It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Wednesday, January 29, 2025
National and gender differences in exclusionary behavior
When given the power to distribute resources, a person’s nationality, gender, and ideology can help predict how likely that person is to exclude others to maximize their own profit, according to a study. The results suggest that the identities and cultural backgrounds of decision-makers affect how equitably resources are divided.
Andrzej Baranski and Nicholas Haas placed study participants into groups of three to play a negotiation game. All interactions were via computer and no information about the other participants, such as names, ages, or genders was shared. A randomly chosen player was asked to propose a division for a fixed amount of money. As long as one other player approved of the division, the payout would proceed along the proposed lines. Players could propose a three-way split, or something like a 60%/40%/0% split, which might be acceptable to the player receiving 40% and net the proposer almost twice as much. The experiment was repeated in Australia, Austria, China, Colombia, Denmark, Egypt, Germany, Guatemala, Japan, Kenya, Spain, United Kingdom, United States, and Uruguay. In total, there were 1,485 participants, all university students. The most egalitarian nation was Austria, where just under 20% of negotiations ended in exclusionary alliances. In China, 70% of negotiations resulted in exclusionary alliances. In the United States, around 54% of negotiations resulted in exclusionary alliances. The best predictor for a high rate of exclusionary alliances was a high national score on the Hierarchy Tolerance Index, which attempts to quantify cultural acceptance of power inequalities. Men and ideologically right-wing participants were more likely to propose unequal splits than women and ideologically left-wing participants. All-male groups were 45% more likely to form an exclusionary alliance compared to all-female groups. According to the authors, ensuring gender equity in decision-making bodies may increase equality and inclusion in the distribution of resources.
Journal
PNAS Nexus
Article Title
Exclusionary bargaining behavior in 14 countries: Prevalence and predictors
Article Publication Date
28-Jan-2025
Plant-based substitute for fossil fuels developed for plastic foams
PULLMAN, Wash. — An environmentally-friendly preparation of plant material from pine could serve as a substitute for petroleum-based chemicals in polyurethane foams.
The innovation could lead to more environmentally friendly versions of foams used ubiquitously in products such as kitchen sponges, foam cushions, coatings, adhesives, packaging and insulation. The global market for polyurethane totaled more than $75 billion in 2022.
A Washington State University-led research team used an environmentally-friendly preparation of lignin as a substitute for 20% of the fossil fuel-based chemicals in the foam. The bio-based foam was as strong and flexible as typical polyurethane foam. They report on their work in the journal, ACS Sustainable Chemistry and Engineering.
“It’s quite novel in terms of the material we generate and the process we have,” said Xiao Zhang, corresponding author on the paper and professor in the Gene and Linda Voiland School of Chemical Engineering and Bioengineering. “Our extracted lignin offers a new class of renewable building blocks for the development of bio-based value-added products.”
Petroleum-based plastic materials are an increasing waste problem. They take centuries to break down, but they are expensive and difficult to recycle, most often producing an inferior second-generation product. Because it costs more to recycle than to generate new plastic, the plastics recycling rate has consistently stayed below 20%, said Zhang.
“It’s basically a no-win situation if you’re using petroleum-based plastics,” he said. “The ultimate solution is to replace them with naturally derived materials.”
Lignin is the second most abundant renewable carbon source, making up about 30% of the non-fossil fuel-based carbon on Earth. It is also notoriously difficult to extract from plants. The material is usually separated during papermaking and biorefining, but these processes often contaminate and significantly alter its chemical and physical properties, decreasing its value. So most lignin is either burned to produce fuel and electricity or used in low-value products, such as for cement additives or as a binder in animal feed.
In their work, the researchers used a mild, environmentally friendly solvent to separate a high-quality lignin from pine. Compared to other lignin formulations, their formulation was homogenous with good thermal stability — similar to native lignin. The structural homogeneity is important in being able to produce high-value products.
When they tested their formulation, their product was stable and performed as well mechanically as the conventional foams.
“This work demonstrates that our prepared lignin formulation has a great potential for generating flexible, bio-based polyurethane foams,” said Zhang.
The interest in developing lignin-based polyurethane (PU) flexible foam work was also validated by industrial partners. Zhang’s team will now work with the industrial partners to optimize and scale up lignin PU foam production.
The work was funded by the National Science Foundation’s Industry-University Cooperative Research Center for Bioplastics and Biocomposites (CB2), the USDA National Institute of Food and Agriculture programs, and WSU’s Office of Commercialization.
Adopting paywalls subtly shapes newspaper coverage, according to a study. Online journalism is increasingly found behind paywalls, as outlets pivot from funding their operations by selling ads to relying on subscriptions for revenue. This shift has raised questions about how newspapers might adjust their coverage to cater to paid subscribers' desires for popular news and soft news—entertainment, lifestyle, sports, and human-interest stories—at the expense of providing local news and maintaining democratic accountability. Paramveer S. Dhillon and colleagues quantified how coverage shifted after 17 major regional newspapers in the US adopted paywalls between 2006 and 2022. On average, papers published 5.1% less local news after adopting paywalls, which the authors interpret as a strategic shift toward more popular content. Perhaps surprisingly, many papers published less soft news after adopting paywalls, though the average decline—just 2.2%—was modest. Other effects were variable depending on market, reflecting newspapers' strategic adaptations to different urban contexts and demographics. Smaller cities (population below 500,000) saw a steeper decline in local news than average, suggesting a more pronounced realignment of content priorities under the new monetization strategy. Urban areas experiencing an influx of younger residents (below 40 years) saw a substantial, 19.1%, decline in local news, indicating newspapers' adaptive response to younger, digitally-oriented demographics. Notably, these same cities with younger readers increased their soft news coverage by 3.5%, reflecting newspapers' strategic efforts to cater to the content preferences of a younger, digital-savvy audience. According to the authors, the results reflect the difficult balancing act faced by newspapers attempting to achieve both financial sustainability and journalistic integrity. The authors argue that making the news appealing to paying customers could threaten the media’s democratic responsibilities.
Journal
PNAS Nexus
Article Title
How digital paywalls shape news coverage
Article Publication Date
28-Jan-2025
Climate change and the future of lignin production
How rising temperatures could impact a key natural resource
Credit: Department of Agricultural, Forest and Food Sciences, University of Torino, 10095 Grugliasco, Torino, Italy
This mini-review explores the influence of temperature on lignin deposition in plant cell walls, highlighting the need for adaptive strategies in lignin supply chains amidst global warming.
Lignin, a complex polymer found in plant cell walls, is the second most abundant organic substance in the plant kingdom after cellulose. It plays a crucial role in providing structural support and defense mechanisms in plants. Industrially, lignin is a by-product of the pulp and paper industry and is increasingly being explored for its potential in biofuels, bioplastics, and advanced materials. However, as global temperatures rise, the production and availability of lignin could be significantly impacted.
The study, titled "Environmental Impacts on Plant Cell Wall Lignification," reviews existing evidence suggesting that lignin deposition is constrained by low temperatures and enhanced by higher temperatures. This has significant implications for industries that rely on lignin, as climate change could alter the availability and characteristics of this resource.
The authors highlight that lignin biosynthesis is a critical evolutionary adaptation that allowed plants to thrive on land. Lignin not only provides mechanical strength but also protects plants from environmental stresses such as drought and herbivory. However, the impact of climate change on lignin production is multifaceted. While low temperatures inhibit lignification, high temperatures appear to promote it, although the latter effect requires further investigation.
The review emphasizes the need for adaptive strategies to ensure a resilient lignin supply chain. This includes understanding regional variations in lignin content, exploring alternative lignin sources, and developing climate-resilient plant varieties. Sustainable forestry and agricultural practices are also crucial in mitigating the impacts of global warming on lignin production.
The study concludes that adapting lignin supply to global warming requires a multifaceted approach involving scientific research, technological innovation, and supportive policy frameworks. By addressing these aspects comprehensively, industries can navigate the complexities of climate change and ensure a sustainable supply of lignin for various applications.
Environmental Impacts on Plant Cell Wall Lignification
Article Publication Date
26-Jan-2025
How can your houseplant survive up to a month and a half without watering?
The leaves of the ornamental never never plant can store water efficiently for up to 45 days thanks to their water-storing cell layers, and thus maintain their photosynthetic activity and chloroplast structure unchanged.
Never never plant with partially curled, drought-stressed leaves, with the the purple leaf coloration of the lower (abaxial) leaf side being exposed to the light
Hungarian researchers at ELTE Eötvös Loránd University and the HUN-REN Centre for Energy Research have shown that the leaves of the ornamental never never plant can store water efficiently for up to 45 days thanks to their water-storing cell layers, and thus maintain their photosynthetic activity and chloroplast structure unchanged. In collaboration with the Oak Ridge National Laboratory in Tennessee, they used small-angle neutron scattering measurements for the first time to investigate the structure of plastids in intact leaves of potted plants kept in completely natural conditions. Understanding the fundamental structural and functional processes that occur during drought stress and subsequent recovery could contribute to the long-term breeding of more drought-adapted crop plants.
The research highlights the additional regulatory mechanisms that allow this plant to maintain the structure and function of its photosynthetic apparatus virtually unchanged even after 45 days of water deficit. Their results show that the basic units of the photosynthetic membranes of the chloroplasts shrink by only 1 nm following water loss, but recover 18 hours after rewatering.
Drought and evolution: how long can plants adapt?
The evolutionary conquest of land posed a particular challenge for plants accustomed to aquatic environments, which had to adapt to many environmental factors, including in particular the need to survive even long periods without rainfall. Some species have developed specific strategies to survive these periods, but most of our economically important crops are sensitive to drought, which has become increasingly common in Hungary and worldwide in several regions in recent decades as a result of climate change.
Water scarcity negatively affects the metabolic processes of plants, including energy-producing photosynthesis, thereby affecting their growth and yields, and in extreme cases can lead to plant death. In the European Union and the United Kingdom alone, drought-related (field) economic losses are estimated at an average of €9 billion per year. Drought is viewed as one of the leading drivers of agricutural production risks. This makes it particularly important to study and understand the metabolism of plant species that are able to maintain photosynthetic activity and survive during extended periods of drought.
"The never never plant (Ctenanthe setosa) is a plant native to South America which is found as a houseplant or as an ornamental crop inside green walls or tropical-inspired buildings. We got them from the collection of the ELTE Botanical Garden. Because they can survive up to 45 or 60 days without watering, they are ideal for people who tend to forget to water their houseplants" notes Richard Hembrom, a PhD candidate from India and first author of the paper published on the subject. Thanks to a Stipendium Hungaricum scholarship, Richard, who is pursuing his doctoral studies at ELTE, has been studying how drought stress affects the structure and function of plant chloroplasts, particularly their photosynthetic activity.
The anatomy of drought tolerance
The research showed that although the water content of the plant's leaves gradually decreased with drought and the leaves became completely curled to reduce water loss by evaporation, the function and structure of the chloroplasts hardly changed during the long dry period. Below the upper (adaxial) and lower (abaxial) epidermis of the leaves, a special cell layer is located, which presumably plays a role in water storage, as this layer of cells on the upper side has thinned most significantly during the drought. The purplish colour of the lower (abaxial) leaf side is due to the presence of a pigment called anthocyanin, which may play a role in protecting the leaves from strong light when they are stressed and curled.
The structural analysis of plastids is particularly challenging under drought stress, as for electron microscopic analyses, most samples have to be prepared according to a complex protocol involving aqueous or other solvent phase solutions. Thus, it cannot be guaranteed that the typical state of the leaf under drought stress can be preserved during this time, and water added during sample preparation will not affect the results obtained or lead to artefacts. This issue is of particular interest, as in several articles other researchers have described, based on their electron microscopy studies, that the inner lumen of the sac-like, so-called thylakoid membranes in the chloroplasts swells under drought stress. However, swelling presumably requires water, of which there is very little in plant cells under such conditions, which sounds contradictional.
Resolving the contradiction - or the relationship between physicists, biologists and neutron scattering
The collaboration between ELTE plant biologists studying plants and physicists with expertise in small-angle neutron scattering measurements, also used in materials research, provided an excellent opportunity to resolve this controversy.
"When the plant leaf is placed in the neutron beam, the neutrons are scattered by its photosynthetic thylakoid membranes, the so-called grana, which consist of several layers of thylakoids piled on the top of each other in a regular arrangement. From the scattering pattern, it was possible to determine precisely the repeat distance value, that characterises the structure of the membranes and corresponds to the size of the repetitive basic units of grana. This value decreased from approx. 20 nm in the control plants to 19 nm in the dehydrated plants" explains Renáta Ünnep of the HUN-REN Energy Research Institute the main results of the measurement.
A similar decrease of the repeat distance values could be detected in electron microscopic images obtained and examined after conventional sample preparation. Both methods showed that there is a high biological variability between this nanoscale structure (repeat distance) of the grana present in different plants, in different leaves of the same plant and even in different regions of each leaf, and is therefore difficult to compare.
"The huge advantage of small-angle neutron scattering measurements in this case is that by placing a drought-stressed plant in the neutron beam of the world's most powerful accelerator-based neutron source in Tennessee, you can follow the changes in granum structure following rewetting at resolutions of minutes to hours. This allows us to observe how the repeat distance value of the granum gradually returns to around 20 nm 18 hours after rewatering" says Gergely Nagy of Oak Ridge National Laboratory in the US, who made these measurements. "Here, we are looking at the same grana in the same leaf region after a drought period and after rewatering. Whereas electron microscopy sampling is invasive, you have to cut a piece of leaf off, so in that case we can't follow the structural alterations of the same chloroplasts and grana in time and without any interference and sample preparation - only neutrons can do that," he adds.
Renáta Ünnep and Gergely Nagy have already investigated the plastids of many plants and algae using this method, and they have also had several previous collaborations with the Plastid Biology Laboratory led by Katalin Solymosi at the Department of Plant Anatomy at ELTE. However, this is the first time that the structure of the plastids of completely intact rooted and potted plants has been investigated using small-angle neutron scattering. In previous cases, cut leaves or leaf fragments were examined, and in many cases the samples were treated with heavy water (deuterium oxide) to obtain higher contrast and better signal. Fortunately, this was not necessary in the case of the never never plant, so that the leaves of the drought-stressed and then rewetted plant could be observed in their truly natural state.
"It is important to emphasize, however, that by examining a sufficient number of electron microscopic samples, we can reach similar conclusions as with neutrons. In addition to information about granum repeat distance values, electron microscopy also provides many further important details about the structure of the chloroplasts and the cells" notes Katalin Solymosi. "The two methods therefore tend to complement and reinforce each other, and clearly confirm that in this case, drying is indeed associated with shrinkage of the thylakoid membranes (grana) and rewetting with their expansion" concludes Katalin Solymosi.
A drought tolerant guide for future thinkers
In addition to the pioneering use of small angle neutron scattering for structural analysis in this work, the molecular organisation and function of the photosynthetic apparatus of the plant has been studied in detail. Further research is underway to better understand the additional regulatory mechanisms that allow this plant to maintain the structure and function of its photosynthetic apparatus virtually unchanged even after 45 days of water deficit.
Understanding these basic structural and functional processes could, in the long term, contribute to the breeding of more drought-adapted crops.
Data of the published paper: Richard Hembrom, Renáta Ünnep, Éva Sárvári, Gergely Nagy, Katalin Solymosi (2025) Dynamic in vivo monitoring of granum structural changes of Ctenanthe setosa (Roscoe) Eichler during drought stress and subsequent recovery. Physiologia Plantarum 177 (1) e14621. https://doi.org/10.1111/ppl.14621
never never plant’s leaf in a light microscope (left image) and a chloroplast in a transmission electron microscope
Cross-section of a never never plant’s leaf in a light microscope (left image) and a chloroplast in a transmission electron microscope (scale bar: 1 micrometre, stars: grana, arrows: plastid envelope membrane)
Structure of a granum (star) in an electron microscope (left, green arrow: envelope membrane, white arrow: stromal thylakoid) and a model demonstrating the repeat distance (basic unit of the granum)
