Model more accurately maps the impact of frost on corn crops

Tool uses remote sensing to reduce uncertainties regarding agricultural losses, contributing to public policy.

Fundação de Amparo à Pesquisa do Estado de São Paulo

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Brazilian researchers have developed a methodology that uses remote sensing to map the impact of frost on corn crops. This reduces exposure to climate risks and uncertainty regarding agricultural losses.

The model allows users to customize a set of variables, making it useful for other crops in different agricultural contexts. Thus, it has the potential to provide more accurate estimates during harvests and contribute to the development of public policies that support production chains and insurance systems.

Global grain production, particularly of rice, corn, wheat, and soybeans, is concentrated in just five countries: China, the United States, India, Brazil, and Argentina. Fluctuations in harvests in these countries can affect both prices and the global supply. These crops have also been affected by climate change, experiencing severe droughts, extreme rainfall, and more frequent frosts. This issue has been brought to negotiation rounds such as COP30, held in Belém.

In the study, the scientists mapped over 700,000 hectares of corn planted for the second harvest in the western mesoregion of Paraná state (in the areas around Toledo and Cascavel) to identify damage caused by severe frosts recorded between May and June of 2021.

The scientists integrated optical remote sensing data (MultiSpectral Instrument sensor with medium spatial resolution aboard the Sentinel-2 mission satellites) with machine learning techniques (Random Forest algorithm). They achieved 96% accuracy in mapping corn crops and revealed that 70% were damaged by frost during that time. They were able to map the affected areas using the method they called GEEadas.

The results were published in the December issue of the journal Remote Sensing Applications: Society and Environment.

“In 2021, we had a drought that disrupted soybean planting in Paraná and, as a result, delayed corn planting. Then, in June, came the news of the frost. That region normally has high rainfall, which benefits crops. But we see that the climate in recent years hasn’t been normal,” says Marcos Adami, a researcher from the Earth Observation and Geoinformatics Division (DIOTG) of the National Institute for Space Research (INPE) and one of the authors of the article. “A crop failure there greatly affects the lives of the people, most of whom depend on agribusiness. Developing this study is a way to provide tools that give answers and contribute to the planning of measures that help maintain this important activity.”

Adami has been working with Professor Michel Eustáquio Dantas Chaves, from the Faculty of Sciences and Engineering at São Paulo State University (UNESP) in Tupã, for several years on remote sensing research focused on practical applications in agriculture.

“Producers still face a number of climatic uncertainties during the harvest, especially when there are extreme events, such as frost, which have social, economic, and environmental impacts. In such cases, it’s necessary to identify how much of the crop has been affected in order to inform the farmer, the banks that grant credit, or institutional bodies. This method provides accuracy, indicating the affected area and reducing uncertainties,” says Chaves, first author of the article, which received support from FAPESP. 

Importance of the sector

In its October 2025 estimate, the Brazilian Institute of Geography and Statistics (IBGE) reported that the national harvest of cereals, legumes, and oilseeds reached 345.6 million tons, which is 18% higher than in 2024 and a record high in the historical series. The three main products are rice, corn, and soybeans, which together account for 93% of the estimated production and 88% of the harvested area.

Paraná is the second-largest grain producer in Brazil, behind only Mato Grosso. The production estimate for corn in 2025 was 141.6 million tons, which is also a record.

The 2019/2020 harvest produced around 103 million tons, according to the study. This was double the amount produced in the previous decade, with three-quarters of the supply coming from the second harvest. In that harvest, corn is grown after soybeans and is harvested between June and July. This increase was made possible by changes in management practices, such as adopting new fertilizers and cultivating short-cycle corn.

Generally, the second corn crop is riskier than the first due to lower water availability and exposure to climatic events, including frost. Despite having frost risk warning systems, Brazil lacks accurate methodologies to assess damage.

To validate the method, the researchers compared corn mapping areas and frost damage estimates with official data provided by the State Department of Agriculture and Supply. They also used information from insurance companies. Farmers typically file insurance claims to recover losses caused by adverse events. For each claim, an agricultural specialist visits the farm and analyzes the damage.

“In the field, agricultural technicians have spatial limitations, which are natural to the activity. Seeing from above with remote sensing images allows us to complement the technicians’ work,” Chaves explained to Agência FAPESP.

Adami says he is working with the National Supply Company (CONAB) in the states of Rio Grande do Sul, Paraná, and São Paulo to develop methodologies and collect data to obtain more accurate crop yield figures.

About São Paulo Research Foundation (FAPESP)
The São Paulo Research Foundation (FAPESP) is a public institution with the mission of supporting scientific research in all fields of knowledge by awarding scholarships, fellowships and grants to investigators linked with higher education and research institutions in the State of São Paulo, Brazil. FAPESP is aware that the very best research can only be done by working with the best researchers internationally. Therefore, it has established partnerships with funding agencies, higher education, private companies, and research organizations in other countries known for the quality of their research and has been encouraging scientists funded by its grants to further develop their international collaboration. You can learn more about FAPESP at www.fapesp.br/en and visit FAPESP news agency at www.agencia.fapesp.br/en to keep updated with the latest scientific breakthroughs FAPESP helps achieve through its many programs, awards and research centers. You may also subscribe to FAPESP news agency at http://agencia.fapesp.br/subscribe.

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Journal

Remote Sensing of Environment

DOI

10.1016/j.rsase.2025.101799 

Article Title

GEEadas: GEE-based automatic detection of adverse-frost stress

 

How did humans develop sharp vision? Lab-grown retinas show likely answer

Organoid technology pioneered at Johns Hopkins could spur new therapies for vision loss

Johns Hopkins University

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image: 

Robert J. Johnston Jr., associate professor of biology at Johns Hopkins, holds a petri dish enclosing a retinal organoid grown in his lab. 

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Credit: Will Kirk/Johns Hopkins University

Humans develop sharp vision during early fetal development thanks to an interplay between a vitamin A derivative and thyroid hormones in the retina, Johns Hopkins University scientists have found.  

The findings could upend decades of conventional understanding of how the eye grows light-sensing cells and could inform new research into treatments for macular degeneration, glaucoma, and other age-related vision disorders. 

Details of the study, which used lab-grown retinal tissue, are published today in Proceedings of the National Academy of Sciences.

“This is a key step toward understanding the inner workings of the center of the retina, a critical part of the eye and the first to fail in people with macular degeneration,” said Robert J. Johnston Jr., an associate professor of biology at Johns Hopkins who led the research. “By better understanding this region and developing organoids that mimic its function, we hope to one day grow and transplant these tissues to restore vision.” 

In recent years, the team pioneered a new method to study eye development using organoids, small tissue clusters grown from fetal cells. By monitoring these lab-grown retinas over several months, the researchers discovered the cellular mechanisms that shape the foveola—a central retinal region responsible for sharp vision. 

Their research focused on light-sensitive cells that enable daytime vision. These cells develop into blue, green, or red cone cells that have sensitivity to different types of light. Although the foveola comprises only a small fraction of the retina, it accounts for about 50% of human visual perception. The foveola contains red and green cones but not blue cones, which are distributed more broadly across the rest of the retina. 

Humans are unique in having these three types of cones for color vision, allowing people to see a wide spectrum of colors that are relatively rare in other animals. How eyes grow with this distribution of cells has puzzled scientists for decades. Mice, fish, and other organisms commonly used for biological research do not have this patterning of cells, which makes the photoreceptor cells difficult to study, Johnston said. 

The Johns Hopkins team concluded the distribution of cones in the foveola results from a coordinated process of cell fate specification and conversion during early development. Initially, a sparse number of blue cones are present in the foveola at weeks 10 through 12. But, by week 14, they transform into red and green cones. The patterning occurs by way of two processes, the new study shows. First, a molecule derived from vitamin A called retinoic acid is broken down to limit the creation of blue cones. Second, thyroid hormones encourage blue cones to convert into red and green cones. 

“First, retinoic acid helps set the pattern. Then, thyroid hormone plays a role in converting the leftover cells,” Johnston said. “That’s very important because if you have those blue cones in there, you don’t see as well.”  

The findings offer a different perspective to the prevailing theory that blue cones migrate to other parts of the retina during development. Instead, the data suggest that these cells convert to achieve optimal cone distribution in the foveola. 

“The main model in the field from about 30 years ago was that somehow the few blue cones you get in that region just move out of the way, that these cells decide what they’re going to be, and they remain this type of cell forever,” Johnston said. “We can’t really rule that out yet, but our data supports a different model. These cells actually convert over time, which is really surprising.” 

The insights could pave the way for new therapies for vision loss. Johnston and his team are working to refine their organoid models to better replicate human retina function. These advancements could lead to improved photoreceptors and potential cell-based treatments for eye diseases such as macular degeneration, which have no cure, said author Katarzyna Hussey, a former doctoral student who graduated from Johnston’s lab.  

“The goal with using this organoid tech is to eventually make an almost made-to-order population of photoreceptors. A big avenue of potential is cell replacement therapy to introduce healthy cells that can reintegrate into the eye and potentially restore that lost vision,” said Hussey, who is now a molecular and cell biologist at cell therapy company CiRC Biosciences in Chicago. “These are very long-term experiments, and of course we’d need to do optimizations for safety and efficacy studies prior to moving into the clinic. But it’s a viable journey.” 

 

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Journal

Proceedings of the National Academy of Sciences

DOI

10.1073/pnas.2510799123 

Article Title

A cell fate specification and transition mechanism for human foveolar cone subtype patterning

Article Publication Date

13-Feb-2026

COI Statement

Johnston holds a patent for this work and recently co-founded a company called Agnos Therapeutics to explore its potential.

 

White paper connecting rural broadband gaps to organizational wellness and workforce stability published by the University of Phoenix College of Doctoral Studies

Research by Dr. Stella Smith draws on Career Institute® study to examine how digital access challenges affect rural workers and organizations

University of Phoenix

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University of Phoenix College of Doctoral Studies today announced the publication of a new research white paper, “The Rural Digital Divide and Organizational Wellness,” by Stella Smith, Ed.D. The paper analyzes how persistent disparities in digital access affect employee well-being, career development and organizational resilience in rural communities, and explores opportunities presented by the integration of AI technologies into rural economies.

Smith’s research connects with broader workforce trends identified in the University of Phoenix Career Institute® G.R.O.W. Generating Rural Opportunities in the Workforce™ report, a national study conducted in partnership with the Center on Rural Innovation (CORI). That study surveyed workers in rural and nonrural America to assess barriers related to technological infrastructure, career advancement and access to modern workforce opportunities — including disparities in broadband quality and digital tools that are critical to organizational performance and career mobility.

Smith’s white paper shows how these digital limitations contribute to stress, limit remote work opportunities, restrict access to modern upskilling and reduce organizational agility. The research underscores that the digital divide is not only a technology gap but a workforce and wellness issue with measurable impacts on productivity and economic participation.

“When individuals lack reliable connectivity and accessible digital tools, it creates cascading effects for organizational health, from employee engagement and retention to access to training and long-term career resilience,” said Smith. “Closing the rural digital divide supports workforce stability and stronger organizational wellness.”

White paper highlights:

• Evidence linking rural broadband limitations to reduced access to remote work and professional education;
• Analysis of how digital access barriers affect organizational wellness indicators, including staff engagement and career progression;
• Opportunities presented by AI integration and digital skill-building; and
• Strategic recommendations for employers, community partners and policymakers to bridge gaps in digital access and support healthier work environments.

The white paper builds on findings from the G.R.O.W. report, which revealed significant outcomes such as rural workers reporting poorer quality internet and technology — and identifying these gaps as obstacles to career advancement and economic opportunity.

The full white paper is available on the University of Phoenix on the Career Institute® webpage and the Research Hub.

About the author

Smith is the associate university research chair for CEITR and an associate faculty member in the College of Doctoral Studies at the University of Phoenix whose work focuses on organizational wellness, access to opportunity and the implications of technological infrastructure on workforce outcomes. Her research integrates applied data with strategic insights to help leaders implement initiatives that strengthen employee well-being and organizational performance. Smith earned her doctorate in educational administration from The University of Texas at Austin.

About University of Phoenix 

University of Phoenix innovates to help working adults enhance their careers and develop skills in a rapidly changing world. Flexible schedules, relevant courses, interactive learning, skills-mapped curriculum for our bachelor’s and master’s degree programs and a Career Services for Life® commitment help students more effectively pursue career and personal aspirations while balancing their busy lives. For more information, visit phoenix.edu.

About the College of Doctoral Studies

University of Phoenix’s College of Doctoral Studies focuses on today’s challenging business and organizational needs, from addressing critical social issues to developing solutions to accelerate community building and industry growth. The College’s research program is built around the Scholar, Practitioner, Leader Model which puts students in the center of the Doctoral Education Ecosystem® with experts, resources and tools to help prepare them to be a leader in their organization, industry and community. Through this program, students and researchers work with organizations to conduct research that can be applied in the workplace in real time.

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Article Publication Date

6-Feb-2026

 

At AAAS, professor Krystal Tsosie argues the future of science must be Indigenous-led

Arizona State University

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Krystal Tsosie, an expert in Indigenous genomics, bioethics, and data governance, will deliver a talk titled The Future of Science Is Indigenous at the American Association for the Advancement of Science Annual Meeting.

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Credit: ASU

Krystal Tsosie, an expert in Indigenous genomics, bioethics, and data governance, will deliver a talk titled The Future of Science Is Indigenous at the American Association for the Advancement of Science Annual Meeting. One of the world’s largest cross-disciplinary science gatherings, the AAAS meeting is a key venue for debate about how emerging technologies should be governed. Tsosie’s presentation examines how Indigenous science offers frameworks for equity, accountability, and stewardship as genomics, artificial intelligence, and precision health reshape research and society.

 

Her talk comes at a moment of rapid expansion in genomics, artificial intelligence, and high-energy data infrastructure, raising urgent questions about data governance, environmental responsibility, and scientific accountability. Tsosie argues that genomics is not only about generating genetic sequences, but about governance, consent, and long-term stewardship of both DNA and associated digital data. Decisions made now about data use and accountability, she emphasizes, will shape health outcomes far into the future.

 

Drawing on Indigenous science as a framework rather than a perspective, Tsosie highlights governance models that have guided decision-making for generations. These models, she argues, are increasingly vital for building trustworthy health and data systems that are accountable to communities and responsive to future needs. Centering Indigenous science offers both a correction to extractive power dynamics of the past and a blueprint for more just and sustainable scientific futures.

 

Tsosie grounds her talk in the legacy of uranium mining on Arizona tribal nations, including her own Navajo community. She discusses how harmful health outcomes linked to environmental exposure were historically interpreted primarily through genetic explanations, often sidelining environmental pathways and questions of accountability. This history, she notes, reflects failures of data governance, scientific responsibility and justice, with impacts that persist across generations.

 

She connects these lessons to current debates over renewed genetics research in Indigenous populations, expansion of data centers in water-scarce regions such as Arizona, and the growing energy demands of artificial intelligence systems. Her talk asks whether emerging science infrastructure will repeat extractive patterns or adopt more accountable and reciprocal models.

 

“Science has always claimed to study the future. Indigenous peoples have always planned for it,” Tsosie says. “We are at a turning point in genomics, AI and precision health. The question is not what we can build, but who science is built for.”

 

The AAAS Annual Meeting brings together scientists, policymakers and the public, making it a critical venue for conversations about how science infrastructure is designed and who benefits from it. Tsosie emphasizes that Indigenous science is not new. What is new is whether institutions are willing to recognize Indigenous ways of knowing and include them in advancing science responsibly.

 

Tsosie is an assistant professor in the School of Life Sciences at Arizona State University and an internationally recognized leader in ethical genomic data practice. Her work advances equity and accountability in genomics research involving Indigenous communities across health, biomedicine, conservation biology and ancient DNA, at the intersection of genomics, Indigenous data sovereignty, artificial intelligence governance and environmental justice."