What math can teach us about standing up to bullies

Game theory study shows that being uncooperative gives weaker parties the upper hand

Peer-Reviewed Publication

DARTMOUTH COLLEGE

In a time of income inequality and ruthless politics, people with outsized power or an unrelenting willingness to browbeat others often seem to come out ahead.

New research from Dartmouth, however, shows that being uncooperative can help people on the weaker side of the power dynamic achieve a more equal outcome—and even inflict some loss on their abusive counterpart.

The findings provide a tool based in game theory—the field of mathematics focused on optimizing competitive strategies—that could be applied to help equalize the balance of power in labor negotiations or international relations and could even be used to integrate cooperation into interconnected artificial intelligence systems such as driverless cars.

Published in the latest issue of the journal PNAS Nexus, the study takes a fresh look at what are known in game theory as "zero-determinant strategies" developed by renowned scientists William Press, now at the University of Texas at Austin, and the late Freeman Dyson at the Institute for Advanced Study in Princeton, New Jersey.

Zero-determinant strategies dictate that "extortionists" control situations to their advantage by becoming less and less cooperative—though just cooperative enough to keep the other party engaged—and by never being the first to concede when there's a stalemate. Theoretically, they will always outperform their opponent by demanding and receiving a larger share of what's at stake.

But the Dartmouth paper uses mathematical models of interactions to uncover an "Achilles heel" to these seemingly uncrackable scenarios, said senior author Feng Fu, an associate professor of mathematics. Fu and first author Xingru Chen, who received her Ph.D. in mathematics from Dartmouth in 2021, discovered an "unbending strategy" in which resistance to being steamrolled not only causes an extortionist to ultimately lose more than their opponent but can result in a more equal outcome as the overbearing party compromises in a scramble to get the best payoff.

"Unbending players who choose not to be extorted can resist by refusing to fully cooperate. They also give up part of their own payoff, but the extortioner loses even more," said Chen, who is now an assistant professor at the Beijing University of Posts and Telecommunications.

"Our work shows that when an extortioner is faced with an unbending player, their best response is to offer a fair split, thereby guaranteeing an equal payoff for both parties," she said. "In other words, fairness and cooperation can be cultivated and enforced by unbending players."

These scenarios frequently play out in the real world, Fu said. Labor relations provide a poignant model. A large corporation can strong-arm suppliers and producers such as farmworkers to accept lower prices for their effort by threatening to replace them and cut them off from a lucrative market. But a strike or protest can turn the balance of power back toward the workers' favor and result in more fairness and cooperation, such as when a labor union wins some concessions from an employer.

While the power dynamic in these scenarios is never equal, Fu said, his and Chen's work shows that unbending players can reap benefits by defecting from time to time and sabotaging what extortioners are truly after—the highest payoff for themselves.

"The practical insight from our work is for weaker parties to be unbending and resist being the first to compromise, thereby transforming the interaction into an ultimatum game in which extortioners are incentivized to be fairer and more cooperative to avoid 'lose-lose' situations," Fu said.

"Consider the dynamics of power between dominant entities such as Donald Trump and the lack of unbending from the Republican Party, or, on the other hand, the military and political resistance to Russia's invasion of Ukraine that has helped counteract incredible asymmetry," he said. "These results can be applied to real-world situations, from social equity and fair pay to developing systems that promote cooperation among AI agents, such as autonomous driving."

Chen and Fu's paper expands the theoretical understanding of zero-determinant interactions while also outlining how the outsized power of extortioners can be checked, said mathematician Christian Hilbe, leader of the Dynamics of Social Behavior research group at the Max Planck Institute for Evolutionary Biology in Germany

"Among the technical contributions, they stress that even extortioners can be outperformed in some games. I don't think that has been fully appreciated by the community before," said Hilbe, who was not involved in the study but is familiar with it. "Among the conceptual insights, I like the idea of unbending strategies, behaviors that encourage an extortionate player to eventually settle at a fairer outcome."

Behavioral research involving human participants has shown that extortioners may constitute a significant portion of our everyday interactions, said Hilbe, who published a 2016 paper in the journal PLOS ONE reporting just that. He also co-authored a 2014 study in Nature Communications that found people playing against a computerized opponent strongly resisted when the computer engaged in threatening conduct, even when it reduced their own payout.

"The empirical evidence to date suggests that people do engage in these extortionate behaviors, especially in asymmetric situations, and that the extorted party often tries to resist it, which is then costly to both parties," Hilbe said.

The paper, "Outlearning extortioners: Unbending strategies can foster reciprocal fairness and cooperation," is published in the June 2023 issue of PNAS Nexus. The work was supported by the Beijing University of Posts and Telecommunications; the Bill and Melinda Gates Foundation (OPP1217336); the National Institutes of Health's Centers of Biomedical Research Excellence (COBRE) Program (1P20GM130454); a CompX Faculty Grant from the Neukom Institute for Computational Science at Dartmouth; the Dartmouth Faculty Startup Fund; and a Walter and Constance Burke Research Initiation Award from Dartmouth.

JOURNAL

PNAS Nexus

DOI

10.1093/pnasnexus/pgad176 

METHOD OF RESEARCH

Computational simulation/modeling

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Outlearning extortioners: unbending strategies can foster reciprocal fairness and cooperation

Can re-imagining old technology help build a more sustainable future?

To pull back our demands on the planet, a sustainable design expert suggests we should be looking back to the future with our technology.

Book Announcement

TAYLOR & FRANCIS GROUP

An industrial designer has suggested that old technologies could make a comeback for a more sustainable future – such as wind-up shavers, pedal-powered tools and manual lawn mowers.

In his new book, Re-Imagining Alternative Technology, Brook S Kennedy envisions an innovative revival of underused and abandoned ideas, alongside new creative ones, to tackle global challenges such as climate change, natural resource management and pollution.

“With the global challenge of climate change, managing finite natural resources and pollution, everyone is focused on the biggest and most energy-hungry technologies. I’m suggesting that smaller, cumulative changes in our everyday lives could make a huge difference,” Kennedy explains.

“Rather than starting from scratch and face looking at an impossible task, I am suggesting design could focus on ‘modernizing’ technology we already know works. With some updating and refinement to aesthetics, performance and usability, these technologies could easily be brought back into re-use.”

Re-imagining nostalgic technologies

Kennedy is an award-winning industrial designer and Associate Professor in the School of Architecture, Arts and Design at Virginia Polytechnic Institute and State University (Virginia Tech), US.

There his research focuses on topics in sustainable design and materials, appropriate technology, and biodesign.

Some of the nostalgic technologies he believes could make a valuable comeback include passive wind-harnessing cooling systems and human-assisted powered tools and appliances, and reusable, repairable durable goods that have become disposable in today’s context.

He also makes the case for ‘reimagining’ other domestic appliances including examples like manual carpet-sweepers and water collectors, as well as advocating for a return to reusable, durable products such as razors you can sharpen and shoe soles you can re-sole and repair.

As well as looking to the past for inspiration, Kennedy also looks at warmer climates to see if we can learn from other cultures.

He explains: “If many of these so-called forgotten alternative technologies are still common and in use mainly outside the United States, why can’t we make some changes and apply them here?”

He suggests Persian wind catchers could be used as a passive and low-energy house-cooling technique, and fog-catchers like those used in Chile and Morocco could be adapted for large-scale water-harvesting.

For public transport, Kennedy suggests the popular bicycle highways of the 1900s, as seen in Pasadena, could make a comeback, as well as water-powered funicular trains and ferries.

“There are so many more examples in transportation, architecture, and product design. Designers could help bring contemporary relevance to passive and ecological technologies, from awnings, manual carpet sweepers and more, which would have a cumulative effect on energy consumption and waste across the built environment.”

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DOI

10.4324/9780367814304 

Laocoön and his sons in Frankfurt

A true-to-original copy of the ancient masterpiece is now a permanent installation in Goethe University Frankfurt’s Sculpture Hall

Business Announcement

GOETHE UNIVERSITY FRANKFURT

 

IMAGE: WEIGHTY ADDITION: THE TRUE-TO-ORIGINAL, APPROX. 260 KG CAST OF LAOCOÖN AND HIS SONS, PICTURED AFTER ITS ARRIVAL AT GOETHE UNIVERSITY’S SCULPTURE HALL. PICTURED HERE ARE ARTIST HANS EFFENBERGER (SECOND FROM LEFT), THE CURATOR OF THE COLLECTION OF CLASSICAL ANTIQUITIES AND THE SCULPTURE HALL MATTHIAS RECKE (RIGHT), AND RESEARCHERS FROM GOETHE UNIVERSITY’S ARCHAEOLOGICAL INSTITUTE, ALL OF WHOM WORKED TOGETHER TO ASSEMBLE THE STATUE FROM TWELVE INDIVIDUAL PARTS. (PHOTOS: OLIVER DZIEMBA/GOETHE UNIVERSITY) view more 

CREDIT: OLIVER DZIEMBA/GOETHE UNIVERSITY

Goethe University’s Sculpture Hall has received a prominent addition: a true-to-original copy of the monumental statue of Laocoön and his sons recently became part of the Collection of Classical Antiquities, bringing to Frankfurt one of the most important masterpieces of the Vatican Museums and certainly one of the most famous and influential ancient sculptures ever. The cast of the original artwork, kept in the Vatican, was custom-made for the Frankfurt collection. Making this unique project possible is a donation from York Thiel and Anni Heyrodt, a donor couple with close ties to classical archaeology in Frankfurt, who have generously supported the collection for years.

The sculpture will be handed over during a ceremony held on June 25, as part of one of the regular guided tours offered at the Sculpture Hall on Sundays. The event will also feature a lecture by Prof. Dr. Anja Klöckner and Dr. Matthias Recke (of Goethe University’s Institute for Archaeological Sciences), which will focus on the complexity of the work, its mass appeal and its reception up to the present day. The theme of the multi-figure group is taken from the popular myths surrounding the Trojan War: Apollo priest Laocoön warns the Trojans not to drag the wooden horse into the city – suspecting that doing so will seal the city's downfall. Roman poet Vergil describes how Laocoön and his sons are later attacked and killed by two enormous serpents sent by the goddess Athena.

Discovered in Rome as early as 1506, the three-figure original sculpture dating back to Roman times was completed in Michelangelo's workshop. The marble statue has had an immense influence on Renaissance art. To this day, the depiction of Laocoön, who, despite being entangled in the throes of death, also conveys tremendous dynamism, is considered one of antiquity’s greatest artistic creations.

With the Laocoön statue, the Frankfurt collection has received not only its first monumental figural group, the new acquisition also adds a new work from the period between the 1st century B.C. to the 1st century A.D., benefiting students of archaeology and art studies, among others.

Created by professional art shapers from the German city of Leipzig, the statue consists of twelve individual parts crafted from a mold taken directly from the marble original: It is made of plaster, partly mixed with glass fiber and jute, weighs about 260 kg and is 2.42 meters high (taking into account its 35 cm pedestal, its total height comes to 2.77 meters).

Weighty addition: The true-to-original, approx. 260 kg cast of Laocoön and His Sons, pictured after its arrival at Goethe University’s Sculpture Hall. Pictured here are artist Hans Effenberger (second from left), the curator of the Collection of Classical Antiquities and the Sculpture Hall Matthias Recke (right), and researchers from Goethe University’s Archaeological Institute, all of whom worked together to assemble the statue from twelve individual parts. (Photos: Oliver Dziemba/Goethe University)

Laocoön 3 (IMAGE)

GOETHE UNIVERSITY FRANKFURT

Weighty addition: The true-to-original, approx. 260 kg cast of Laocoön and His Sons, pictured after its arrival at Goethe University’s Sculpture Hall. Pictured here are artist Hans Effenberger (second from left), the curator of the Collection of Classical Antiquities and the Sculpture Hall Matthias Recke (right), and researchers from Goethe University’s Archaeological Institute, all of whom worked together to assemble the statue from twelve individual parts. (Photos: Oliver Dziemba/Goethe University)

Weighty addition: The true-to-original, approx. 260 kg cast of Laocoön and His Sons, pictured after its arrival at Goethe University’s Sculpture Hall. Pictured here are artist Hans Effenberger (second from left), the curator of the Collection of Classical Antiquities and the Sculpture Hall Matthias Recke (right), and researchers from Goethe University’s Archaeological Institute, all of whom worked together to assemble the statue from twelve individual parts. (Photos: Oliver Dziemba/Goethe University)

CREDIT

Oliver Dziemba/Goethe University

Projected land use changes in the Qinghai-Tibet Plateau at the carbon peak and carbon neutrality targets

Peer-Reviewed Publication

SCIENCE CHINA PRESS

 

IMAGE: A PAPER PUBLISHED IN SCIENCE CHINA: EARTH SCIENCES ESTIMATED THE LAND USE CHANGES ON THE TIBETAN PLATEAU DURING THE PEAK CARBON PERIOD (2021-2040), THE CARBON NEUTRAL PERIOD (2051-2070) AND THE END OF THE 21ST CENTURY (2081-2100) BASED ON SHARED SOCIO-ECONOMIC PATHWAYS (SSPS). THE LAND USE TRENDS AND LAND USE SHIFT CHARACTERISTICS OF THE QINGHAI-TIBET PLATEAU UNDER THE FUTURE "DOUBLE CARBON" TARGET WERE ESTIMATED. view more 

CREDIT: ©SCIENCE CHINA PRESS

Land use change is closely related to human activities, affecting ecological environment and species diversity, and how to make scientific observations and simulations to predict it has become a focal issue. The Qinghai-Tibet Plateau, known as the "third pole of the world", is extremely sensitive to global climate change. Its complex physical geography and unique social and human processes have made it a hot spot for global research. Land use change on the Tibetan Plateau is an important foundation of ecological security barrier, and it has significant impacts on the Tibetan Plateau, its surrounding regions and the world.

This study predicts land use changes in the Tibetan Plateau during the carbon peak (2021-2040), carbon neutral (2051-2070), and late 21st century (2081-2100) based on shared socioeconomic pathways (SSPs). In the base period (1995~2014), the areas of arable land, forest land, grassland, urban land and bare land on the Tibetan Plateau are about 14×103, 349×103, 1853×103, 0.3×103 and 235×103km2, respectively. compared with the base period, the area of grassland will decrease in the next three periods, and urban, forest land and bare land will increase. By the end of the 21st century, grassland will decrease by 6.1 to 21.7%, and woodland is the land use type with the largest increase in area, increasing by about 21.2 to 72.8%.

 

Xu R, Shi P, Gao M, Wang Y, Wang G, Su B, Huang J, Lin Q, Jiang T. 2023. Projected land use changes in the Qinghai-Tibet Plateau at the carbon peak and carbon neutrality targets. Science China Earth Sciences, 66(6): 1383–1398, https://doi.org/10.1007/s11430-022-1077-y

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JOURNAL

Science China Earth Sciences

DOI

10.1007/s11430-022-1077-y 

The release of DNA methylation map of four Chinese populations and epigenetic variation associated with Tibetans’ adaptation to Qinghai-Tibet Plateau

Peer-Reviewed Publication

SCIENCE CHINA PRESS

 

IMAGE: (A) THE GENETIC STRUCTURE OF THE POPULATION BASED ON POPULATION SNPS. (B) THE EPIGENETIC STRUCTURE OF THE POPULATION BASED ON ETHNIC-SPECIFIC DNA METHYLATION SITES. (C) THE DISTRIBUTION CURVE OF CORRELATION VALUES ESTIMATED BETWEEN OVERALL GENETIC DISTANCES AND CPG METHYLATION MANHATTAN DISTANCES OF CPGS SORTED WITH THE VALUES OF PST, THE PARAMETER TO ESTIMATE PHENOTYPIC DIFFERENTIATION BETWEEN POPULATIONS. (D-E) THE CORRELATION CURVES BASED ON THE BETWEEN-ETHNIC (D) OR WITHIN-ETHNIC (E) COMPARISON OF GENETIC DISTANCES WITH CPG METHYLATION MANHATTAN DISTANCES. view more 

CREDIT: ©SCIENCE CHINA PRESS

]

Recently, a paper entitled “Genome-wide DNA methylation landscape of four Chinese populations and epigenetic variation linked to Tibetan high-altitude adaptation” was published online in the journal SCIENCE CHINA Life Sciences. This study is led by Prof. Wen Wang (Northwestern Polytechnical University), Prof. Shuhua Xu (Fudan University), Prof. Zhengsheng Sun (Chinese Academy of Sciences), and associate Prof. Peng Tian (Northwest A&F University). Using the recently developed double strand bisulfite sequencing (DSBS) in Sun lab, this study revealed both genetic and DNA methylation variation in four Chinese ethnic groups, and investigated the potential difference and association of the two mechanisms in the population. Based on the comparison of Tibetan with other lowland individuals, they proposed potential function of epigenetic regulation in Tibetans’ adaptation to Qinghai-Tibet Plateau.

DNA methylation is one of the most important epigenetic marks in eukaryotic genome, and play important role in multiple cellular processes. Ongoing researches have showed the variation of DNA methylation among different human populations, and associated with both genetic and environmental factors. China is the most populous country in the world, which is consisted of 56 recognized ethnic groups. Geographical distribution and habitat differences are obvious among some ethnic populations. The most typical example is Tibetans’ adaptation to Qinghai-Tibet Plateau, which is low in oxygen while high in UV radiation. However, until the publication of this work, few study has analyzed the variation of DNA methylation among different ethnic groups in China, not to say the role of epigenetic regulation in Tibetans’ adaptation to high-altitude.

In this work, the authors collected blood samples from 32 participants that came from four Chinese ethnic groups including Chinese Han, Tibetan, Mongolian, and Zhuang. They carried out DSBS, the recently developed high-throughput sequencing technology that could accurately identify both single-nucleotide variants and DNA methylation simultaneously at a single-base resolution by using one dataset. The results of this study suggest that DNA methylation-based epigenetic structure is largely different with the genetic structure that could clearly distinguish the four ethnic groups (Figure 1A). Only a small part of the DNA methylation sites shows ethnic difference and could separate the four groups (Figure 1B). Surprisingly, they found non-ethnic-specific DNA methylation variations correlated more significantly to the global genetic divergence than these ethnic-specific DNA methylation after excluding the influence of within-ethnic and between-ethnic difference (Figure 1C-E), suggesting ethnic-specific DNA methylation variations were determined more by environmental factors other than genetic diversifications. Interestingly, they revealed that DNA methylation differences between Tibetan and other lowland individuals were enriched around high-altitude adaptation related genes including EPAS1 and EGLN1 (Figure 2), that were critical selection signals in Tibetans’ adaptation to highland, suggesting DNA methylation alteration plays an important role in high-altitude adaptation. Besides, they also discussed the accuracy of Nanopore sequencing in human epigenomic study, and explored the reliability and feasibility of this new technology at DNA methylation identification as compared to DSBS. This work not only provide the first batch of epigenetic comparison map for some important Chinese populations and the first evidence of the association of epigenetic changes with Tibetans’ high-altitude adaptation.

 

See the article:

Lin, Z., Lu, Y., Yu, G., Teng, H., Wang, B., Yang, Y., Li, Q., Sun, Z., Xu, S., Wang, W., et al. (2023). Genome-wide DNA methylation landscape of four Chinese populations and epigenetic variation linked to Tibetan high-altitude adaptation. Sci China Life Sci 66, https://doi.org/10.1007/s11427-022-2284-8

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JOURNAL

Science China Life Sciences

DOI

10.1007/s11427-022-2284-8 

Study examines the use of silver diamine fluoride as an early childhood caries management strategy in Indigenous communities

Meeting Announcement

INTERNATIONAL ASSOCIATION FOR DENTAL RESEARCH

Alexandria, VA, USA – A study seeking to understand the perspectives of decision-makers (DMs) working within health fields in First Nations (FNs) communities in Canada regarding the use of Silver Diamine Fluoride (SDF) as an early childhood caries (ECC) management strategy will be presented at the 101st General Session of the IADR, which will be held in conjunction with the 9th Meeting of the Latin American Region and the 12th World Congress on Preventive Dentistry on June 21-24, 2023, in Bogotá, Colombia.

The Interactive Talk presentation, “Decision-Makers’ Perspectives on Silver Diamine Fluoride in Indigenous Communities,” will take place on Wednesday, June 21, 2023, at 3:40 p.m. Colombia Time (UTC-05:00) during the “Fluorides for Caries Control” session.

The study by Fabio Gregorio Arriola-Pacheco of the University of Toronto, Canada carried out six Indigenous Learning Circles (LCs) in five FNs communities in the provinces of Ontario and Manitoba. Information about the status of ECC in these communities and treatment needs were first delivered by researchers as preparational engagement for clinical integration of SDF into the communities’ dental programs. Focus-group-style conversations followed utilizing a semi-structured format, from which audio recordings were later transcribed and analyzed thematically.

Themes which emerged from the LCs included a resistance towards SDF staining, how it compared to other ECC treatment strategies, the need for a prior educational component (to parents and the community at large) as key to SDF’s acceptance, suggestions on implementation strategies, and skepticism – grounded in historical contexts – about the novelty and efficacy of SDF. Some identified themes overlap with recurrent ones in the literature, while others are unique and significant to the DMs’ power position and the cultural context from which the sample was derived.

About IADR

The International Association for Dental Research (IADR) is a nonprofit organization with a mission to drive dental, oral, and craniofacial research for health and well-being worldwide. IADR represents the individual scientists, clinician-scientists, dental professionals, and students based in academic, government, non-profit and private-sector institutions who share our mission. Learn more at www.iadr.org.

An archeological first: A poem by Virgil appears on the remnants of a Roman oil amphora

Peer-Reviewed Publication

UNIVERSITY OF CÓRDOBA

 

IMAGE: REMNANTS OF A ROMAN OIL AMPHORA view more 

CREDIT: UNIVERSITY OF CORDOBA

Measuring just 6 centimeters wide and 8 long, the magnitude and exceptionality of the discovery has left the European archaeological community flabbergasted. It is a fragment of an oil amphora from the Roman region of Betica, manufactured about 1,800 years ago, with a written text on it, found during prospecting carried out in the municipality of Hornachuelos (Córdoba) by members of OLEASTRO, a joint project between the Universities of Cordoba, Seville and Montpellier. Thus far, nothing would have been extraordinary about the find, as countless pieces of pottery from ancient Rome have been found. Monte Testaccio in Rome, an artificial mound comprised of Roman pottery, is an infinite source of information about the Roman olive and wine industry. In fact, at first, the research team was not particularly surprised to receive the fragment from Francisco Adame, a resident of the village of Ochavillo, the first person who noticed that little piece of Rome when walking through Arroyo de Tamujar, an area very close to the village of Villalón (Fuente Palmera).

Neither was the research team astonished by the fact that the amphora featured words, as this is quite common too. In fact, the information printed on amphorae (producers, quantities, control…) has allowed archaeologists to understand the history of agricultural trade during the Empire. Likewise, it was hardly shocking to find a piece of an amphora in an area like theplain of the Guadalquivir River, considered one of the nerve centers of olive oil production and trade throughout the Empire. In the surroundings of Corduba, modern-day Cordoba, a good part of the olive oil consumed by Rome was produced and packaged, as evidenced, for example, by the remnants of amphorae with "Betica" seals preserved on Mount Testaccio.

Thus, the fragment of an amphora with text on it seemed, at first, just another piece, devoid of special interest. Everything changed, however, when the epigraph was deciphered, revealing the following words

S
vais
avoniam
glandemm
arestapoqv
tisaqv
it

Through overlaying, the researchers were able to infer that the text corresponds to the seventh and eighth verses of the first book of The Georgics, a poem by Virgil dedicated to agriculture and life in the countryside, written in 29 BC, which say:

Auoniam[pingui]
glandem m[utauit]
aresta, poq[ulaque]
[inuen]tisAqu[eloia]
[miscu]it [uuis]
C[ambió] la bellota aonia por la espiga [fértil] [y mezcl]ó
el ag[ua] [con la uva descubierta]

Virgil was the most popular poet of his time, and still many centuries later. The Aeneid was taught at schools, and its verses routinely written as a pedagogical exercise for many generations. Thus, it is common to find them on the remains of ceramic construction materials, with many authors deducing that these tablets had educational functions (Roman schoolchildren wrote Virgil on their chalkboards) and funerary ones (Virgil's verses served as an epitaph on many occasions). But, why on an amphora? And why The Georgics, and not The Aeneid? Posing these questions, the researchers on the project realized that the tiny fragment of pottery could be a unique piece, and one of extraordinary value, since Virgil's verses had never been documented on an amphora destined for the oil trade.

The authors' main thesis in the work, published in the Journal of Roman Archaeology (University of Cambridge), in which Dr. Iván González Tobar appears as principal investigator) (PhD, University of Córdoba, currently a Juan de la Cierva researcher at the University of Barcelona, and hired by the University of Montpellier when the piece was found) is that the verses were written on the underside of the amphora without anyone expected to notice them, only as a sign of the knowledge and culture of the person who wrote them, revealing a certain level of literacy in the fertile plain of the Guadalquivir area.

Who wrote it? Here, the authors posit several possibilities: that they were written by a specialized worker of the establishment with a certain degree of literacy, or someone from the nearby villages related to an aristocratic family owning the factory. They are also open to the possibility that a child worker wrote it, as the regular use of young workers at this type of establishment has been previously documented.

In any case, the verses on the amphora from Hornachuelos/Fuente Palmera make it a unique piece posing many more questions in need of answers.

Referencia: González Tobar, I., Soler i Nicolau, A., & Berni Millet, P. (2023). Las Geórgicas de Virgilio in figlinis: A propósito de un grafito ante cocturam sobre un ánfora olearia bética. Journal of Roman Archaeology, 1-22. doi:10.1017/S1047759423000156 

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JOURNAL

Journal of Roman Archaeology

DOI

10.1017/S1047759423000156 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Las Geórgicas de Virgilio in figlinis: a propósito de un grafito ante cocturam sobre un ánfora olearia bética

How tidal range electricity generation could meet future demand and storage problems

Peer-Reviewed Publication

LANCASTER UNIVERSITY

 

IMAGE: THE RESEARCH DEMONSTRATES THE BENEFITS OF TIDAL ENERGY, WHICH DOES NOT SUFFER FROM UNPREDICTABLE INTERMITTENCY AS POWER IS GENERATED BOTH DAY AND NIGHT view more 

CREDIT: LANCASTER UNIVERSITY

Tidal range schemes are financially viable and could lower energy bills say researchers.

Research by Lancaster University’s School of Engineering and the UK Centre for Ecology and Hydrology combined a tidal range power generation model with its cost model to demonstrate the viability of tidal power.

Professor George Aggidis, Head of Energy Engineering at Lancaster University, said: “The obvious question for the UK, with one of the best tidal resources globally, is why haven't we already got a tidal barrage scheme?”

The research published in Energy demonstrates the benefits of tidal energy, which does  not suffer from unpredictable intermittency as power is generated both day and night.

The creation of a tidal barrage could operate for 120 years or more to meet future demand and storage problems.

Professor Aggidis said: “There is an urgent need to kick-start the selection and development of schemes around Britain. Tidal range generation is predictable renewable energy driven by the gravitational pull of the moon and sun. The environmental and economic benefits are huge as barrages can protect coastal areas from flooding and sea level rise. With two-way generation and pumping, the full range of existing tides can be maintained within impoundments to protect and support low-lying intertidal areas such as saltmarshes and mudflats.

Our studies show that with modern technology and operating procedures, estuarine barrages are the only practical way to protect these vital habitats. Coastal lagoons have also been proposed for several locations around Britain’s coast. Schemes will provide jobs in construction and manufacturing for generations to come as well as opportunities for transport, communication, conservation, and recreation. In the long-term they will provide reliable power with reduced costs”.

The UK has the second highest tidal range in the world and offers the UK a level of independence from global prices and in the long-term cheap clean power.

Currently the Tidal Range projects under commercial consideration offer an achievable 10 GW installed capacity, delivering over 20TWh/y, about 5% of UK energy use. Based on the UK relevant resource availability there is the potential to further increase this installed capacity over 4 to 5 times with other tidal range project sites around the UK.

Such developments are essential to assist the UK to reduce its carbon emissions by replacing fossil fuel power stations. The current UK total generating capacity is around 42.8 GW that includes fossil fuels (19.2GW 44.9%), renewables (16.5GW, 38.5%), and low carbon (7.1GW - 16.6%). The La Rance Tidal Range plant in France today generates the cheapest electricity in the EDF fleet -  cheaper than nuclear.

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JOURNAL

Energy

DOI

10.1680/jener.22.00077 

METHOD OF RESEARCH

Computational simulation/modeling

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Tidal range power generation: case studies combining the Lancaster 0-D generation and cost models

 

A new method to keep thickening agents tiny in transport and big in application

Researchers from SANKEN (The Institute of Scientific and Industrial Research), at Osaka University report a dehydration method for cellulose nanofibers that produces a dense powder while maintaining the unique properties of the thickening agent

Peer-Reviewed Publication

OSAKA UNIVERSITY

 

IMAGE: EVAPORATED CNF POWDERS HAVE A SMALL VOLUME AND NO HANDLING ISSUES RELATED TO STATIC ELECTRICITY (UPPER LEFT). THEIR WATER DISPERSIONS ARE COLORLESS AND TRANSPARENT (UPPER RIGHT) AND DISPERSION DROPLETS FORMED BY SPRAYING DO NOT DRIP (LOWER). view more 

CREDIT: 2023 NOGI ET AL., EVAPORATIVE DRY POWDERS DERIVED FROM CELLULOSE NANOFIBER ORGANOGELS TO FULLY RECOVER INHERENT HIGH VISCOSITY AND HIGH TRANSPARENCY OF WATER DISPERSION. MACROMOLECULAR RAPID COMMUNICATIONS

Osaka, Japan – Many commercial products such as food, cosmetics, and inks contain cellulose nanofiber (CNF) as a thickening agent. However, CNFs have some limitations that prevent their more widespread use. Now, researchers from Osaka University have demonstrated a method of dehydrating CNFs to a dense powder without affecting their three key properties. Their findings are published in Macromolecular Rapid Communications.

Video for your easy understanding
https://youtu.be/PAEd36v_SjI 

CNFs are a popular thickening agent because small amounts in water have high transparency, high viscosity, and the viscosity can be controlled. However, the amount of CNF needed in water is very small, so the most efficient way of transporting CNFs is as a dry powder.

Sounds good, but how do we get CNFs into powder form? The water containing the CNFs can be boiled away, but the remaining fibers stick together and redispersing these clumps leads to liquids that are cloudy, unless a lot of energy is used to break up the clumps. If water is removed by freeze drying, the resulting CNF powder is quite fluffy and takes up a lot of space. It is also affected by static electricity, making it difficult to handle.

These are significant drawbacks in industries where efficiency affects profitability. Therefore, the research team from Osaka University devised an improved water-removal method, the first step of which is to form an ‘organogel’, a type of gel consisting partly of organic molecules.

“Our process involves taking a CNF paste in water and dehydrating it by stirring in ethanol,” explains corresponding author Masaya Nogi. “The ethanol is then removed at 30°C, which is a low and cost-effective temperature. After some processing, it can then be redispersed in water simply by stirring.”

The redispersed product was shown to retain the three key properties of CNF thickening agents. Its tunable viscosity was demonstrated by spraying it from a pump spray bottle. It was successfully sprayed from the nozzle, which requires a low viscosity, and the ejected droplets did not run from where they landed on an upright surface, which requires high viscosity behavior. Furthermore, the spray doesn’t generate dripping, which can be a problem with other sprays.

“The large scale of many industrial processes means that all process improvements can have a big impact on the bottom line,” says senior author Masaya Nogi. “Our method of powder creation retains all key properties of CNFs while also enabling effective handling and cheaper transport and storage.”

The ease of use of the organogel-derived CNF powders is expected to make them an attractive prospect for application in many areas, including in the food, cosmetics, and sanitation industries.

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The article, “Evaporative Dry Powders Derived from Cellulose Nanofiber Organogels to Fully Recover Inherent High Viscosity and High Transparency of Water Dispersion,” was published in Macromolecular Rapid Communications at DOI: https://doi.org/10.1002/marc.202300186.

Evaporated CNF powders recover the inherent dispersion properties and are dense, which reduces the transportation and storage costs (upper). Freeze-dried CNF powders recover the inherent dispersion properties, but have a large volume and readily stick to surrounding objects (lower).

CREDIT

2023 Nogi et al., Evaporative Dry Powders Derived From Cellulose Nanofiber Organogels to Fully Recover Inherent High Viscosity and High Transparency of Water Dispersion. Macromolecular Rapid Communications

JOURNAL

Macromolecular Rapid Communications

DOI

10.1002/marc.202300186 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Evaporative Dry Powders Derived From Cellulose Nanofiber Organogels to Fully Recover Inherent High Viscosity and High Transparency of Water Dispersion