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Skeletal muscle has recently arisen as a regulator of central nervous system (CNS) function and aging, secreting bioactive molecules known as myokines with metabolism-modifying functions in targeted tissues, including the CNS. Here, we report the generation of a transgenic mouse with enhanced skeletal muscle lysosomal and mitochondrial function via targeted overexpression of transcription factor E-B (TFEB). We discovered that the resulting geroprotective effects in skeletal muscle reduce neuroinflammation and the accumulation of tau-associated pathological hallmarks in a mouse model of tauopathy. Muscle-specific TFEB overexpression significantly ameliorates proteotoxicity, reduces neuroinflammation, and promotes transcriptional remodeling of the aged CNS, preserving cognition and memory in aged mice. Our results implicate the maintenance of skeletal muscle function throughout aging in direct regulation of CNS health and disease and suggest that skeletal muscle originating factors may act as therapeutic targets against age-associated neurodegenerative disorders.

Recent studies have described active nitrogen fixation in high-latitude waters, but the ecological controls on the occurrence or activity of nitrogen-fixing organisms (diazotrophs) in such systems remain unknown. Turnover rates and top-down controls are also general knowledge gaps for marine diazotrophs. We detected abundant UCYN-A (endosymbiotic nitrogen-fixing cyanobacteria) in the Gulf of Anadyr, western Bering Sea, which correlated with high dissolved iron to dissolved inorganic nitrogen ratios (Fe : DIN) due to riverine input. Growth and grazing mortality of UCYN-A sublineages were almost balanced with higher biomass-turnover rates compared to the whole phytoplankton community, indicating selective grazing of UCYN-A in nitrogen-depleted waters. Grazing rates on UCYN-A1 (small cells) were higher than for UCYN-A2/3/4 (large cells), consistent with the general size dependence of phytoplankton growth and grazing mortality. We found that Fe : DIN is a major determinant of UCYN-A abundances in high-latitude waters, where UCYN-A could make substantial contributions to plankton food-web cycling.

Studies on feedback given to second language (L2) learners have focused primarily on learners' response to feedback on language. This study explores how L2 learners in one university EAP class respond to teacher written feedback on all aspects of writing and the factors that may affect their response. Using data from student initial and revised texts, the study first looks at nine learners' uptake of feedback. Then, adopting a case study approach and using data from retrospective interviews, the study examines how three learners engage with feedback on different dimensions of their writing. Findings show that learners took up almost all feedback suggestions regardless of form or focus. Yet, learners' engagement with the feedback differed. Using activity theory (AT), we explain the learners' engagement with the feedback received by reference to the interaction of context and individual-related factors. Our findings highlight the complexity of learner behavior in response to feedback.

Understanding how phytoplankton growth responds to temperature is critical for forecasting marine productivity in a warming ocean. While previous laboratory studies have shown that phytoplankton thermal traits such as optimal temperature (Topt) can be affected by nutrient availability, it is unclear whether this can be extrapolated to natural communities. To address this, we tested the impacts of nutrient availability on the thermal responses of two cosmopolitan diatom genera, Pseudo‐nitzschia and Leptocylindrus, through a series of in situ manipulation experiments on natural phytoplankton communities. Analysis of the thermal performance curves revealed that nutrient limitation during summer not only limited the growth of these two genera but also reduced their Topt and the maximum growth rates (μmax). Topt was close to or lower than in situ temperature under ambient nutrient conditions, suggesting that further warming may have a detrimental effect on their growth. However, increasing nutrient supply could counteract this by enhancing Topt and μmax. To further confirm the interactive effects of nutrients and temperature on diatoms, we analyzed a 20‐yr monitoring dataset on Pseudo‐nitzschia, Leptocylindrus, and the whole diatom assembly in Hong Kong coastal waters. We found that the abundances of marine diatoms were significantly higher at high temperatures under nutrient‐rich environments while relatively low under low nutrient concentrations. Findings on natural diatom cell density align with the growth performance derived from in situ manipulation experiments, suggesting that abundant nutrients bolster marine diatoms in coping with warming. Our results highlight the importance of considering the influence of nutrient availability on thermal response of phytoplankton growth, which sheds light on how marine primary production may change under climate warming. [ABSTRACT FROM AUTHOR]

Implementing translanguaging in language education requires a rich understanding of learners' complex meaning-making practices. Enactments of translanguaging simply as an acknowledgement of learners' home languages and translation practices reflects a confusion between the concept of translanguaging and translation and a lack of understanding of the complexities involved within these two practices for language learning. This study explores how a university lecturer and a graduate student enact translation and translanguaging in a collaborative dialogue to solve a linguistic problem. Based on a thematic analysis of their text-message interaction and evidence from stimulated recalls, we demonstrate how practices of translation and translanguaging are different and yet intertwined as affordances for learning. We also consider the diverse linguistic, emotional, social, and historical resources that both interlocutors leverage to facilitate a collaborative learning space. We conclude by highlighting the importance of a multilingual pedagogical design that goes beyond visibility and audibility of multiple languages. [ABSTRACT FROM AUTHOR]

Blooms of microalgal red tides and macroalgae (e.g., green and golden tides caused by Ulva and Sargassum) have caused widespread problems around China in recent years, but there is uncertainty around what triggers these blooms and how they interact. Here, we use 30 years of monitoring data to help answer these questions, focusing on the four main species of microalgae Prorocentrum donghaiense, Karenia mikimotoi, Noctiluca scintillans, and Skeletonema costatum) associated with red tides in the region. The frequency of red tides increased from 1991 to 2003 and then decreased until 2020, with S. costatum red tides exhibiting the highest rate of decrease. Green tides started to occur around China in 1999 and the frequency of green tides has since been on the increase. Golden tides were first reported to occur around China in 2012. The frequency of macroalgal blooms has a negative linear relationship with the frequency and coverage of red tides around China, and a positive correlation with total nitrogen and phosphorus loads as well as with atmospheric CO2 and sea surface temperature (SST). Increased outbreaks of macroalgal blooms are very likely due to worsening levels of eutrophication, combined with rising CO2 and SST, which contribute to the reduced frequency of red tides. The increasing grazing rate of microzooplankton also results in the decline in areas affected by red tides. This study shows a clear shift of algal blooms from microalgae to macroalgae around China over the past 30 years driven by the combination of eutrophication, climate change, and grazing stress, indicating a fundamental change in coastal systems in the region. [ABSTRACT FROM AUTHOR]

Studies on feedback given to second language (L2) learners have focused primarily on learners' response to feedback on language. This study explores how L2 learners in one university EAP class respond to teacher written feedback on all aspects of writing and the factors that may affect their response. Using data from student initial and revised texts, the study first looks at nine learners' uptake of feedback. Then, adopting a case study approach and using data from retrospective interviews, the study examines how three learners engage with feedback on different dimensions of their writing. Findings show that learners took up almost all feedback suggestions regardless of form or focus. Yet, learners' engagement with the feedback differed. Using activity theory (AT), we explain the learners' engagement with the feedback received by reference to the interaction of context and individual-related factors. Our findings highlight the complexity of learner behavior in response to feedback. [ABSTRACT FROM AUTHOR]