was the best fitting kinetic model suggesting physisorption. • Dubinin-Radushkevich, the best fitting isotherm suggested micropore volume filling. • Compounds with lower log K ow values were rapidly desorbed from mulch films. [ABSTRACT FROM AUTHOR]

Abstract: The tick protective antigen, subolesin, is a regulatory protein involved in the control of multiple cellular pathways. Subolesin is evolutionary conserved in invertebrates and vertebrates with sequence homology to akirins, a recently renamed group of proteins that were proposed to function as transcription factors in Drosophila and mice. The objective of this research was to provide evidence of the sequence and functional homology between tick subolesin and akirins. The phylogenetic analysis of subolesin and akirins showed that they are evolutionary conserved. The effect of subolesin and akirin2 knockdown was compared in adult ticks and mice, respectively. The results demonstrated that tick subolesin is an ortholog of insect and vertebrate akirins and suggested that these proteins function in the regulation of NF-κB-dependent and independent expression of signal transduction and innate immune response genes. These results suggest that these proteins have an important role in host–pathogen interactions. [Copyright &y& Elsevier]

Purpose: To measure the lifetime prevalence of physical, emotional, and sexual Intimate Partner Violence (IPV) in women attending general practice in Spain and to assess sociodemographic factors associated with the different types of abuse.Methods: The sample included 1402 randomly selected women, aged 18 to 65 years, attending general practice in three Spanish regions. A self-administered structured questionnaire specifically developed for the study was used. Given the overlap between the different types of lifetime abuse, various categories were created by combining the different types. Multiple logistic regression models were developed to identify the sociodemographic factors independently associated with the different categories of abuse.Results: Lifetime prevalence of IPV was 32%, and 14.4% referred having experienced emotional abuse alone. Factors independently associated with all categories of abuse included being separated/divorced/widowed, having three or more children, and lacking social support. Increasing age was protective for physical and emotional abuse (odds ratio = 0.96; 95% confidence interval = 0.93-0.99). Women with the lowest monthly family income (< 600 euro) (1 euro = 1.32 euro) were most likely to experience all IPV categories, except for emotional abuse alone.Conclusions: IPV is a common problem in general practice. The identification of factors associated with this public health problem is essential for its prevention and treatment. [ABSTRACT FROM AUTHOR]