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Land use and land cover (LULC) can significantly alter river water, which can in turn have important impacts on downstream coastal ecosystems by delivering nutrients that promote marine eutrophication and hypoxia. Well-documented in temperate systems, less is known about the way land cover relates to water quality in low-lying coastal zones in the tropics. Here we evaluate the catchment LULC and the physical and chemical characteristics of six rivers that contribute flow into a seasonally hypoxic tropical bay in Bocas del Toro, Panama. From July 2019 to March 2020, we routinely surveyed eight physical and chemical characteristics (temperature, specific conductivity, salinity, pH, dissolved oxygen (DO), nitrate and nitrite, ammonium, and phosphate). Our goals were to determine how these physical and chemical characteristics of the rivers reflect the LULC, to compare the water quality of the focal rivers to rivers across Panama, and to discuss the potential impacts of river discharge in the Bay. Overall, we found that the six focal rivers have significantly different river water characteristics that can be linked to catchment LULC and that water quality of rivers 10 s of kilometers apart could differ drastically. Two focal catchments dominated by pristine peat swamp vegetation in San San Pond Sak, showed characteristics typical of blackwater rivers, with low pH, dissolved oxygen, and nutrients. The remaining four catchments were largely mountainous with >50% forest cover. In these rivers, variation in nutrient concentrations were associated with percent urbanization. Comparisons across Panamanian rivers covered in a national survey to our focal rivers shows that saltwater intrusions and low DO of coastal swamp rivers may result in their classification by a standardized water quality index as having slightly contaminated water quality, despite this being their natural state. Examination of deforestation over the last 20 years, show that changes were

Clinical evidence suggests that mindfulness meditation reduces anxiety, depression, and stress, and improves emotion regulation due to modulation of activity in neural substrates linked to the regulation of emotions and social preferences. However, less was known about whether mindfulness meditation might alter pro-social behavior. Here we examined whether mindfulness meditation activates human altruism, a component of social cooperation. Using a simple donation game, which is a real-world version of the Dictator's Game, we randomly assigned 326 subjects to a mindfulness meditation online session or control and measured their willingness to donate a portion of their payment for participation as a charitable donation. Subjects who underwent the meditation treatment donated at a 2.61 times higher rate than the control (p = 0.005), after controlling for socio-demographics. We also found a larger treatment effect of meditation among those who did not go to college (p

Permafrost degradation is altering biogeochemical processes throughout the Arctic. Thaw‐induced changes in organic matter transformations and mineral weathering reactions are impacting fluxes of inorganic carbon (IC) and alkalinity (ALK) in Arctic rivers. However, the net impact of these changing fluxes on the concentration of carbon dioxide in the atmosphere (pCO2) is relatively unconstrained. Resolving this uncertainty is important as thaw‐driven changes in the fluxes of IC and ALK could produce feedbacks in the global carbon cycle. Enhanced production of sulfuric acid through sulfide oxidation is particularly poorly quantified despite its potential to remove ALK from the ocean‐atmosphere system and increase pCO2, producing a positive feedback leading to more warming and permafrost degradation. In this work, we quantified weathering in the Koyukuk River, a major tributary of the Yukon River draining discontinuous permafrost in central Alaska, based on water and sediment samples collected near the village of Huslia in summer 2018. Using measurements of major ion abundances and sulfate (SO42− ${{\text{SO}}_{4}}^{2-}$) sulfur (34S/32S) and oxygen (18O/16O) isotope ratios, we employed the MEANDIR inversion model to quantify the relative importance of a suite of weathering processes and their net impact on pCO2. Calculations found that approximately 80% of SO42− ${{\text{SO}}_{4}}^{2-}$ in mainstem samples derived from sulfide oxidation with the remainder from evaporite dissolution. Moreover, 34S/32S ratios, 13C/12C ratios of dissolved IC, and sulfur X‐ray absorption spectra of mainstem, secondary channel, and floodplain pore fluid and sediment samples revealed modest degrees of microbial sulfate reduction within the floodplain. Weathering fluxes of ALK and IC result in lower values of pCO2 over timescales shorter than carbonate compensation (∼104 yr) and, for mainstem samples, higher values of pCO2 over timescales longer than carbonate compensation but shorter than the residence time of marine SO42− ${{\text{SO}}_{4}}^{2-}$ (∼107 yr). Furthermore, the absolute concentrations of SO42− ${{\text{SO}}_{4}}^{2-}$ and Mg2+ in the Koyukuk River, as well as the ratios of SO42− ${{\text{SO}}_{4}}^{2-}$ and Mg2+ to other dissolved weathering products, have increased over the past 50 years. Through analogy to similar trends in the Yukon River, we interpret these changes as reflecting enhanced sulfide oxidation due to ongoing exposure of previously frozen sediment and changes in the contributions of shallow and deep flow paths to the active channel. Overall, these findings confirm that sulfide oxidation is a substantial outcome of permafrost degradation and that the sulfur cycle responds to permafrost thaw with a timescale‐dependent feedback on warming. Key Points: Sulfide oxidation sources approximately 80% of dissolved SO42− ${{\text{SO}}_{4}}^{2-}$ in the Koyukuk River, Alaska, and may act as a positive feedback on modern warmingInversion calculations reveal weathering is a CO2 sink on timescales of ∼5–10 kyr and a CO2 source on timescales of ∼10 kyr to ∼10 MyrIncreases in the absolute and relative abundance of SO42− ${{\text{SO}}_{4}}^{2-}$ in the Koyukuk River and Yukon River over the past decades suggests thaw‐induced sulfide oxidation [ABSTRACT FROM AUTHOR]

Language attitudes refer to individuals' views, judgments, and emotions regarding a language or linguistic variety. These attitudes are shaped by various factors such as cultural, social, historical, and political contexts. In the case of Philippine English, attitudes regarding this linguistic variant have shifted, reflecting evolving views and ideals within Philippine culture. Thus, the study aimed to provide insights into the social, cultural, and linguistic factors that shape attitudes towards Philippine English and contribute to a better understanding of language attitudes in multilingual societies. Both quantitative and qualitative methods were employed in the study, specifically the concurrent triangulation or convergent parallel design. The researchers used convenience sampling to identify 40 ESL teachers in selected provinces in Central Luzon, Philippines. The research instrument that the proponents utilized for this study is the survey questionnaire, and the data were analyzed through descriptive statistics and thematic analysis. Based on the quantitative findings, the data revealed that most ESL teachers strongly agree with the acceptance and utility of Philippine English in ESL instruction. Furthermore, the qualitative data presented that Philippine English promotes cultural understanding, student engagement, language empowerment, and a sense of belonging. It also enhances language skills, promotes cultural relevance and understanding, boosts communication and confidence, facilitates real-life application, and contributes to the professional growth of teachers. Finally, incorporating Philippine English in ESL instruction contributes to a more inclusive, engaging, and effective language learning experience for students. The researchers recommended offering professional development opportunities for ESL teachers, addressing the concerns of teachers who express disagreement and doubt regarding the utility of Philippine English, supporting teachers in adapting their teaching methods to effectively incorporate Philippine English, and encouraging ongoing professional growth and development among teachers in the field of Philippine English for ESL education. [ABSTRACT FROM AUTHOR]

Huntington's disease (HD) is a progressive neurodegenerative disorder caused by a CAG trinucleotide repeat expansion in the huntingtin (HTT) gene, which encodes a polyglutamine tract in the HTT protein. We found that peroxisome proliferator- activated receptor delta (PPAR-δ) interacts with HTT and that mutant HTT represses PPAR-δ-mediated transactivation. Increased PPAR-δ transactivation ameliorated mitochondrial dysfunction and improved cell survival of neurons from mouse models of HD. Expression of dominant-negative PPAR-δ in the central nervous system of mice was sufficient to induce motor dysfunction, neurodegeneration, mitochondrial abnormalities and transcriptional alterations that recapitulated HD-like phenotypes. Expression of dominant-negative PPAR-δ specifically in the striatum of medium spiny neurons in mice yielded HD- like motor phenotypes, accompanied by striatal neuron loss. In mouse models of HD, pharmacologic activation of PPAR-δ using the agonist KD3010 improved motor function, reduced neurodegeneration and increased survival. PPAR-δ activation also reduced HTT-induced neurotoxicity in vitro and in medium spiny-like neurons generated from stem cells derived from individuals with HD, indicating that PPAR-δ activation may be beneficial in HD and related disorders., The PPARs are ligand-activated transcription factors that belong to the nuclear hormone receptor superfamily. The three subtypes--termed PPAR-α, PPAR-δ and PPAR-γ--serve as lipid sensors in response to increased energy requirements [...]

Sulphide oxidation coupled to carbonate dissolution can provide a transient source of carbon dioxide to Earth's atmosphere and so balance the Cenozoic increase in carbon dioxide consumption by silicate weathering, reconciling this increase with the need for mass balance in the long-term carbon cycle. Balancing the Cenozoic carbon budget It is thought that mountain uplift stimulated carbon dioxide consumption by silicate mineral weathering during the Cenozoic era, roughly spanning the past 66 million years, but there are no signs of a corresponding increase in volcanic carbon dioxide emissions that could balance the carbon budget. This paper suggests that some of the missing carbon dioxide could have been produced by coupled sulphide oxidation and carbonate dissolution, a process that may also have been accelerated in response to uplift. This hypothesis is consistent with isotopic records and may help explain the interactions between the long-term carbon cycle, tectonics, and Earth's climate. The observed stability of Earth's climate over millions of years is thought to depend on the rate of carbon dioxide (CO.sub.2) release from the solid Earth being balanced by the rate of CO.sub.2 consumption by silicate weathering.sup.1. During the Cenozoic era, spanning approximately the past 66 million years, the concurrent increases in the marine isotopic ratios of strontium, osmium and lithium.sup.2,3,4 suggest that extensive uplift of mountain ranges may have stimulated CO.sub.2 consumption by silicate weathering.sup.5, but reconstructions of sea-floor spreading.sup.6 do not indicate a corresponding increase in CO.sub.2 inputs from volcanic degassing. The resulting imbalance would have depleted the atmosphere of all CO.sub.2 within a few million years.sup.7. As a result, reconciling Cenozoic isotopic records with the need for mass balance in the long-term carbon cycle has been a major and unresolved challenge in geochemistry and Earth history. Here we show that enhanced sulphide oxidation coupled to carbonate dissolution can provide a transient source of CO.sub.2 to Earth's atmosphere that is relevant over geological timescales. Like drawdown by means of silicate weathering, this source is probably enhanced by tectonic uplift, and so may have contributed to the relative stability of the partial pressure of atmospheric CO.sub.2 during the Cenozoic. A variety of other hypotheses.sup.8,9,10 have been put forward to explain the 'Cenozoic isotope-weathering paradox', and the evolution of the carbon cycle probably depended on multiple processes. However, an important role for sulphide oxidation coupled to carbonate dissolution is consistent with records of radiogenic isotopes.sup.2,3, atmospheric CO.sub.2 partial pressure.sup.11,12 and the evolution of the Cenozoic sulphur cycle, and could be accounted for by geologically reasonable changes in the global dioxygen cycle, suggesting that this CO.sub.2 source should be considered a potentially important but as yet generally unrecognized component of the long-term carbon cycle., Author(s): Mark A. Torres [sup.1] , A. Joshua West [sup.1] , Gaojun Li [sup.2] Author Affiliations: (1) Department of Earth Sciences, University of Southern California, Los Angeles, USA (2) Department [...]