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The lichen is an ideal subject for student study because it is omnipresent in school yards, easily collected and observed year-round, a pioneer of evolution on land, and a bioindicator of air pollution. After doing fieldwork on this unusual composite organism as an apprentice with a team of lichenologists, Sarah Thorne developed Learning Lichens. This series of four lessons uses techniques of field study and data collection, classroom lab observation, and computer-based research. The lessons are most appropriate for biology or ecology classes in grades 11 and 12 but can be adapted for grades 9 or 10. In the lessons, Thorne's students learned basic identification skills, designed an inquiry-based field investigation, and wrote up the results of their research conducted in both the classroom and outdoors in school environs. During their investigations, students grew their own lichens and became protective, proud "parents" of them.

Terrestrial enhanced weathering (EW) of silicate rocks, such as crushed basalt, on farmlands is a promising scalable atmospheric carbon dioxide removal (CDR) strategy that urgently requires performance assessment with commercial farming practices. We report findings from a large-scale replicated EW field trial across a typical maize-soybean rotation on an experimental farm in the heart of the United Sates Corn Belt over 4 y (2016 to 2020). We show an average combined loss of major cations (Ca2+ and Mg2+) from crushed basalt applied each fall over 4 y (50 t ha-1 y-1) gave a conservative time-integrated cumulative CDR potential of 10.5 ± 3.8 t CO2 ha-1. Maize and soybean yields increased significantly (P < 0.05) by 12 to 16% with EW following improved soil fertility, decreased soil acidification, and upregulation of root nutrient transport genes. Yield enhancements with EW were achieved with significantly (P < 0.05) increased key micro- and macronutrient concentrations (including potassium, magnesium, manganese, phosphorus, and zinc), thus improving or maintaining crop nutritional status. We observed no significant increase in the content of trace metals in grains of maize or soybean or soil exchangeable pools relative to controls. Our findings suggest that widespread adoption of EW across farming sectors has the potential to contribute significantly to net-zero greenhouse gas emissions goals while simultaneously improving food and soil security. [ABSTRACT FROM AUTHOR]

In response to herbivory, many grasses, including crops such as wheat, accumulate significant levels of silicon (Si) as an antiherbivore defence. Damage-induced increases in Si can be localized in damaged leaves or be more systemic, but the mechanisms leading to these differences in Si distribution remain untested. Ten genetically diverse wheat landraces (Triticum aestivum) were used to assess genotypic variation in Si induction in response to mechanical damage and how this was affected by exogenous Si supply. Total and soluble Si levels were measured in damaged and undamaged leaves as well as in the phloem to test how Si was allocated to different parts of the plant after damage. Localized, but not systemic, induction of Si defences occurred, and was more pronounced when plants had supplemental Si. Damaged plants had significant increases in Si concentration in their damaged leaves, while the Si concentration in undamaged leaves decreased, such that there was no difference in the average Si concentration of damaged and undamaged plants. The increased Si in damaged leaves was due to the redirection of soluble Si, present in the phloem, from undamaged to damaged plant parts, potentially a more cost-effective defence mechanism for plants than increased Si uptake. [ABSTRACT FROM AUTHOR]

Functional trait distances between coexisting organisms reflect not only complementarity in the way they use resources, but also differences in their competitive abilities. Accordingly, absolute and relative trait distances have been widely used to capture the effects of niche dissimilarity and competitive hierarchies, respectively, on the performance of plants in competition. However, multiple dimensions of the plant phenotype are involved in these plant–plant interactions (PPI), challenging the use of relative trait distances to predict their outcomes. Furthermore, estimating the effects of competitive hierarchy on the performance of a group of coexisting plants remains particularly difficult since relative trait distances relate to the effects of a focal plant on another.We argue that trait distinctiveness, an emerging facet of functional diversity that characterizes the eccentric position of a species (or genotype) in a phenotypic space, can reveal the unique role played by a given individual plant in a group of competing plants. We used the model crop species Oryza sativa spp. japonica to evaluate the ability of trait distances and trait distinctiveness to predict the outcome of intraspecific PPI on the performance of single genotype and genotype mixtures. We performed a screening experiment to characterize the phenotypic space of 49 rice genotypes based on 11 above‐ground and root traits. We selected nine genotypes with contrasting positions in the phenotypic space and grew them in pots following a complete pairwise interaction design.Relative distances and distinctiveness based on traits associated with light competition were by far the best predictors of the performance of single genotypes—taller genotypes that acquired resource faster being the best competitors—while absolute trait distances had no effect. These results indicate that competitive hierarchy for light dominates PPI in this experiment. Consistently, trait distinctiveness in plant height and age at flowering had the strongest, positive effects on mixture performance, confirming that functional distinctiveness captures the effects of trait hierarchies and asymmetric PPI at this scale.Our findings shed new light on the role of trait diversity in regulating PPI and ecosystem processes and call for a greater consideration of functional distinctiveness in studies of coexistence mechanisms. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Plant ecologists and molecular biologists have long considered the hypothesis of a trade-off between plant growth and defence separately. In particular, how genes thought to control the growth–defence trade-off at the molecular level relate to trait-based frameworks in functional ecology, such as the slow–fast plant economics spectrum, is unknown. We grew 49 phenotypically diverse rice genotypes in pots under optimal conditions and measured growth-related functional traits and the constitutive expression of 11 genes involved in plant defence. We also quantified the concentration of silicon (Si) in leaves to estimate silica-based defences. Rice genotypes were aligned along a slow–fast continuum, with slow-growing, late-flowering genotypes versus fast-growing, early-flowering genotypes. Leaf dry matter content and leaf Si concentrations were not aligned with this axis and negatively correlated with each other. Live-fast genotypes exhibited greater expression of OsNPR1 , a regulator of the salicylic acid pathway that promotes plant defence while suppressing plant growth. These genotypes also exhibited greater expression of SPL7 and GH3.2 , which are also involved in both stress resistance and growth. Our results do not support the hypothesis of a growth–defence trade-off when leaf Si and leaf dry matter content are considered, but they do when hormonal pathway genes are considered. We demonstrate the benefits of combining ecological and molecular approaches to elucidate the growth–defence trade-off, opening new avenues for plant breeding and crop science. [ABSTRACT FROM AUTHOR]

Several articles are presented that explore some of the directions and applications of psychoanalytic theory in the field of communication studies. They include "Consciousness: A Missing Link in the Coupling of Technology and Communication" by Farrel Corcoran in the 1984 issue, "An Archive of the (Political) Unconscious" by Christopher Faulkner in the 2011 issue, and "That's Me: Nationalism and Identity on Balkan Reality TV" by Zala Volcic and Mark Andrejevic in the 2009 issue.

Estimating plasticity of leaf silicon (Si) in response to abiotic and biotic factors underpins our comprehension of plant defences and stress resistance in natural and agroecosystems. However, how nitrogen (N) addition and intraspecific plant–plant interactions affect Si concentration remains unclear.We grew 19 durum wheat genotypes (Triticum turgidum ssp. durum) in pots, either alone or in intra‐ or intergenotypic cultures of two individuals, and with or without N. Above‐ground biomass, plant height and leaf [Si] were quantified at the beginning of the flowering stage.Nitrogen addition decreased leaf [Si] for most genotypes, proportionally to the biomass increase. Si plasticity to plant–plant interactions varied significantly among genotypes, with both increases and decreases in leaf [Si] when mixed with a neighbour, regardless of the mixture type (intra‐/intergenotype). Besides, increased leaf [Si] in response to plant–plant interactions was associated with increased plant height.Our results suggest the occurrence of both facilitation and competition for Si uptake from the rhizosphere in wheat mixtures. Future research should identify which leaf and root traits characterise facilitating neighbours for Si acquisition. We also show that Si could be involved in height gain in response to intraspecific competition, possibly for increasing light capture. This important finding opens up new research directions on Si and plant–plant interactions in both natural ecosystems and agroecosystems. More generally, our results stress the need to explore leaf Si plasticity in responses to both abiotic and biotic factors to understand plant stress resistance. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

In recent years, a growing list of content creators have published videos announcing that they are leaving YouTube, taking a break, or reducing their upload schedule (Alexander). Many of these young creators state that their decision resulted from burnout, caused by a relentless schedule and obsession with YouTube's algorithm and analytics -- tools essential to success on this highly competitive creative platform (Srnicek). Its opaque algorithm, however, induces anxiety; an affect described as that which "arises when the subject is confronted by the desire of the Other and does not know what object he is for that desire" (Evans 12). Here, the Other is conflated as both audience and algorithm, insofar as what videos trend or are recommended is a complex merging of user-engagement and vetting by the algorithm. Attempting to discover the desire of the Other, creators examine data to speculate about what content will gain the most views. While some creators opt to chase trends and use clickbait titles, others avoid the algorithm's detection and suppression by omitting key words known to be flagged, while others embrace defeat and instead drive their channels using drama and negative affect (Berryman and Kavka). Drawing on Lacan's psychoanalytic clinical structures and theory of anxiety, this article examines how each of these approaches to navigating the platform represents a neurotic and sometimes perverse response to the algorithmic Other that is influenced by a neoliberal notion of creativity that privileges growth over its socially transformative power (Mould). [ABSTRACT FROM AUTHOR]

Ontario, Canada's Hydro One Networks dealt successfully with electricity transmission deregulation by involving stakeholders in rate setting.?

Normal faults are commonly segmented along strike, with segments that localize strain and influence propagation of slip during earthquakes. Although the geometry of segments can be constrained by fault mapping, it is challenging to determine seismically relevant segments along a fault zone. Because slip histories, geometries, and strengths of linkages between normal fault segments fundamentally control the propagation of rupture during earthquakes, and differences in segment slip rates result in differential uplift of adjacent footwalls, we used along-strike changes in footwall morphology to detect fault segments and the relative strength of the mechanical links between them. We applied a new geomorphic analysis protocol to the Wassuk Range fault, Nevada, within the actively deforming Walker Lane. The protocol examines characteristics of footwall morphology, including range-crest continuity, bedrock-channel long profiles, catchment area variability, and footwall relief, to detect changes in strike-parallel footwall characteristics. Results revealed six domains with significant differences in morphology that we used to identify seismically relevant fault segments and segment boundaries. We integrated our results with previous studies to determine relative strength of links between the six segments, informing seismic hazard assessment. When combined with recent geodetic studies, our results have implications for the future evolution of the Walker Lane, suggesting changes in the accommodation of strain across the region. Our analysis demonstrates the power of this method to efficiently detect along-strike changes in footwall morphology related to fault behavior, permitting future researchers to perform reconnaissance assessment of normal fault segmentation worldwide. [ABSTRACT FROM AUTHOR]

Salinity affects around 20% of all arable land while an even larger area suffers from recurrent drought. Together these stresses suppress global crop production by as much as 50% and their impacts are predicted to be exacerbated by climate change. Infrastructure and management practices can mitigate these detrimental impacts, but are costly. Crop breeding for improved tolerance has had some success but is progressing slowly and is not keeping pace with climate change. In contrast, Silicon (Si) is known to improve plant tolerance to a range of stresses and could provide a sustainable, rapid and cost-effective mitigation method. The exact mechanisms are still under debate but it appears Si can relieve salt stress via accumulation in the root apoplast where it reduces "bypass flow of ions to the shoot. Si-dependent drought relief has been linked to lowered root hydraulic conductance and reduction of water loss through transpiration. However, many alternative mechanisms may play a role such as altered gene expression and increased accumulation of compatible solutes. Oxidative damage that occurs under stress conditions can be reduced by Si through increased antioxidative enzymes while Si-improved photosynthesis has also been reported. Si fertilizer can be produced relatively cheaply and to assess its economic viability to improve crop stress tolerance we present a cost-benefit analysis. It suggests that Si fertilization may be beneficial in many agronomic settings but may be beyond the means of smallholder farmers in developing countries. Si application may also have disadvantages, such as increased soil pH, less efficient conversion of crops into biofuel and reduced digestibility of animal fodder. These issues may hamper uptake of Si fertilization as a routine agronomic practice. Here, we critically evaluate recent literature, quantifying the most significant physiological changes associated with Si in plants under drought and salinity stress. Analyses show that metrics associated with photosynthesis, water balance and oxidative stress all improve when Si is present during plant exposure to salinity and drought. We further conclude that most of these changes can be explained by apoplastic roles of Si while there is as yet little evidence to support biochemical roles of this element. [ABSTRACT FROM AUTHOR]

Surveying narrative applications of artificial intelligence in film, games and interactive fiction, this article imagines the future of artificial intelligence (AI) authorship and explores trends that seek to replace human authors with algorithmically generated narrative. While experimental works that draw on text generation and natural language processing have a rich history, this article focuses on commercial applications of AI narrative and looks to future applications of this technology. Video games have incorporated AI and procedural generation for many years, but more recently, new applications of this technology have emerged in other media. Director Oscar Sharp and artist Ross Goodwin, for example, generated significant media buzz about two short films that they produced which were written by their AI screenwriter. It's No Game (2017), in particular, offers an apt commentary on the possibility of replacing striking screenwriters with AI authors. Increasingly, AI agents and virtual assistants like Siri, Cortana, Alexa and Google Assistant are incorporated into our daily lives. As concerns about their eavesdropping circulate in news media, it is clear that these companions are learning a lot about us, which raises concerns about how our data might be employed in the future. This article explores current applications of AI for storytelling and future directions of this technology to offer insight into issues that have and will continue to arise as AI storytelling advances. [ABSTRACT FROM AUTHOR]

Drought stress reduces annual global wheat yields by 20%. Silicon (Si) fertilisation has been proposed to improve plant drought stress tolerance. However, it is currently unknown if and how Si affects different wheat landraces, especially with respect to their innate Si accumulation properties. In this study, significant and consistent differences in Si accumulation between landraces were identified, allowing for the classification of high Si accumulators and low Si accumulators. Landraces from the two accumulation groups were then used to investigate the effect of Si during osmotic and drought stress. Si was found to improve growth marginally in high Si accumulators during osmotic stress. However, no significant effect of Si on growth during drought stress was found. It was further found that osmotic stress decreased Si accumulation for all landraces whereas drought increased it. Overall, these results suggest that the beneficial effect of Si commonly reported in similar studies is not universal and that the application of Si fertiliser as a solution to agricultural drought stress requires detailed understanding of genotype-specific responses to Si. [ABSTRACT FROM AUTHOR]

Plant ecologists and molecular biologists have long considered the hypothesis of a trade-off between plant growth and defence separately. In particular, how genes thought to control the growth-defence trade-off at the molecular level relate to trait-based frameworks in functional ecology, such as the slow-fast plant economics spectrum, is unknown. We grew 49 phenotypically diverse rice genotypes in pots under optimal conditions and measured growth-related functional traits and the constitutive expression of 11 genes involved in plant defence. We also quantified the concentration of silicon (Si) in leaves to estimate silica-based defences. Rice genotypes were aligned along a slow-fast continuum, with slow-growing, late-flowering genotypes versus fast-growing, early-flowering genotypes. Leaf dry matter content and leaf Si concentrations were not aligned with this axis and negatively correlated with each other. Live-fast genotypes exhibited greater expression of OsNPR1, a regulator of the salicylic acid pathway that promotes plant defence while suppressing plant growth. These genotypes also exhibited greater expression of SPL7 and GH3.2, which are also involved in both stress resistance and growth. Our results do not support the hypothesis of a growth-defence trade-off when leaf Si and leaf dry matter content are considered, but they do when hormonal pathway genes are considered. We demonstrate the benefits of combining ecological and molecular approaches to elucidate the growth-defence trade-off, opening new avenues for plant breeding and crop science., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Society for Experimental Biology.)

Background: Research was conducted to gain insight into potential clients' decisions to undergo plastic surgery, their perception of benefits and risks, their judgment of outcomes, and their selection of a plastic surgeon., Methods: Semistructured, open-ended interviews were conducted with 60 people who expressed interest in plastic surgery. Qualitative analysis revealed their "mental models" regarding influences on their decision to undergo plastic surgery and their choice of a surgeon. Interview results were used to design a Web-based survey in which 644 individuals considering plastic surgery responded., Results: The desire for change was the most direct motivator to undergo plastic surgery. Improvements to physical well-being were related to emotional and social benefits. When prompted about risks, participants mentioned physical, emotional, and social risks. Surgeon selection was a critical influence on decisions to undergo plastic surgery. Participants gave considerable weight to personal consultation and believed that finding the "right" plastic surgeon would minimize potential risks. Findings from the Web-based survey were similar to the mental models interviews in terms of benefit ratings but differed in risk ratings and surgeon selection criteria., Conclusions: The mental models interviews revealed that interview participants were thoughtful about their decision to undergo plastic surgery and focused on finding the right plastic surgeon.