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The development of agricultural technologies has intensified the use of plastic in this sector. Products of plastic degradation, such as microplastics (MPs), potentially threaten living organisms, biodiversity and agricultural ecosystem functioning. Thus, biodegradable plastic materials have been introduced to agriculture. However, the effects of biodegradable plastic substitutes on soil ecosystems are even less known than those of traditional ones. Here, we studied the effects of environmentally relevant concentrations of MPs prepared from a biodegradable plastic (a starch-polybutylene adipate terephthalate blend, PBAT-BD-MPs) on the growth and defense mechanisms of lettuce (Lactuca sativa) in CLIMECS system (CLImatic Manipulation of ECosystem Samples). PBAT-BD-MPs in the highest concentrations negatively affected some traits of growth, i.e., dry weight percentage, specific leaf area, and both C and N contents. We observed more profound changes in plant physiology and biochemistry, as PBAT-BD-MPs decreased chlorophyll content and triggered a concerted response of plant defense mechanisms against oxidative stress. In conclusion, exposure to PBAT-BD-MPs induced plant oxidative stress and activated plant defense mechanisms, leading to oxidative homeostasis that sustained plant growth and functioning. Our study highlights the need for in-depth understanding of the effect of bioplastics on plants. [Display omitted] • The effect of biodegradable microplastics (BD-MPs) on plant health is not well-known. • We used CLIMECS setup to study effect of BD-MPs on growth of lettuce. • BD-MPs affect biochemical traits and to a lesser extent growth of lettuce. • We highlight potentially negative effect of BD-MPs on lettuce health. [ABSTRACT FROM AUTHOR]

The objective of this study is to investigate the effectiveness of a local wearable cooling solution in improving thermal comfort, emotional state, and cognitive performance. The study was conducted in an environmental room with air temperature of 31.5 ± 0.26 °C. Thirty participants performed six cognitive tasks while periodically assessing their thermal experience locally where the cooling (Embr wave) was applied and for the whole body, as well as emotional states. The same protocol was applied to another thirty participants as the control group without local cooling. We also measured mean skin temperature and local skin temperature beneath the cooling device during the whole session. The results showed a significant drop in thermal sensation right after the application of the local cooling. Based on the ASHRAE 7-point scale for the overall thermal sensation vote, the local sensation dropped from 0.8 to −0.4 and the whole-body thermal sensation from 1.34 to 0.87. Over the 60 min of local cooling application, the local thermal sensation dropped from 0.98 to 0.04 and the whole-body thermal sensation dropped from 1.37 to 1.12. Furthermore, the local cooling group showed a significant drop in negative emotions and an increase in positive emotions compared to the control group. For cognitive performance, local cooling groups showed to be more inclined for risk taking for more rewards compared to the control group. The performance of other cognitive tests showed no significant difference between the two groups, even though attention, working memory and creativity were enhanced slightly but insignificantly. [Display omitted] • Proposed a low-energy cooling strategy to improve thermal comfort, emotion, and cognition. • Significant drop in local and whole-body thermal sensation right after the cooling. • Positive emotions increased while negative emotions decreased. • Positive effect of local cooling on risky decision making. [ABSTRACT FROM AUTHOR]

Abstract Microplastic (MP) contamination is ubiquitous in the environment and many species worldwide have been shown to contain MP. The ecological impact of MP pollution is still unknown, thus there is an urgent need for more knowledge. One key task is to identify species suitable as sentinels for monitoring in key eco-compartments, such as coastal waters. In Norway, mussels (Mytilus spp.) have been monitored for hazardous contaminants through OSPAR since 1981. Norway has the longest coastline in Europe and adding MP to the Norwegian Mussel Watch is therefore important in a European and global context. The present study reports MP data in mussels (332 specimens) collected from multiple sites (n = 15) spanning the whole Norwegian coastline. MPs were detected at all locations, except at one site on the west coast. Among the most surprising findings, mussels from the Barents Sea coastline in the Finnmark region, contained significantly more MPs than mussels from most of the southern part of the country, despite the latter sites being located much closer to major urban areas. Only mussels from a site located very close to Oslo, the capital, contained levels similar to those observed in the remote site in Finnmark. In total an average of 1.5 (±2.3) particles ind−1 and 0.97 (±2.61) particles w.w. g−1 was found. The most common MPs were <1 mm in size, and fibres accounted for 83% of particles identified, although there was inter-site variability. Thirteen different polymeric groups were identified; cellulosic being the most common and black rubbery particles being the second. This study suggests Mytilus spp. are suitable for semi-quantitative and qualitatively monitoring of MPs in coastal waters. However, some uncertainties remain including mussel size as a confounding factor that may influence ingestion, the role of depuration and other fate related processes, and this call for further research. Graphical abstract Image 1 Highlights • Mussels are suggested as a sentinel species for coastal microplastic pollution. • Norway has Europe's longest coastline providing a large spatial spread of sites. • Microplastics were found in Mytilus spp. from 14 out of 15 sites. • Highest levels in the far north and in a station near the capital city Oslo. • Thirteen different polymer groups were found, some of special environmental concern. Mussels from 14 out of 15 sites along the Norwegian coast contained microplastics of a total of thirteen different polymers groups. [ABSTRACT FROM AUTHOR]

Sewage sludge used as agricultural fertilizer has been identified as an important source of microplastics (MPs) to the environment. However, the fate of MPs added to agricultural soils is largely unknown. This study investigated the fate of MPs in agricultural soils amended with sewage sludge and the role of surface water runoff as a mechanism driving their transfer to aquatic ecosystems. This was assessed using three experimental plots located in a semi-arid area of Central Spain, which were planted with barley. The experimental plots received the following treatments: (1) control or no sludge application; (2) historical sludge application, five years prior to the experiment; and (3) sludge application at the beginning of the experiment. MPs were analyzed in surface water runoff and in different soil layers to investigate transport and infiltration for one year. The sewage sludge used in our experiment contained 5972–7771 MPs/kg dw. Based on this, we estimated that about 16,000 MPs were added to the agricultural plot amended with sludge. As expected, the sludge application significantly increased the MP concentration in soils. The control plot contained low MP concentrations (31–120 MPs kg−1 dw), potentially originating from atmospheric deposition. The plot treated five years prior to the experiment contained 226–412 and 177–235 MPs kg−1 dw at the start and end of the experiment, respectively; while the recently treated plot contained 182–231 and 138–288 MPs kg−1 dw. Our study shows that MP concentrations remain relatively constant in agricultural soils and that the MP infiltration capacity is very low. Surface water runoff had a negligible influence on the export of MPs from agricultural soils, mobilizing only 0.2–0.4% of the MPs added with sludge. We conclude that, in semi-arid regions, agricultural soils can be considered as long-term accumulators of MPs. [Display omitted] • Sewage sludge increases the concentration of microplastics in agricultural soils. • Microplastic concentrations remain relatively constant over time. • Microplastic infiltration to deeper soil horizons is very low. • Only about 0.2–0.4% of microplastics are mobilized by water runoff in one year. • The impacts of microplastic build-up on soil ecosystems should be further investigated. [ABSTRACT FROM AUTHOR]

An abstract of the article "Exploring the Synthesis and Characterization of an Amine Modified Basic Support for the Nitroaldol Reaction," by Rachel M. Hurley, Amanda J. Hammers, and Jetty L. Duffy-Matzner is presented.