The study, published in the Proceedings of the National Academy of Sciences and led by the University of Notre Dame, combined satellite imagery with agricultural surveys as well as household dietary datasets of 160 large-scale land acquisitions across four continents between 2005 and 2015. It is the first comprehensive global analysis of the impact of the land acquisitions of its kind.

“These land deals have been happening for the last two decades on a massive scale,” said Marc Muller, assistant professor in the Department of Civil and Environmental Engineering and Earth Sciences at Notre Dame and lead author of the study. “Our goal was to use empirical data to sort out whether or not large-scale land acquisitions have improved food security by using empirical data. But what we found was that there was either no impact or a negative impact. There was no positive impact.”

Following a global food crisis during the early 2000s, foreign investors purchased more than 220 million acres of land in middle-income and developing countries, according to the study’s estimates, to increase crop production and contribute to the global food supply.

“In many countries throughout the world land is being commodified, so it is becoming easier to buy and sell land. Those, and rising food prices, were drivers for these companies,” Muller said.

There are two competing arguments when it comes to land acquisitions. Proponents view the multinational companies that purchased the land as better positioned to improve production and increase crop yields. But those who oppose argue that the acquisitions encroach on natural resources, lead to displacement of local farm workers and can have a negative impact on local residents — including giving rise to livelihood losses, social instability and/or violence in those regions.

While scientists have analyzed these types of acquisitions using modeling studies, and others have looked at specific situations as a result of the land deals through case studies, Muller said this is the first global analysis of this scale.

Muller and his team analyzed land deals across Latin America, eastern Europe, Africa and Asia. By combining satellite imagery, researchers could see whether crop lands expanded and/or intensified. “We also used data from agriculture surveys to identify what types of crops had been planted in and around those lands prior to the acquisition compared to after, to account for potential transitions from local crops to export-bound crops, and crops that can also be used for biofuel,” such as palm oil and sugar cane, Muller said.

According to the study, trends differed depending on the region — and in some cases the acquisitions had a negative effect on household diets.

In Latin America and eastern Europe — where countries are considered middle-income — investors purchased land in intensified agricultural areas, where crops were already export-bound and local residents already consumed food from global markets. “So, in that sense, these land deals didn’t really change much,” said Muller. “They didn’t increase crop production and they didn’t cause more damage to local food insecurity than what was already taking place. In Africa and Asia, things looked very different.”

The research showed that those land acquisitions increased cropland, cultivating previously uncultivated land, and showed a clear transition from local staple crops such as tapioca to export-bound crops such as wheat and flex crops for potential use as biofuel.

“These crops are interesting for investors because if the price of food is low and the price of energy is high, you can then use the crops for energy,” said Muller. “But these types of crops are not nutrient dense, so it’s not great in terms of food security. As a matter of fact, the data from the household surveys we studied showed a consistent decrease in diet diversity after the deals took place.”

The study is the first in a series the research team will produce based on their analysis. Forthcoming studies will look at the impact of large-scale land acquisitions in relation to water, energy and environment.

Muller is an affiliated member of Notre Dame’s Environmental Change Initiative and a faculty fellow with the Kellogg Institute for International Studies.

Co-authors of the study include Gopal Penny, also at Notre Dame; Meredith T. Niles at the University of Vermont; Vincent Ricciardi at the University of British Columbia; Davide Danilo Chiarelli and Maria Cristina Rulli at the Polytechnic University of Milan; Kyle Frankel Davis at the University of Delaware; Jampel Dell’Angelo at the University of Amsterdam; Paolo D’Odorico and Lorenzo Rosa at the University of California, Berkeley; and Nathan D. Mueller at Colorado State University.

The National Science Foundation, the United States Agency for International Development and the Mava Foundation funded the study.

“Our research shows the highly diverse regional distribution of out-of-hospital sudden death during the COVID-19 pandemic surge and follows the geographic distribution of seroconversion to SARS-CoV-2 in New York City,” explains lead investigator Stavros E. Mountantonakis, MD, FHRS, Northwell Health-Lenox Hill Hospital, Department of Cardiac Electrophysiology, New York, NY, USA. “This finding adds to the previously reported association between out-of-hospital sudden death and COVID-19 presumed deaths and further supports an association between out-of-hospital sudden death and SARS-COV-2 epidemiologic burden.”

The investigators collected results of all antibody tests reported to the New York City Department of Health between March 3 and August 20, 2020 for all New York City zip codes, excluding eight commercial districts. New York City requires mandatory reporting of all tests. Data from March 20 to April 22, 2020, during the height of the pandemic, were obtained from the Fire Department of New York City on the number of patients pronounced dead at the scene from sudden cardiac arrest, the classification the Department uses for out-of-hospital sudden death. For comparison, they collected data for the same period in 2019. Census data were used to examine the possible influence of factors including age, race, access to medical insurance, education, and immigration status.

The investigators found that sudden death during the pandemic varied widely among neighborhoods and there was a moderate positive association between the rate of sudden death in a neighborhood and the percentage of positive antibody tests to SARS-CoV-2. The rate of sudden death in 2019 was also predictive of increased sudden deaths in a neighborhood during the first pandemic surge in New York City.

The investigators note that it is unclear whether this association is causative, or if there are factors that affect the geographic distribution of sudden death and SARS-CoV-2 infection similarly.

Dr. Mountantonakis observes, “The epidemiological data is a direct surrogate of viral burden and indirectly associated with people dying suddenly at home. It remains to be seen whether this is due to cardiac complications related to the virus or poor access to healthcare in neighborhoods that suffered the most during the first wave of the COVID-19 pandemic.”

These findings emphasize the importance of preserving access to healthcare, especially in neighborhoods that suffered disproportionally in the first COVID-19 pandemic wave.

Writing in an accompanying editorial, John R. Giudicessi, MD, PhD, Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, USA, notes that regardless of the ultimate breakdown between direct and indirect effects of COVID-19 on out-of-hospital sudden death incidence, the precipitous rise in New York City and other metropolitan areas is indisputable. “It appears increasingly likely that most areas will have to endure one or more additional surges before the benefits of vaccination efforts take hold,” he comments. “There is hope that maintaining safe access to routine and emergency health services, avoidance of ineffective treatment strategies, and improvements in how COVID-19 patients are monitored and treated in the outpatient setting may help reduce the incidence of out of hospital cardiac arrest and death.”

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Yet archaeology as practiced today bears virtually no resemblance to the tomb raiding portrayed in movies and video games. Indeed, it bears little resemblance to even more scholarly depictions of the discipline in the entertainment sphere.

A paper published today in Nature Ecology and Evolution aims to give pause to an audience that has been largely prepared to take such out-of-touch depictions at face value. It reveals an archaeology practiced by scientists in white lab coats, using multi-million-euro instrumentation and state of the art computers.

It also reveals an archaeology poised to contribute in major ways to addressing such thoroughly modern challenges as biodiversity conservation, food security and climate change.

“Archaeology today is a dramatically different discipline to what it was a century ago,” observes Nicole Boivin, lead author of the study and Director of the Institute’s Department of Archaeology. “While the tomb raiding we see portrayed in movies is over the top, the archaeology of the past was probably closer to this than to present-day archaeology. Much archaeology today is in contrast highly scientific in orientation, and aimed at addressing modern-day issues.”

Examining the research contributions of the field over the past few decades, the authors reach a clear conclusion — archaeology today has a great deal to contribute to addressing the challenges of the modern era.

“Humans in the present era have become one of the great forces shaping nature,” emphasizes Alison Crowther, coauthor and researcher at both the University of Queensland and the MPI Science of Human History. “When we say we have entered a new, human-dominated geological era, the Anthropocene, we acknowledge that role.”

How can archaeology, a discipline focused on the past, hope to address the challenges we face in the Anthropocene?

“It is clear that the past offers a vast repertoire of cultural knowledge that we cannot ignore,” highlights Professor Boivin.

The two researchers show the many ways that data about the past can serve the future. By analysing what worked and didn’t work in the past — effectively offering long-term experiments in human society — archaeologists gain insight into the factors that support sustainability and resilience, and the factors that work against them. They also highlight ancient solutions to modern problems.

“We show how researchers have improved the modern world by drawing upon information about the ways people in the past enriched soils, prevented destructive fires, created greener cities and transported water without fossil fuels,” notes Dr. Crowther.

People also continue to use, and adapt, ancient technologies and infrastructure, including terrace and irrigation systems that are in some cases centuries or even millennia old.

But the researchers are keen to highlight the continued importance of technological and social solutions to climate change and the other challenges of the Anthropocene.

“It’s not about glorifying the past, or vilifying progress,” emphasizes Professor Boivin. “Instead, it’s about bringing together the best of the past, present and future to steer a responsible and constructive course for humanity.”

In a study published today in Nature Climate Change, the interdisciplinary team of environmental engineers, Earth system scientists and data science experts stressed that not all parts of the tropics will be affected equally. For instance, the rain belt will move north in parts of the Eastern Hemisphere but will move south in areas in the Western Hemisphere.

According to the study, a northward shift of the tropical rain belt over the eastern Africa and the Indian Ocean will result in future increases of drought stress in southeastern Africa and Madagascar, in addition to intensified flooding in southern India. A southward creeping of the rain belt over the eastern Pacific Ocean and Atlantic Ocean will cause greater drought stress in Central America.

“Our work shows that climate change will cause the position of Earth’s tropical rain belt to move in opposite directions in two longitudinal sectors that cover almost two thirds of the globe, a process that will have cascading effects on water availability and food production around the world,” said lead author Antonios Mamalakis, who recently received a Ph.D. in civil & environmental engineering in the Henry Samueli School of Engineering at UCI and is currently a postdoctoral fellow in the Department of Atmospheric Science at Colorado State University.

The team made the assessment by examining computer simulations from 27 state-of-the-art climate models and measuring the tropical rain belt’s response to a future scenario in which greenhouse gas emissions continue to rise through the end of the current century.

Mamalakis said the sweeping shift detected in his work was disguised in previous modelling studies that provided a global average of the influence of climate change on the tropical rain belt. Only by isolating the response in the Eastern and Western Hemisphere zones was his team able to highlight the drastic alterations to come over future decades.

Co-author James Randerson, UCI’s Ralph J. & Carol M. Cicerone Chair in Earth System Science, explained that climate change causes the atmosphere to heat up by different amounts over Asia and the North Atlantic Ocean.

“In Asia, projected reductions in aerosol emissions, glacier melting in the Himalayas and loss of snow cover in northern areas brought on by climate change will cause the atmosphere to heat up faster than in other regions,” he said. “We know that the rain belt shifts toward this heating, and that its northward movement in the Eastern Hemisphere is consistent with these expected impacts of climate change.”

He added that the weakening of the Gulf Stream current and deep-water formation in the North Atlantic is likely to have the opposite effect, causing a southward shift in the tropical rain belt across the Western Hemisphere.

“The complexity of the Earth system is daunting, with dependencies and feedback loops across many processes and scales,” said corresponding author Efi Foufoula-Georgiou, UCI Distinguished Professor of Civil & Environmental Engineering and the Henry Samueli Endowed Chair in Engineering. “This study combines the engineering approach of system’s thinking with data analytics and climate science to reveal subtle and previously unrecognized manifestations of global warming on regional precipitation dynamics and extremes.”

Foufoula-Georgiou said that a next step is to translate those changes to impacts on the ground, in terms of flooding, droughts, infrastructure and ecosystem change to guide adaptation, policy and management.

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Up to 20% of the world’s population suffers from the irritable bowel syndrome (IBS), which causes stomach pain or severe discomfort after eating. This affects their quality of life. Gluten-free and other diets can provide some relief, but why this works is a mystery, since the patients are not allergic to the foods in question, nor do they have known conditions such as coeliac disease.

“Very often these patients are not taken seriously by physicians, and the lack of an allergic response is used as an argument that this is all in the mind, and that they don’t have a problem with their gut physiology,” says Professor Guy Boeckxstaens, a gastroenterologist at KU Leuven and lead author of the new research. “With these new insights, we provide further evidence that we are dealing with a real disease.”

Histamine

His team’s laboratory and clinical studies reveal a mechanism that connects certain foods with activation of the cells that release histamine (called mast cells), and subsequent pain and discomfort. Earlier work by Professor Boeckxstaens and his colleagues showed that blocking histamine, an important component of the immune system, improves the condition of people with IBS.

In a healthy intestine, the immune system does not react to foods, so the first step was to find out what might cause this tolerance to break down. Since people with IBS often report that their symptoms began after a gastrointestinal infection, such as food poisoning, the researchers started with the idea that an infection while a particular food is present in the gut might sensitise the immune system to that food.

They infected mice with a stomach bug, and at the same time fed them ovalbumin, a protein found in egg white that is commonly used in experiments as a model food antigen. An antigen is any molecule that provokes an immune response. Once the infection cleared, the mice were given ovalbumin again, to see if their immune systems had become sensitised to it. The results were affirmative: the ovalbumin on its own provoked mast cell activation, histamine release, and digestive intolerance with increased abdominal pain. This was not the case in mice that had not been infected with the bug and received ovalbumin.

A spectrum of food-related immune diseases

The researchers were then able to unpick the series of events in the immune response that connected the ingestion of ovalbumin to activation of the mast cells. Significantly, this immune response only occurred in the part of the intestine infected by the disruptive bacteria. It did not produce more general symptoms of a food allergy.

Professor Boeckxstaens speculates that this points to a spectrum of food-related immune diseases. “At one end of the spectrum, the immune response to a food antigen is very local, as in IBS. At the other end of the spectrum is food allergy, comprising a generalised condition of severe mast cell activation, with an impact on breathing, blood pressure, and so on.”

The researchers then went on to see if people with IBS reacted in the same way. When food antigens associated with IBS (gluten, wheat, soy and cow milk) were injected into the intestine wall of 12 IBS patients, they produced localised immune reactions similar to that seen in the mice. No reaction was seen in healthy volunteers.

The relatively small number of people involved means this finding needs further confirmation, but it appears significant when considered alongside the earlier clinical trial showing improvement during treatment of IBS patients with anti-histaminics. “This is further proof that the mechanism we have unravelled has clinical relevance,” Professor Boeckxstaens says.

A larger clinical trial of the antihistamine treatment is currently under way. “But knowing the mechanism that leads to mast cell activation is crucial, and will lead to novel therapies for these patients,” he goes on. “Mast cells release many more compounds and mediators than just histamine, so if you can block the activation of these cells, I believe you will have a much more efficient therapy.”

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The study, published today (Wednesday) in the European Heart Journal [1], found that, compared to drinking no alcohol at all, just one alcoholic drink a day was linked to a 16% increased risk of atrial fibrillation over an average (median) follow-up time of nearly 14 years. This means that while four teetotallers in 100 might develop atrial fibrillation over the period of the study, five per 100 might develop the condition if they consumed alcohol starting with slightly more than an alcoholic drink a week and more than 75% of them consumed up to one drink a day [2]. The researchers categorised one alcoholic drink as containing 12 g of ethanol, which is the equivalent of a small (120 ml) glass of wine, a small beer (330 ml) or 40 ml of spirits.

It is well known that people who drink a lot of alcohol regularly are at increased risk of developing heart failure, and heart failure can increase the incidence of atrial fibrillation. Several studies have shown a slightly higher risk of heart problems for people who never drink alcohol; they often show that this risk reduces for people who drink a modest amount, and then rises sharply the more alcohol is consumed, creating a ‘J’ shape on graphs. Until now, it has not been clear whether this was also the case for atrial fibrillation.

However, in the current study led by Professor Renate Schnabel, a consultant cardiologist at the University Heart and Vascular Center, Hamburg-Eppendorf (Germany), researchers found that although low doses of alcohol were associated with a reduced risk of heart failure compared to teetotallers, a similar ‘J’ shape reduction in risk was not seen for atrial fibrillation. This suggests that the increased risk of atrial fibrillation among people drinking small amounts of alcohol was not triggered by heart failure.

Prof. Schnabel said: “To our knowledge, this is the largest study on alcohol consumption and long-term incidence of atrial fibrillation in the community. Previous studies have not had enough power to examine this question, although they have been able to show a relationship between alcohol intake and other heart and blood vessel problems, such as heart attack and heart failure. In our study, we can now demonstrate that even very low regular alcohol consumption may increase the risk of atrial fibrillation.

“These findings are important as the regular consumption of alcohol, the ‘one glass of wine a day’ to protect the heart, as is often recommended for instance in the lay press, should probably no longer be suggested without balancing risks and possible benefits for all heart and blood vessel diseases, including atrial fibrillation.”

The researchers analysed information on 107,845 people taking part in five community-based studies in Sweden, Norway, Finland, Denmark and Italy. The participants underwent medical examinations at the time they joined the studies between 1982 and 2010 and provided information on their medical histories, lifestyles (including alcohol and tobacco consumption), employment and education levels. A total of 100,092 participants did not have atrial fibrillation when they enrolled and their median age was nearly 48 years (range 24-97 years).

During the median follow-up period of nearly 14 years, 5,854 people developed atrial fibrillation. The associations between alcohol consumption and the risk of atrial fibrillation were similar for all types of alcoholic drinks and for men and women.

In addition to the 16% increased risk of atrial fibrillation compared to teetotallers seen in people who consumed only one alcoholic drink a day, the researchers found that the risk increased with increasing alcohol intake; up to two drinks a day was associated with a 28% increased risk and this went up to 47% for those who consumed more than four.

The exact mechanisms by which modest amounts of alcohol could trigger atrial fibrillation are not known. Studies have shown that heavy drinking over a short period of time can trigger ‘holiday heart syndrome’ in some people, and in some atrial fibrillation patients, small amounts of alcohol can trigger arrhythmia episodes.

Limitations of the study include the fact that study participants reported the type and quantity of alcohol they drank and this could lead to under-reporting; the information available did not enable the researchers to look at the effects of binge drinking; some episodes of atrial fibrillation can be asymptomatic and so may not have been reported; only adults across Europe were included in the analyses and so it may not be possible for the results to be generalised to other populations; as the study was observational, it can show only an association between alcohol intake and atrial fibrillation and not that alcohol causes atrial fibrillation.

In an accompanying editorial [3], Jorge A. Wong and David Conen from the Population Health Research Institute at McMaster University, Hamilton, Canada, write that the research “makes an important contribution to our understanding of the relationship between alcohol intake and incident AF, in particular at the lower spectrum of alcohol consumption. A significant relationship between alcohol and AF was identified, and even small quantities of alcohol were associated with an increased, albeit small, risk of incident AF.

“Together with a recent randomized trial showing that a reduction in alcohol intake led to a reduction in AF recurrence, these data suggest that lowering alcohol consumption may be important for both prevention and management of AF. Importantly, any reduction in low-to-moderate alcohol consumption to potentially prevent AF needs to be balanced with the potentially beneficial association low amounts of alcohol may have with respect to other cardiovascular outcomes . . . The net clinical benefit of consuming low amounts of alcohol requires further study, ideally in adequately powered randomized trials. Until then, each individual has to make its own best educated decision as to whether consuming up to one alcoholic drink per day is worthwhile and safe.”

Notes:

[1] “Alcohol consumption, cardiac biomarkers and risk of atrial fibrillation and adverse outcomes,” by Dora Csengeri et al. European Heart Journal. doi:10.1093/eurheartj/ehaa953

[2] Data on absolute risk are not given in the research paper. The absolute risk was calculated using further information from the researchers and the University of Cambridge Winton Centre for Risk and Evidence Communication RealRisk web tool: https://url.wintoncentre.uk/p6lcb

[3] “Alcohol consumption, atrial fibrillation, and cardiovascular disease: finding the right balance,” by Jorge A. Wong and David Conen. European Heart Journal. doi:10.1093/eurheartj/ehaa955