This is a disheartening statistic, especially given the projected need for a 33% increase in the number of STEM-degree holders nationwide to support the industries of the future. Also disheartening: Those that leave their majors are disproportionately first-generation and underrepresented students, which is contributing to a lack of diversity in both industry and at advanced levels of research.

It doesn’t have to be this way, say Mike Wilton and Eduardo Gonzalez-Niño, lecturers in the UC Santa Barbara Department of Molecular, Cellular, and Developmental Biology. In a paper published in the journal CBE-Life Sciences Education, the pair and their colleagues demonstrate that an active learning approach — the use of tactics such as in-class iClickers, small group discussions and peer-reviewed writing assignments — early in the biological sciences improves grades in the short-term and increases student retention in biology over the long-term.

“All students that are admitted here to UC Santa Barbara are capable of pursuing the biology major, otherwise the university would not have admitted them,” said Wilton, who, with the rest of his team, has been running the BioMentors program for undergraduate biology majors since 2015.

Unfortunately, the researchers said, that sense of belonging is often lost in the mix as students — many of whom are the first in their family to attend university — navigate large class sizes, a fast-paced quarter system and a multitude of hurdles they did not expect along the way.

“I also faced that conundrum,” Gonzalez-Niño said, thinking of his early years as a biology major. “Sometimes the background that these students have is not ideal — they came from high schools that didn’t prepare them for the rigor that you face in college.” In addition to feeling out of place in a completely new environment and not knowing who to turn to for help, he said, these students often perform badly, leading them to lose confidence in their abilities and to reconsider their major.

At UCSB, roughly 1,100 new undergraduates are admitted into the biology major each year; however, about 600 have tended to leave the major after their first two years of study. Wilton and Gonzalez-Niño wanted to see if they could keep undergrads from prematurely leaving by involving them in a more participatory style of learning.

In their three-year research project, cohorts of students participated in an alternative and parallel — but no less rigorous — introductory biology course that ran concurrently to the traditional lecture course. In addition to active learning strategies, the intervention course replaces a weekly lecture with a tutorial that focuses on historically difficult course concepts. These discussion-based tutorials are led by Wilton and Gonzalez-Niño with the assistance of upper-division biology students, called BioMentors, who model approaches and strategies for success.

“The thing that we try to instill the most is that we’re all in this together,” Wilton said.

Following three years’ worth of introductory biology students in both versions of the course, the researchers found significant benefits to those in the intervention section. For example, those in the intervention course outperformed their peers in the traditional lecture course by about 12% on common exam questions, and participation in the active learning program resulted in higher final course grades overall.

The students who participated in the active learning program also reported a “significantly higher perception of student belonging when compared with peers in the traditional section,” according to the study. Students attributed this to the “higher perceptions of faculty support” and classroom environment — i.e., how easy it is to share ideas and ask questions in lecture.

“The students in the active learning course were comfortable approaching us,” Gonzalez-Niño said. “They can tell that we’re on their side.”

Taken together, the improved performance and the greater sense of belonging, the researchers said, increased the likelihood that students would remain in the biology major. In fact, students in the intervention course were 10% more likely than their peers in the traditional lecture course to participate in the subsequent introductory biology course offered the following quarter.

A biology degree is broad and diverse enough to enable individuals to work in various fields that will need these STEM graduates. According to the researchers, there is a growing demand for biologists in the biomedical fields, environmental sciences, agriculture and nutrition, and in research that not only broadens our knowledge, but also can translate into innovation.

“A huge area of demand currently that is only projected to grow is healthcare,” Wilton noted. “If we can teach these students to navigate through their first gateway biology courses and help them pursue career in healthcare, that will be a productive future for a lot of students who are first-generation.”

In addition, Gonzalez-Niño said, assisting underrepresented students in overcoming hurdles to learning biology will boost diversity in the field.

“When you have people with the same background all think about the same questions, often there’s a limited number of answers that you can come up with,” he said. “But when you have a diverse group of people thinking about the same issues, then the answers to those issues become more creative and diverse.”

China is ahead of most low- and middle-income countries in its energy transition: hundreds of millions of rural homes started using clean fuels such as electricity and gas in recent decades. Despite this, many Chinese homes continue using their traditional coal and wood-burning stoves — a trend that is common in many countries.

Traditional stoves linked to premature deaths and climate change

Air pollution from traditional stoves contributed to approximately 2.8 million premature deaths in 2017 and is a major contributor to regional climate change. Efforts made by governments, NGOs, and researchers to incentivize households to switch entirely to clean fuel stoves and give up their traditional stoves — even in highly controlled randomized trials — have largely failed.

“Families have used their traditional stoves for generations. People know what foods taste best with those stoves and how to best use them so that all energy needs are met,” said Jill Baumgartner, an Associate Professor in McGill’s Department of Epidemiology, Biostatistics and Occupational Health and the senior author on the study by an international team of researchers. “Clean fuel stoves do not always meet all of the energy uses provided by traditional stoves, and may also pose additional costs. The desire to continue using traditional stoves is also seen in the U.S. and Canada, where many homes still use wood fireplaces for space heating despite being well-equipped to only use gas and electric heaters.”

Giving up is hard to do

The researchers gathered data from over 700 homes in three provinces in China (Beijing, Shanxi and Guangxi) using a photo-based questionnaire, which allowed participants to point to each type of stove that they had ever owned. They then asked questions about the frequency and timing of use, as well as what fuel types they used with the household stoves.

“We were surprised by the number of stoves current used in different homes, sometimes up to 13 different cooking devices and 7 different heating stoves,” said Ellison Carter, the first author on the paper who is an Assistant Professor in the Department of Civil and Environmental Engineering at Colorado State University. “We were also surprised to find that most homes that had first started using clean fuels well over a decade ago were still using their solid fuel stoves, again highlighting the enormous challenge of achieving exclusive use of clean fuel stoves.”

The researchers found that the factors associated with adoption of clean fuels were different from those associated with the suspension of traditional coal and wood burning stoves. The common traits among those who stopped using traditional stoves were that they tended to be younger, more educated, and had poorer self-reported health. Those who adopted clean technology tended either to be younger or retired, lived in smaller households, and had a higher income.

Looking at uptake of clean fuels at a global level

This study focused only on China, which is home to over 500 million solid fuel stove users. But an important question for the researchers is how generalizable these results from China are to other countries with different levels of economic development. They were recently awarded funding from the U.S. NIH to develop a framework on the household and community factors that can facilitate suspension of solid fuel stoves. For this work, they obtained a number of nationally-representative datasets on energy use from India, Cambodia, and number of countries in Sub-Saharan Africa to empirically assess this same question in other settings.

“We have good evidence from many countries on the policies and program that can promote the uptake of clean fuel stoves,” said Baumgartner. “We now need to better understand the individual or combinations of policies and programs that can accelerate the suspension of solid fuel stoves, particularly for the poorest and most vulnerable.”

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Living cells are difficult to grow in the laboratory, so researchers sometimes work with synthetic cells, but these have had research limitations because they lack real cell characteristics.

“One of the challenges of cell research is it’s sometimes very hard to run controlled experiments on a?cell’s motility, especially due to surface enzyme activity,” said Darrell Velegol, distinguished professor of chemical engineering. “The research team developed a simple way to make an artificial cell that doesn’t do everything a regular cell does, like reproduce, have genetic mutations or anything like that, but it actively moves. That’s important because how cells move is poorly understood, especially how enzymes’ activity play into cell movement.”

The team’s protocells are used to investigate how the activity of natural enzymes like ATPase can propel the active movement of the protocells. The biochemical process of ATPase enzyme involves conversion of ATP (adenosine triphosphate) into the product ADP (adenosine diphosphate). ATP is a complex organic chemical that provides energy for living cells and ADP is an organic compound that plays an important role in how cells release and store energy.

“Attempts at similar experiments in the past decade had the enzymes incorporated inside of micron-sized sacks called polymeric vesicles, or tethered onto the surface of hard particles,” said Subhadip Ghosh, postdoctoral researcher in chemistry. “But these attempts didn’t have significant biological resemblance like our protocells.”

In the research team’s experiments, the protocells have actual artificial membranes composed of a naturally occurring lipid called phosphatidylcholine. The ATPase enzymes were incorporated directly into the membrane.

“Our results basically give other researchers the first steps toward making artificial cells with enzymatic activity,” Ghosh said.

One unexpected result from the study, which was made available online in August 2019 ahead of final publication on September 11, 2019 in an issue of Nano Letters, happened during diffusion experiments which were performed at a single molecular regime. As expected, the movement of the protocells was low for low concentrations of ATP.

“Quite surprisingly, the movement of the protocells dropped significantly at high concentration of ATP,” said Ayusman Sen, the Verne M. Willaman Professor of Chemistry at Penn State.

According to the researchers, this was as counterintuitive as pressing an automobile’s gas pedal and having the vehicle slow down. After performing comprehensive control experiments, the researchers concluded that when ADP concentration is high, it may bind to the ATPase and suppress the substrate ATP activity, causing reduced motility.

Having the ability to fabricate the enzymatically active protocells opens new opportunities. Armed with these mimics of motile living cells, the researchers aim to reveal the fundamental mechanisms governing active membrane dynamics and cellular movement.?Given the current limited understanding of how cells move, including how enzyme action plays into cell movement, the research team members believe their work can have significant implications for future medical research.

“A key challenge is to estimate the mechanical forces that drive the protocell movement, and to discover changes in the enzyme structure during that process,” said Farzad Mohajerani, research assistant in chemical engineering. “Knowing that structure-function relationship for the movement of the protocells will enable their design for potential in vivo applications like medical sensing and lab analysis.”

Along with Ghosh, Mohajerani, Velegol and Sen, other Penn State researchers who participated in the study included Peter Butler, associate dean for education and graduate professional programs in the College of Engineering and professor of biomedical engineering, and Seoyoung Son, postdoctoral researcher in biomedical engineering.

The National Science Foundation’s Center for Chemical Innovation supported this research.

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Materials provided by Penn State. Original written by Jamie Oberdick. Note: Content may be edited for style and length.

Though it sounds like science fiction, it’s a serious suggestion to combat climate change: ten million wind-powered pumps, distributed throughout the Arctic, are intended to promote the formation of sea ice in the winter. They would continually pump seawater onto the surface of the ice, where it would freeze. The now-thicker ice could then survive the summertime melting longer and therefore reflect sunlight longer where otherwise the darker ocean would readily take up the sun’s warming rays. This could not only slow the loss of Arctic sea ice, but also mitigate remote impacts, perhaps even the warming in lower latitudes. The idea, first proposed by US researchers as ‘Arctic ice management’ in the journal Earth’s Future in 2017, was recently put to the test in a coupled climate model by two experts from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI). What they found: from a purely physical standpoint, the near-total loss of summertime sea ice, which will likely come by mid-century in the ‘business-as-usual’ scenario, could indeed be pushed back to the end of the century. However, this grace period would not entail any significant cooling for the climate in Europe or around the globe.

“We wanted to know whether this manipulation of the Arctic sea ice could work in purely physical terms, and what effects it would have on the climate,” says Lorenzo Zampieri, an environmental physicist and doctoral candidate from the AWI’s sea-ice prediction research group. Accordingly, he modified the AWI climate model so that the physical effect produced — the constant pumping of water onto the sea ice’s surface throughout the winter — could be simulated. As Helge Goessling, head of the research group, explains: “Normally the growth of the ice is limited by the fact that, as it becomes thicker, the ice increasingly insulates the ocean from the winter cold; for this reason, typically you won’t find an overall thickness of more than a few metres. But the pumps do away with this limiting effect, because new layers are added to the ice from above.” Initial simulations based on pumps churning seawater onto the ice throughout the Arctic show: year after year, the ice would gain between one and two metres in thickness. According to the climate model, the global warming produced by CO₂ wouldn’t put an end to this growth until the end of the century. And what about the effects on the climate? The summertime warming of the Arctic would in fact be lessened by several degrees Celsius, as projected in the original publication. However, pumping the comparatively warm (-1.8 °C) water would also alter the thermal flow in winter, resulting in a substantial warming of the Arctic in winter. This thermal energy would also be transported to the middle latitudes and stored in the ocean there.

In the next step, the researchers conducted more realistic simulations in which the pumps were only deployed where the ice was less than two metres thick. “Two-metre-thick ice already has the best chances of surviving the summertime melting, and by limiting the distribution of pumps in this way, the unnecessary and considerable wintertime warming can also be avoided,” says Lorenzo Zampieri. In this scenario, the undesirable additional warming of the middle latitudes could in fact be avoided, but the scheme would still do little to mitigate climate change. Though the warming of the Arctic in summer would be reduced by roughly one degree Celsius, and the loss of the sea ice could be delayed by roughly 60 years, the increased reflection of sunlight wouldn’t be sufficient to slow climate change outside the Arctic.

“Given the unchecked progression of climate change to date, geo-engineering can’t be dismissed as mere nonsense by the climate research community,” claims Helge Goessling. Instead, these ideas need to be subjected to scientific scrutiny. Arctic ‘ice management’, both authors agree, is interesting in its own right, but can’t meaningfully mitigate global climate change; as such, it should remain science fiction.

In a recent study, scientists around Agnes Dellinger from the Department of Botany and Biodiversity Research from the University of Vienna investigated flowers of 30 species of a tropical plant group (Merianieae) from the Andes. “Each of these plant species has adapted to pollination by either bees, birds, bats or rodents,” says Dellinger. Using High-Resolution X-ray computed tomography, the research team produced 3D-models of these flowers and used geometric-morphometric methods to analyse differences in flower shape among species with different pollinators.

The researchers could show that flower shapes have evolved in adaptation to the distinct pollinators, but that flower shape evolution was not homogeneous across the flower. In particular, the showy sterile organs of flowers (petals) adapted to the different pollinators more quickly than the rest of the flower: the reproductive organs have evolved more slowly. “This study is among the first to analyse the entire 3-dimensional flower shape, and it will be exciting to see whether similar evolutionary floral modularity exists in other plant groups,” concludes Dellinger.

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Journal Reference:

1. Agnes S. Dellinger, Silvia Artuso, Susanne Pamperl, Fabián A. Michelangeli, Darin S. Penneys, Diana M. Fernández-Fernández, Marcela Alvear, Frank Almeda, W. Scott Armbruster, Yannick Staeder, Jürg Schönenberger. Modularity increases rate of floral evolution and adaptive success for functionally specialized pollination systems. Communications Biology, 2019; 2 (1) DOI: 10.1038/s42003-019-0697-7

But according to new research out of UC Santa Barbara, the rains that come once the storm has weakened may actually be more intense than when the storm is at its strongest.

“The highest intensities of rainfall occur after the hurricanes have weakened to tropical storms, not when they first make landfall as major hurricanes,” said lead author Danielle Touma, a postdoctoral scholar at the university’s Bren School of Environmental Science & Management. The study appears in the journal Geophysical Research Letters.

The finding has counterintuitive implications. “If we’re thinking about risks, we know that major hurricanes can drive storm surges, there’s strong winds and so on. But this paper is also saying hurricanes are still dangerous even after they’ve weakened to tropical storms,” said coauthor Samantha Stevenson, an assistant professor at Bren.

Around the time Hurricane Harvey hit Houston in 2017, Touma was developing a new method for studying areas and intensities of rainfall around tropical cyclones — which include hurricanes and tropical storms — based on weather station data. Many previous studies have used satellite and radar data, but these records are limited to the late 20th and early 21st centuries. In contrast, records from weather stations begin in 1900. Using the measurements from the stations, Touma could calculate the extent of land that experienced rain from a given weather system, as well as how much rain fell.

These issues were in sharp focus during the 2017 hurricane season, especially as flooding in Southern Texas racked up roughly $130 billion in damages, according to the National Oceanic and Atmospheric Administration.

Analyzing decades of records, Touma discovered that the accompanying rainfall tended to be more severe after a hurricane had abated to the category of a tropical storm. In that sense, the cyclones were more dangerous after they had subsided, in spite of their slower wind speeds.

“You might think hurricanes are most dangerous when they’re strongest, because that’s when the winds are whipping around the fastest,” Stevenson said, “but this paper actually finds that the risk due to extreme rainfall is largest after the hurricane has weakened a bit.”

Tropical cyclones tend to slow down once they hit land because they are cut off from their energy source, the ocean. There’s no longer warm water evaporating below them to drive the convection that fuels the system. As a result, the cyclone becomes disorganized and spins at lower speeds, causing it to spread out. “Now it’s kind of parked in one spot, and it can just dump a lot of rain on a particular location,” Stevenson explained.

Naturally, this effect is most pronounced for cyclones that started as major hurricanes. A smaller cyclone would follow the same pattern — hit land, slow down and spread out — but it wouldn’t contain the sheer volume of water to cause the same degree of damage.

Scientists predict that the intensity of tropical cyclone rainfall will increase as global temperatures rise. In fact, the team has already begun to see this trend in their historical data.

“Since our analysis used longer records than previous studies, we were better able to detect long-term trends,” Stevenson explained. “What this paper adds to the conversation is which types of storms we have to pay more attention to in disaster preparedness plans.”

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Materials provided by University of California – Santa Barbara. Original written by Harrison Tasoff. Note: Content may be edited for style and length.