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There has been much debate on whether color categories affect how we perceive color. Recent theories have put emphasis on the role of top-down influence on color perception that the original continuous color space in the visual cortex may be transformed into categorical encoding due to top-down modulation. To test the influence of color categories on color perception, we adopted an RSVP paradigm, where color stimuli were presented at a fast speed of 100 ms per stimulus and were forward and backward masked by the preceding and following stimuli. Moreover, no explicit color naming or categorization was required. In theory, backward masking with such a short interval in a passive viewing task should constrain top-down influence from higher-level brain areas. To measure any potentially subtle differences in brain response elicited by different color categories, we embedded a sensitive frequency-tagging-based EEG paradigm within the RSVP stimuli stream where the oddball color stimuli were encoded with a different frequency from the base color stimuli. We showed that EEG responses to cross-category oddball colors at the frequency where the oddball stimuli were presented was significantly larger than the responses to within-category oddball colors. Our study suggested that the visual cortex can automatically and implicitly encode color categories when color stimuli are presented rapidly. [ABSTRACT FROM AUTHOR]

• Roots of P. australis enhance Fe-OC coupling, especially in low-tide areas. • Rhizosphere Fe-OC fluctuates seasonally, higher in low-tide flats in the growing season. • Plant growth stages significantly influence Fe-OC dynamics in tidal flat wetlands. • Significant rise in FeRB abundance in low-tide flat during non-growing season. • Seasonal shifts in microbial communities affect Fe-OC content in tidal sediments. As sea levels rise, coastal tidal wetlands are increasingly threatened by flooding and salt stress, highlighting the importance of iron (Fe) (hydr-) oxides in soil for stabilizing organic carbon (OC). This study focuses on Phragmites australis , common in the Yangtze River Estuary, exploring the interplay between OC and Fe (hydr-) oxides in the rhizosphere of P. australis across various seasons and elevations. It also examines microbial community shifts in the Fe oxidation–reduction cycle. Results show that in the non-growing season (January), Fe (hydr-) oxides and total organic carbon (TOC) levels in the rhizosphere soil of high-tide P. australis are significantly higher than during the growing season (August), with a notable increase in Fe oxide-bound OC (Fe-OC). The content of Fe-OC in tidal wetland soil fluctuates with plant growth stages and elevation. Notably, during the growing season, the Fe-OC content in the rhizosphere of low-tide P. australis is markedly higher than in high-tide areas, reversing in the non-growing season. The presence of P. australis roots is found to significantly enhance the accumulation and coupling of Fe (hydr-) oxides and OC, especially in low-tide areas compared to bare flats. This coupling is affected by the organic matter contributed by roots, microbial metabolism, and redox conditions of the soil. The study also highlights how plant and microbial metabolism regulate the response of rhizosphere Fe-OC across different tidal flat elevations. In low-tide environments during the non-growing season, the prevalence of Fe-reducing bacteria results in decreased Fe-OC content, while in high-tide areas, increased organic matter input boosts complexed Fe-OC formation. Overall, this study emphasizes the significance of plant metabolism in understanding the impact of sea level rise on Fe-OC stores in tidal wetlands, a vital factor for comprehending C cycling mechanisms and assessing C sequestration potential under future climate change scenarios. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel extractant resin DtBuCH18C6@CG-71 was successfully prepared with simple and low-cost method. • DtBuCH18C6@CG-71 exhibited remarkable separation ability of Sr(II) even in high concentration HNO 3 (3–12 mol/L). • DtBuCH18C6@CG-71 possessed great acid, irradiation and thermal resistance stability. • DtBuCH18C6@CG-71 can adeptly sequesters and recovers Sr(II) from wastewater via an automated separation system. Effective removal of radioactive 90Sr is crucial for both management of spent nuclear fuel and recovery of radioactive strontium resources, while it's still a great challenge due to the presence of high acid levels and intense radiation. Herein, a novel porous resin (DtBuCH18C6@CG-71) were synthesized by introducing 4′,4″(5″)-di- tert -butyldicyclohexano-18-crown-6 onto CG-71 resin using vacuum impregnation. The DtBuCH18C6@CG-71 resin maintains superior adsorption abilities in extreme conditions, including high acid resistance (3–12 mol/L HNO 3), substantial γ-irradiation (200 kGy 60Co), and elevated temperatures (50–100 ℃). Impressively, even when exposed to a high concentration of matrix ions (59 elemental ions), the Sr(II) adsorption ratio onto DtBuCH18C6@CG-71 resin remains near 100 % even in highly acidic condition, which performance outpaces most of commercial resins. Dynamic column tests using an automated separation system further confirmed the superior ability of DtBuCH18C6@CG-71 in term of extracting Sr(II) from wastewater. Given its impressive features, cost-effectiveness, and scalability, DtBuCH18C6@CG-71 resin holds promising potential for 90Sr disposal in nuclear wastewater. [ABSTRACT FROM AUTHOR]