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Phytolith is widely known as a silica structure in numerous silicon (Si) accumulator plants, e.g., rice, and it contains various nutrients and other beneficial elements. When rice straw is returned to paddy fields, the silica structure of phytolith can be dissolved, thereby releasing its occluded nutrients. While the intrinsic characteristics and dissolution properties of phytoliths under the effect of solution chemistry have been intensively studied, the effect of gas phases, especially CO2, on phytolith stability and the implications for nutrient release are not fully known. Here, dissolution properties of phytolith ashes obtained from dry ashing of rice straw at 400, 600 and 800 °C were investigated by quantifying Si release together with other nutrients under two atmospheric conditions, i.e., without and with CO2 support (aeration). In a time span of 6 days, the releases of nutrients (K, P, Ca, Mg) showed high dependence on the overall dissolution of the phytolith ashes. CO2 significantly reduced the dissolution rate of the phytolith ashes but increased the release rates of cationic as well as anionic nutrients. The aeration of CO2 shifted the carbonate equilibrium (H2CO3, HCO3− and CO32−) towards H2CO3, reducing solution pH, thereby decreasing the dissolution rate of phytoliths. Following this, intensification of H+ exchange promoted nutrient releases from the phytolith ashes. This indicates contrasted responses of phytoliths and their occluded nutrients to CO2, and provides a better insight on the fate of soil phytoliths and the tendency of nutrient budgets from rice straw phytoliths in soils. [ABSTRACT FROM AUTHOR]

Rice production helps feed at least half of the world's population but generates approximately one billion tonnes of straw residue per annum. On-site open burning of rice straw after harvesting is common in recent times because there has been less demand for rice straw to use as fuel and fodder. Due to health and climate change concerns, open burning, which results in biomass losses, smog and emissions of green house gases, e.g., CO2, has been widely criticized and banned in many countries. Little is known about the positive benefits of straw burning, such as field care (eradication of biotic diseases) or nutrient cycling. Herein, we propose a new viewpoint in which the burning of rice straw followed by cycling of the burned materials, including silica material (so-called phytolith), into soil is demonstrated as a CO2-sequestration strategy via buffering the soil CO2 flux and coupling CO2 with the silicon cycle. [ABSTRACT FROM AUTHOR]

We acquire a lot of information about the world through texts, which can be categorized at the broadest level into two primary genres: narratives and exposition. Stories and essays differ across a variety of dimensions, including structure and content, with numerous theories hypothesizing that stories are easier to understand and recall than essays. However, empirical work in this area has yielded mixed results. To synthesize research in this area, we conducted a meta-analysis of experiments in which memory and/or comprehension of narrative and expository texts was investigated. Based on over 75 unique samples and data from more than 33,000 participants, we found that stories were more easily understood and better recalled than essays. Moreover, this result was robust, not influenced by the inclusion of a single effect-size or single study, and not moderated by various study characteristics. This finding has implications for any domain in which acquiring and retaining information is important. [ABSTRACT FROM AUTHOR]

Chromatin immunoprecipitation assays have contributed greatly to our understanding of the role of histone modifications in gene regulation. However, they do not permit analysis with single-cell resolution, thus confounding analyses of heterogeneous cell populations. Here we present a method that permits visualization of histone modifications of single genomic loci with single-cell resolution in formaldehyde-fixed paraffin-embedded tissue sections based on combined use of in situ hybridization and proximity ligation assays. We show that dimethylation of lysine 4 of histone H3 (H3K4me2) at the MYH11 locus is restricted to the smooth muscle cell (SMC) lineage in human and mouse tissue sections and that the mark persists even in phenotypically modulated SMC in atherosclerotic lesions that show no detectable expression of SMC marker genes. This methodology has promise for broad applications in the study of epigenetic mechanisms in complex multicellular tissues in development and disease. [ABSTRACT FROM AUTHOR]

Despite intense interest in designing positive allosteric modulators (PAMs) as selective drugs of the adenosine A1 receptor (A1AR), structural binding modes of the receptor PAMs remain unknown. Using the first X-ray structure of the A1AR, we have performed all-atom simulations using a robust Gaussian accelerated molecular dynamics (GaMD) technique to determine binding modes of the A1AR allosteric drug leads. Two prototypical PAMs, PD81723 and VCP171, were selected. Each PAM was initially placed at least 20 Å away from the receptor. Extensive GaMD simulations using the AMBER and NAMD simulation packages at different acceleration levels captured spontaneous binding of PAMs to the A1AR. The simulations allowed us to identify low-energy binding modes of the PAMs at an allosteric site formed by the receptor extracellular loop 2 (ECL2), which are highly consistent with mutagenesis experimental data. Furthermore, the PAMs stabilized agonist binding in the receptor. In the absence of PAMs at the ECL2 allosteric site, the agonist sampled a significantly larger conformational space and even dissociated from the A1AR alone. In summary, the GaMD simulations elucidated structural binding modes of the PAMs and provided important insights into allostery in the A1AR, which will greatly facilitate the receptor structure-based drug design. [ABSTRACT FROM AUTHOR]

This study describes trends in the supply and the need for behavioral health professionals in Nebraska. A state-level health workforce database was used to estimate the behavioral health workforce supply and need. Compared with national estimates, Nebraska has a lower proportion of all categories of behavioral health professionals. The majority of Nebraska counties have unusually high needs for mental health professionals, with rural areas experiencing a decline in the supply of psychiatrists over the last decade. Availability of robust state-level health workforce data can assist in crafting effective policy for successful systems change, particularly for behavioral health. [ABSTRACT FROM AUTHOR]

Retinitis pigmentosa (RP) is a degenerative retinal disease involving progressive loss of rod and cone photoreceptor function. It represents the most common form of registered blindness among the working aged populations of developed countries. Given the immense genetic heterogeneity associated with this disease, parameters influencing cone photoreceptor survival (preservation of daytime vision) that are independent of primary mutations are exceedingly important to identify from a therapeutic standpoint. Here we identify C1q, the primary component of the classical complement pathway, as a cone photoreceptor neuronal survival factor. [ABSTRACT FROM AUTHOR]