The findings, published in Science Advances, show that wildfire smoke can attach to home surfaces like carpet, drapes or counters — extending the exposure for those inside and potentially causing health problems even after an initial cleaning activity by air purifiers. However, Professor Delphine Farmer said the research also shows that simple surface cleaning — like vacuuming, dusting or mopping — can reduce exposure and limit risk.

The research illustrates the hidden and persistent health threats many in the Western U.S. are facing given the increase in wildfires over the last decade, she said.

“This research shows that events like the Marshall Fire in Colorado, the wildfires in Canada and the recent fires in Hawaii present serious exposure potential — not just when they occur but well after,” said Farmer, who is based in the Department of Chemistry at CSU. “This paper is a key initial step towards providing actionable and practical information on how to protect yourself and clean your home.”

To better understand how smoke enters and then stays in buildings, researchers burned pine wood chips in a net zero energy residential testing facility operated by the National Institute of Standards and Technology (NIST) in Maryland. That facility is frequently used to study how different systems impact the ways energy, water and air move through a single-family house. The detailed instrumentation available for that work was perfectly suited to this research, said Dustin Poppendieck, an environmental researcher at NIST who helped coordinate the project.

“The NIST Net Zero House allowed the researchers to track the movement and transformation of chemicals in the air and onto surfaces in real time using instruments in ways that don’t interfere with the behavior of the smoke,” said Poppendieck.

Those smoke injection sessions occurred regularly over several days, and Farmer said the total amount applied was comparable or slightly under the particulate levels seen during the Canadian wildfires. The team then took careful measurements of air quality levels and surface conditions after opening exterior doors and windows, cleaning and use of the home’s built-in air cleaning systems.

The CSU team was particularly interested in the gas-phase of compounds developing from the smoke, while other teams from the University of California San Diego, CU Boulder and the University of North Carolina Chapple Hill explored different phases and interactions across the home. The team then compared findings between states to confirm what was actually happening in the home after the burn.

Farmer said findings from this interdisciplinary research approach could also be applicable to other large air pollution events like the train derailment in East Palestine, Ohio, where the same principles of compounds sticking to surfaces are likely to occur.

Because there has not been a lot of similar indoor air research, the team leaned on previous findings from others around the effects of cigarette smoke to inform their approach. Farmer said burning nicotine causes specific compounds with well-known health concerns and that the comparison to their project findings was informative.

“Nicotine reacts on surfaces to create a particularly nasty set of compounds called nitrosamines, which is where the real concern from thirdhand smoke that is left behind comes from,” she said. “Whereas with wildfire smoke, we found there was a huge diversity of organic compounds that stick to surfaces, which then slowly bleed off.”

The amount, persistence and variety of compounds from the wildfire smoke in each case could potentially change the recommended approaches for cleaning the indoor spaces. Farmer said that is an area of research the team hopes to explore in the future. For now, she said the team was able to show that the amount of smoke left on surfaces was proportional to the surface area that was cleaned. That means simple cleaning and specifically addressing large but little noticed spaces that may trap harmful compounds such as cabinets and HVAC systems could be beneficial right away.

“As we continue this research, we would like to know just how effective different cleaning approaches are and when residents should move from relatively simple steps like using commercial cleaning supplies for mopping to more drastic steps like replacing the drywall altogether,” Farmer said.

Farmer’s team was also recently funded by the W.M. Keck Foundation to research how smog may enter and remain in the home in much the same way as wildfire smoke. That work will be particularly important in Colorado where ground-level ozone pollution is a continuing issue.

“In the future I want to explore how the economics of making a more energy efficient building play into these questions and help people understand the risks and potential solutions available to them,” Farmer said. “CSU is well positioned to lead this kind of interdisciplinary work and address the practical implications because of the land-grant service mission that drives our university.”

Reinecke, who joined the JGU Institute of Geography in May 2023, has made a major contribution to the new WMO report — in collaboration with Dr. Hannes Müller Schmied of Goethe University Frankfurt and the Senckenberg Leibniz Biodiversity and Climate Research Center Frankfurt (SBiK-F) as well as the Global Runoff Database Center (GRDC) in Koblenz. Together they supplied simulation data based on hydrological modeling, participated in the development of the corresponding methodology, and provided scientific validation of the report’s key statements. With the WMO acting as coordinating body, the report results from the expertise provided by 11 international modeling groups. The State of Global Water Resources 2022 report was published on October 12, 2023.

Scientifically validated findings on the global water situation

The first State of Global Water Resources Report for 2021 was presented in late November 2022 at the WMO headquarters in Geneva. The report is to appear annually and provide an overview of the status of the Earth’s water resources. The effects of climatic fluctuations and changes can often also be seen by what happens to our water: Heatwaves coupled with droughts can make wildfires more likely and these can then spread more rapidly due to the lack of soil moisture, to give only one example. “The WMO report is thus also designed to provide politicians and the industry with knowledge so as to identify regions that are at risk of experiencing water emergencies or are already in crisis,” added Reinecke.

Among the data shown in the 2022 report is information on the discharge rate of rivers, the levels of groundwater, soil moisture, and evaporation. However, generation of the data basis itself is problematic in that there are currently insufficient global statistics available. “Thus, we need to undertake simulation modeling,” explained Reinecke, a specialist in modeling techniques. There is a particular lack of data on the situation regarding groundwater. Even Germany cannot provide complete figures as to the related circumstances. However, there is no doubt that the dry conditions in 2022 had considerable impact in Germany, too. Just as in the case of the River Po in Italy, the water levels of the Rhine fell dramatically over longer periods, with the associated consequences for river traffic. France suffered from insufficient precipitation, resulting in difficulties when it came to providing the cooling required by nuclear power plants. South America experienced severe drought conditions while, despite increasing precipitation, groundwater levels in the important Murray-Darling Basin in Australia continued to drop below normal.

New Earth System Modeling group at Mainz University

Robert Reinecke was appointed to a junior professorship at JGU’s Institute of Geography in May 2023. Here he will establish an Earth System Modeling group. After studying computer science at TU Darmstadt, being awarded a doctorate by Goethe University Frankfurt, and undertaking research in California, he was employed at the International Center for Water Resources and Global Change (ICWRGC). He subsequently undertook research as a postdoc at the Institute of Environmental Science and Geography of the University of Potsdam. His research focuses on global groundwater in the context of global hydrological modeling. He also investigates surface water/groundwater interaction, the human impact on groundwater resources, and the impact of climate change on the hydrological cycle.

Antibody-drug conjugates (ADCs) have become an eminent cancer treatment because of their ability to precisely target tumors with potent efficacy. HER2-ADC therapies have been effective in treating breast, lung, bladder, and stomach cancers. Although they are usually well-tolerated, multiple doses of the drugs can result in severe side effects, including low blood counts, liver damage, and lung damage. Strategies that reduce toxic side effects caused by ADCs and predictive biomarkers of ADC toxicity are currently an unmet clinical need.

“In this study, we sought to determine whether a single dose of HER2-ADCs could be administered in combination with lovastatin (which temporarily elevates cell-surface HER2) to achieve therapeutic efficacy similar to that of a multiple dose regime,” said Patricia Pereira, PhD, assistant professor at the Mallinckrodt Institute of Radiology at the Washington University School of Medicine in St. Louis, Missouri. “We also used HER2-targeted immuno-PET to monitor changes in HER2 expression after ADC therapy.”

Researchers injected mice with cultured gastric cancer cells and patient-derived gastric cancer cells. When tumors grew sufficiently, the mice were divided into groups and received various treatment schedules (no treatment, multiple doses of ADC, multiple doses of ADC with lovastatin, single dose of ADC, or single dose of ADC with lovastatin). Immuno-PET was used to investigate the dosing regimen and the efficacy of the treatment schedules.

A single dose of ADC therapy combined with lovastatin was found to reduce tumor volume at rates similar to those resulting from multiple doses of ADC in a preclinical setting. The study results showed that immuno-PET can noninvasively monitor HER2 tumor levels after treatment with HER2-targeted ADC therapies.

“This preclinical work is significant because it has the potential to improve therapy for patients with HER2-positive cancers,” noted Pereira. “It not only simplifies treatment by exploring single-dose schedules of antibody-drug conjugates but can also reduce side effects by minimizing the number of doses required. Additionally, it personalizes therapy using molecular imaging, enhancing treatment efficacy.”

She continued, “The findings suggest a future where molecular imaging techniques play a critical role in guiding drug development and cancer treatment decisions, particularly as various ADCs are being tested and approved for cancer treatment. Currently, there is no perfect way to select tumors or monitor their response to ADCs. This research indicates that molecular imaging can bridge this gap by providing real-time insights into therapy response.”

This study was made available online in June 2023.

Phytoplankton in the ocean are central to the global carbon cycle as they perform photosynthesis, capturing and transporting carbon (C) to the deep ocean. The growth of phytoplankton relies not only on carbon but also on nitrogen (N) and phosphorus (P), which are crucial for their cellular functioning. Phytoplankton stoichiometry defines the relative proportions of different elements such as C, N, and P in these organisms. Key connections exist between phytoplankton stoichiometry and climate through interdependencies between the oceanic carbon pump, nutrient cycling, food web dynamics, and responses to climate-related factors like atmospheric carbon dioxide (CO₂) concentration and temperature.

In the 1930s, the American oceanographer Alfred C. Redfield made an important discovery: he found that the concentrations of the elements C, N, and P in the marine phytoplankton roughly follow a fixed ratio of approximately 106:16:1 — the ratio now named after him, the Redfield ratio. Surprisingly, Redfield’s research also revealed that in the seawater samples he collected, the concentration of nitrate, a primary nitrogen nutrient source, was, on average, 16 times higher than the concentration of phosphate, a primary phosphorus nutrient source. The nitrogen-to-phosphorus (N:P) ratios in both phytoplankton and seawater are remarkably similar, indicating a strong connection between the particulate (phytoplankton) and dissolved (seawater) nutrient pools.

The question of whether the N:P ratio of the dissolved pool controls the ratio in particulate material, or vice versa, has long puzzled the marine science community. “It’s a chicken-and-egg question,” says Dr Chia-Te Chien, a researcher in the Biogeochemical Modelling Research Unit at the GEOMAR Helmholtz Centre for Ocean Research in Kiel, who is investigating the role of variable stoichiometry of phytoplankton in the marine biogeochemistry. Together with his colleagues, he has now carried out a modelling study that examines the relationship between the ratios of nitrogen and phosphorus in dissolved inorganic and particulate organic matter in seawater. The study, now published in the journal Science Advances, emphasizes the importance of variable C:N:P ratios of phytoplankton for regulating dissolved oceanic nutrient ratios on a global scale and highlights marine oxygen levels as a critical regulator in the Earth system.

To investigate these relationships, the authors used a computer model of algal physiology coupled to an Earth system model, wherein phytoplankton dynamically optimize their C:N:P ratios in response to varying environmental conditions. In the computer model, they could alter the characteristics of phytoplankton and observe how this changed the nitrogen and phosphorus ratios in the water.

They carried out an ensemble of 400 simulations, which differ in the minimal nitrogen and phosphorus contents required by algae to stay alive. The model results reveal intricate feedback mechanisms involving changes in the nitrogen and phosphorus content of phytoplankton, oceanic oxygen levels, N₂ fixation by nitrogen-fixing phytoplankton, and denitrification. These model results challenge the commonly hypothesized strong link between phytoplankton and seawater nutrient ratios. Rather than attempting to uncover the reasons behind the resemblance in the currently observed ratios between phytoplankton and seawater, the results highlight that these ratios are not inherently similar. In other words, the similarity, as it is observed these days, is a specific state, and this state may be subject to change, at least on a time scale that is not covered by the many decades of ocean in situ observations.

Additionally, the analysis highlights the potentially substantial influence of phytoplankton subsistence nitrogen and phosphorus quotas on atmospheric CO₂ levels on geological time scales. Traditionally, stoichiometric variations of the phytoplankton and within the marine ecosystem were considered to have a relatively minor impact on marine biogeochemistry and, consequently, atmospheric CO₂ levels. This view could now be questioned, because this study points to the potential importance of a physiological detail for climate conditions on our planet.

The authors explain the significance of the findings: “Our results demonstrate that the concentration of atmospheric CO₂ as well as the ocean and air temperature are remarkably sensitive to variations in elemental stoichiometry induced by changes in phytoplankton physiology.” Understanding these connections could help scientists make more accurate predictions about how our planet’s ecosystems and climate will evolve in the future.

Lots of Americans — about one-third of us — are in the same situation and habitually get only five to six hours of sleep instead of the recommended seven to eight hours.

But even a mild chronic sleep deficit may heighten the risk of developing heart disease later in life: Surveys of thousands of people have found that people who report mild but chronic sleep deficits have more heart disease later in life than people who get adequate sleep.

A new Columbia study of women now shows what’s happening in the body during chronic mild sleep deprivation.

After just six weeks of shortened sleep, the study found, the cells that line our blood vessels are flooded by damaging oxidants. And unlike well-rested cells, sleep-restricted cells fail to activate antioxidant responses to clear the destructive molecules.

The result: cells that are inflamed and dysfunctional, an early step in the development of cardiovascular disease.

“This is some of the first direct evidence to show that mild chronic sleep deficits cause heart disease,” says study leader Sanja Jelic, MD, director of the Center for Sleep Medicine at Columbia and professor of medicine in the Division of Pulmonary, Allergy, and Critical Care Medicine at Columbia University Vagelos College of Physicians and Surgeons.

“Until now we’ve only seen associations between sleep and heart health in epidemiological studies, but these studies could be tainted by many confounders that cannot be identified and adjusted for. Only randomized controlled studies can determine if this connection is real and what changes in the body caused by short sleep could increase heart disease.”

Previous studies did not examine chronic sleep deficits

Studies of human sleep have examined the physiological effects of a few nights of profound sleep deprivation.

“But that’s not how people behave night after night. Most people get up around the same time each day but tend to push back their bedtime one to two hours,” Jelic says. “We wanted to mimic that behavior, which is the most common sleep pattern we see in adults.”

The researchers screened nearly 1,000 women in Washington Heights for the study, enrolling 35 healthy women who normally sleep seven to eight hours each night who could complete the 12-week study.

For six weeks the women slept according to their usual routine; for the other six weeks they went to bed 1.5 hours later than usual. Each participant’s sleep was verified with wrist-worn sleep trackers.

Bottom line: Just go to sleep

“Many problems could be solved if people sleep at least seven to eight hours per night,” Jelic says.

“People who are young and healthy need to know that if they keep getting less sleep than that, they’re aggravating their cardiovascular risk.”

Next steps

Recent epidemiological studies suggest that inconsistent bedtimes may raise the risk of heart disease. Jelic’s team is designing a study to see if bedtime variability impacts vascular cells in the same way as chronic, but regular, short sleep.