Culture

Researchers digging at the University of North Carolina at Charlotte's ongoing archaeological excavation on Mount Zion in Jerusalem have announced a second significant discovery from the 2019 season - clear evidence of the Babylonian conquest of the city from 587/586 BCE.

The discovery is of a deposit including layers of ash, arrowheads dating from the period, as well as Iron Age potsherds, lamps and a significant piece of period jewelry - a gold and silver tassel or earring. There are also signs of a significant Iron Age structure in the associated area, but the building, beneath layers from later periods, has yet to be excavated.

The Mount Zion Archaeological Project, co-directed by UNC Charlotte professor of history Shimon Gibson, Rafi Lewis, a senior lecturer at Ashkelon Academic College and a fellow of Haifa University, and James Tabor, UNC Charlotte professor of religious studies, has been in operation for over a decade and has made numerous significant finds relating to the ancient city's many historical periods, including the announcement made in July, 2019 on evidence concerning the sack of the city during the First Crusade. The current find is one of the oldest and perhaps the most prominent in its historical significance, as the Babylonian conquest of Jerusalem is a major moment in Jewish history.

The team believes that the newly-found deposit can be dated to the specific event of the conquest because of the unique mix of artifacts and materials found -- pottery and lamps, side-by-side with evidence of the Babylonian siege represented by burnt wood and ashes, and a number of Scythian-type bronze and iron arrowheads which are typical of that period.

Because of the site's location, various alternative explanations for the artifacts can be eliminated, the researchers argue. "We know where the ancient fortification line ran," noted Gibson, "so we know we are within the city. We know that this is not some dumping area, but the south-western neighborhood of the Iron Age city - during the 8th century BCE the urban area extended from the "City of David" area to the south-east and as far as the Western Hill where we are digging."

The ash deposits, similarly, are not conclusive evidence of the Babylonian attack in themselves, but are much more so in the context of other materials.

"For archaeologists, an ashen layer can mean a number of different things," Gibson said. "It could be ashy deposits removed from ovens; or it could be localized burning of garbage. However, in this case, the combination of an ashy layer full of artifacts, mixed with arrowheads, and a very special ornament indicates some kind of devastation and destruction. Nobody abandons golden jewelry and nobody has arrowheads in their domestic refuse."

"The arrowheads are known as 'Scythian arrowheads' and have been found at other archaeological conflict sites from the 7th and 6th centuries BCE. They are known at sites outside of Israel as well. They were fairly commonplace in this period and are known to be used by the Babylonian warriors. Together, this evidence points to the historical conquest of the city by Babylon because the only major destruction we have in Jerusalem for this period is the conquest of 587/586 BCE," he said.

The clay artifacts also help date the discovery. The lamps, Gibson notes, are the typical high-based pinched lamps of the period.

"It's the kind of jumble that you would expect to find in a ruined household following a raid or battle," Gibson said. "Household objects, lamps, broken bits from pottery which had been overturned and shattered... and arrowheads and a piece of jewelry which might have been lost and buried in the destruction."

"Frankly, jewelry is a rare find at conflict sites, because this is exactly the sort of thing that attackers will loot and later melt down."

"I like to think that we are excavating inside one of the 'Great Man's houses' mentioned in the second book of Kings 25:9," Gibson speculated. "This spot would have been at an ideal location, situated as it is close to the western summit of the city with a good view overlooking Solomon's Temple and Mount Moriah to the north-east. We have high expectations of finding much more of the Iron Age city in future seasons of work. "

The building that is apparently part of the layer remains unexcavated. "One might ask why haven't we excavated the whole building?" Gibson said. "The reason is that we are slowly taking the site down, level by level, period by period, and at the end of this last digging season two meters of domestic structures from later Byzantine and Roman periods have still to be dug above the Iron Age level below. We plan to get down to it in the 2020 season."

The unexpected and rare piece of jewelry found is apparently a tassel or earring, with a bell-shaped gold upper part. Clasped beneath is a silver part made in the shape of a cluster of grapes. Gibson noted that this discovery of jewelry "is a unique find and it is a clear indication of the wealth of the inhabitants of the city at the time of the siege." The only other discovery of jewelry in Jerusalem from this period was made many years ago in 1979 in an Iron Age tomb at Ketef Hinnom outside the city.

The researchers say that finding evidence of a critical historical event is what makes the discovery particularly exciting. Lewis, another co-director of the project, explained that "It is very exciting to be able to excavate the material signature of any given historical event, and even more so regarding an important historical event such as the Babylonian siege of Jerusalem."

By all accounts the Babylonian conquest of the city by the Neo-Babylonian king Nebuchadnezzar was ferocious and resulted in a great loss of life, with the razing of the city and the burning of houses, and the plundering and dismantling of King Solomon's Temple to God. The local ruler of the Kingdom of Judah, King Zedekiah, made an attempt to flee the city with his retinue, but was eventually caught and taken captive to Babylon.

The Hebrew Bible relates the famine and suffering that the inhabitants of Jerusalem suffered during the lengthy Babylonian siege of the city: "So the city was besieged unto the eleventh year of King Zedekiah. On the ninth day of the [fourth] month the famine was sore in the city, so that there was no bread for the people of the land. Then a breach was made in the city, and all the men of war [fled] by night by the way of the gate between the two walls.... And he [Nebuzaradan, the Babylonian captain of the guard] burnt the house of the Lord, and the King's house; and all the houses of Jerusalem, even every great man's house, burnt he with fire." (2 Kings 25: 1-9).

The Babylonian siege of Jerusalem lasted for quite a while even though many of the inhabitants wanted to give up. "King Zedekiah simply was not willing to pay tribute to Nebuchadnezzar and the direct result of this was the destruction of the city and the Temple", said Gibson.

Every year religious Jews in Jerusalem and across the world pray and fast in remembrance of the destruction of the Jewish Temple to God in Jerusalem, first by the Babylonians in 587/586 BCE, resulting in the exile of the inhabitants of the city to Babylon, and yet again in 70 CE at the hands of the Roman legions led by Titus. To remember the devastating destruction of the Temple, Jews gather in synagogues around the world and at the Western Wall plaza in Jerusalem, to pray and mourn on Tisha B' Av (the ninth day in the Hebrew month of Av) according to the Jewish calendar, which falls this year on August 11th.

The Mount Zion archaeological project is directed by Shimon Gibson and James Tabor from the College of Liberal and Arts Studies at the University of North Carolina at Charlotte, in conjunction with Rafi Lewis of Ashkelon Academic College and Haifa University, and with sponsorship from Aron Levy, John Hoffmann, Cherylee and Ron Vanderham, and Patty and David Tyler and others, and facilitated by Sheila Bishop for The Foundation for Biblical Archaeology.

The dig is also staffed by a host of volunteers, including UNC Charlotte students. The project has been a favorite summer activity of for many of UNC Charlotte's Levine Scholars Program, the university's highly selective national program for undergraduate scholars.

"Participating in the Mount Zion dig has been an amazing opportunity for the Levine Scholars," said Diane Zablotsky, director of UNC Charlotte's Levine Scholars Program. "Although they are from different backgrounds and study in different majors, they shared a unique experience that left them with a deep appreciation of archaeology, the history of Jerusalem, and broadened worldview."

The site is within the "Sovev Homot" park administered by the Israel Nature and Parks Authority. Other substantial remains of the multi-period ancient city were uncovered during the 2019 season, including vaulted basements from the time of Herod the Great, a Byzantine street which was the south-westerly continuation of the main city street known as the Cardo Maximus, and a sunken defense ditch that ran in front of the fortifications which greeted the Crusader's when they attacked Jerusalem in 1099 and hindered their assault on the city.

The complex architectural sequence of superimposed structures dating back 3000 years or so is being carefully mapped by a team of recorders and draftsmen headed by Steve Patterson. The University of North Carolina at Charlotte has been conducting archaeological excavations in Jerusalem since 2006 and much vital historical and archaeological information has been steadily extracted from the digging operations.

CHICAGO -- Having productive conversations about climate change isn't only challenging when dealing with skeptics, it can also be difficult for environmentalists, according to two studies presented at the annual convention of the American Psychological Association.

The first of the studies found that reinforcing belief and trust in science may be a strategy to help shift the views of climate change skeptics and make them more open to the facts being presented by the other side.

"Within the United States, bipartisan progress on climate change has essentially come to a standstill because many conservatives doubt the findings of climate science and many liberals cannot fathom that any rational human can doubt the scientific consensus on the issue," said Carly D. Robinson, MEd, of Harvard University, who presented the research. "These opposing perspectives do not create a starting point for productive conversations to help our country address climate change. Our goal was to find an intervention that might change the current situation."

Though previous research has shown that social pressure to disbelieve in climate change stems from the political right and that conservatives' trust in science has eroded, Robinson and her colleagues theorized that most people would find at least some branches of science credible. Leveraging those beliefs could lead climate skeptics to shift their views, they said.

"When people are faced with two or more opposing beliefs, ideas and values, it tends to create discomfort, which can lead people to becoming more open-minded about a particular issue," said Christine Vriesema, PhD, of the University of California, Santa Barbara and a co-author of the study.

The researchers surveyed nearly 700 participants from the U.S. Half were given surveys about their belief in science (e.g., "How credible is the medical data that germs are a primary cause of disease?" and "How certain are you that physicists' theory of gravity accurately explains why objects fall when dropped?") and their belief in climate science (e.g., "How credible is the climate science data that ocean temperatures are rising?" and "How certain are you that global warming explains many of the new weather patterns we are seeing today?"). The other half was only surveyed about their belief in climate science. All participants reported if they considered themselves politically liberal, moderate or conservative.

"As we predicted in our pre-registration, conservatives reported a greater belief in climate science if they were asked questions first about their belief in other areas of science," said Robinson. "For climate skeptics, it likely became awkward to report on our survey that they believed in science while at the same time, denying the findings of climate science. That dissonance led many to adjust their beliefs to show greater support for the existence of climate change."

The findings showed that beliefs in climate science are malleable and not fixed, said Robinson.

"We were pleasantly surprised that a brief, two-minute survey changed skeptics' views on climate change," said Robinson. "It is exciting to know that in real-world settings, we might be able to have more productive climate conversations by starting from a place of common belief."

The second study showed that igniting a sense of resilience and perseverance can increase action and engagement around climate change for people who work in aquariums, national parks and zoos.

"Many educators working at these institutions reported wanting to talk about climate change and visitors reported wanting to hear about it, yet many educators still felt uncomfortable bringing the topic into their conversations because they were worried about being able to communicate effectively," said Nathaniel Geiger, PhD, of Indiana University who presented the research.

The study included 203 science educators from zoos, aquariums and national parks who were part of a yearlong communication training program from the National Network of Ocean and Climate Change Interpretation designed to build participants' confidence in talking about climate change. The training consisted of study groups, group assignments, readings, discussions and weekend retreats. During the last six months of the program, participants worked to integrate what they had learned into their jobs.

Survey data were collected one month before and one month after the training program and again six to nine months later.

Geiger and his colleagues examined two components of hopeful thinking to see which one might lead to the success of the training program: agency (e.g., enthusiasm, a sense of determination) and pathways (e.g., resilience and perseverance strategies) and how those influenced participants' reports of engagement about climate change.

Participants rated their "agency thinking" (e.g., "I energetically do all I can do to discuss climate change" and "I anticipate that efforts to discuss climate change will be pretty successful") and their "pathways thinking" (e.g., "I can think of many ways to discuss climate change") in each survey. The science educators also reported the frequency with which they discussed climate change with the general public and visitors to their institutions, ranging from never to daily.

Geiger and his team found that pathways thinking was more successful at inspiring conversations about climate change than agency.

"Our findings suggested that portions of the training that taught how to persevere and be resilient in the face of difficult climate change conversations may have been the most effective at promoting discussion," Geiger said.

The training program also increased the frequency with which the science educators spoke about climate change with visitors, from less than once per month prior to the training to more than two or three times per month afterward, he said.

"We found it uplifting that the training program showed such a robust effect at promoting these difficult discussions," said Geiger. "We believe that climate change advocates and educators will find this work helpful toward meeting their goal of crafting more effective training programs to boost climate change engagement."

COLUMBUS, Ohio - Disease-causing air pollution remains high in pockets of America - particularly those where many low-income and African-American people live, a disparity highlighted in research presented at the annual meeting of the American Sociological Association in New York.

The nation's air on the whole has become cleaner in the past 70 years, but those benefits are seen primarily in whiter, higher-income areas, said Kerry Ard, an associate professor of environmental sociology at The Ohio State University, who will present her research today (Aug. 10, 2019.)

Ard used a variety of detailed data sources to examine air pollution and the demographics of the people who lived in 1-kilometer-square areas throughout a six-state region from 1995 through 1998. These are the four years after President Bill Clinton's 1994 executive order that focused attention on the environmental and health effects of federal actions on minority and low-income populations. The act's goal was "achieving environmental protection for all communities."

The six-state area analyzed in the Ohio State study, home to many aging and shuttered industrial plants, includes Illinois, Indiana, Michigan, Minnesota, Ohio and Wisconsin. These states make up the U.S. Environmental Protection Agency region with the highest level of unequal distribution of air toxins between whites and African-Americans.

In the four years included in her analysis, Ard found persistent air pollution hot spots that did not improve.

"We're seeing that these pollution hot spots are the same, year after year, and every time they are in low-income communities - often communities of color. This has implications for a wide array of health disparities - from preterm births and infant mortality to developmental delays in childhood, to heart and lung disease later in life," Ard said.

"Our results do not support that there was a perceivable mitigation of this gap after the executive order. In fact, we found that for every 1 percent increase in low-income African Americans living in an area, the odds that an area would become a hot spot grew significantly. This was also true, but to a lesser extent, for increases in low-income white populations."

Previous research has shown that despite widespread reductions in air pollution, blacks are still experiencing twice the health risk from air pollution than whites.

This isn't particularly surprising given that many blacks moved north toward industry - and jobs - during the Great Migration of African Americans from southern rural states, Ard said. Though many of the older, more-harmful plants have closed, others remain open and are often grandfathered into older regulatory standards that aren't as strict as those imposed on newer companies, she said.

Ard said that efforts to control pollution aren't going far enough to begin to eliminate the air-quality disparities and the health inequities to which they contribute. Ard, who is part of Ohio State's Institute for Population Research, recently published a textbook chapter focusing on this work.

"We really need to look at older industrial plants and how they are being regulated and how enforcement is happening in these areas," she said.

Air pollution is known to cause an array of health problems, but even those links aren't as well-understood as they should be because most efforts focus generically on fine particulate matter or on single toxins, rather than combinations that have the potential to inflict more harm, Ard said. Fine particulate matter refers to small, lightweight particles in the air that easily make their way into the lungs and sometimes the bloodstream and are known to trigger and worsen a host of diseases. But what, specifically, is in that matter is significant, and should be analyzed to steer policies aimed at protecting human health, Ard said.

In addition to tightening up air-quality standards for all polluters - and specifically going after the worst chemicals or combinations of chemicals - policymakers should consider efforts such as replanting trees in blighted areas in an effort to improve air quality, Ard said.

Patients with type 2 diabetes improve their ability to regulate blood sugar levels if they eat food with a reduced carbohydrate content and an increased share of protein and fat. This is shown by a recent study conducted at Bispebjerg Hospital in collaboration with, among other partners, Aarhus University and the Department of Nutrition, Exercise and Sports at the University of Copenhagen. The findings are contrary to the conventional dietary recommendations for type 2 diabetics.

Nutritional therapy is important to treat the type 2 diabetes optimally, but the recommendations are unclear. According to the Danish Health Authority, up to 85% of newly diagnosed patients with type 2 diabetes are overweight, and they are typically advised to follow a diet focused on weight loss: containing less calories than they burn, low fat content and a high content of carbohydrates with a low 'glycaemic index' (which indicates how quickly a food affects blood sugar levels).

Reduced carbohydrate content - increase in protein and fat

A central aspect in the treatment of type 2 diabetes is the patient's ability to regulate their blood sugar levels, and new research now indicates that a diet with a reduced carbohydrate content and an increased share of protein and fat improves the patient's ability to regulate his or her blood sugar levels compared with the conventional dietary recommendations. In addition, it reduces liver fat content and also has a beneficial effect on fat metabolism in type 2 diabetics.

"The purpose of our study was to investigate the effects of the diet without 'interference' from a weight loss. For that reason, the patients were asked to maintain their weight. Our study confirms the assumption that a diet with a reduced carbohydrate content can improve patients' ability to regulate their blood sugar levels - without the patients concurrently losing weight," explains Senior Consultant, DMSc Thure Krarup, MD, from the Department of Endocrinology at Bispebjerg Hospital. He continues: "Our findings are important, because we've removed weight loss from the equation. Previous studies have provided contradictory conclusions, and weight loss has complicated interpretations in a number of these studies."

New dietary recommendations for type 2 diabetics in future

Based on the growing body of evidence, we might rethink the dietary recommendations for patients with type 2 diabetes, stresses Thure Krarup:

"The study shows that by reducing the share of carbohydrates in the diet and increasing the share of protein and fat, you can both treat high blood sugar and reduce liver fat content. Further intensive research is needed in order to optimise our dietary recommendations for patients with type 2 diabetes," says Thure Krarup, stressing that the findings should be confirmed in large-scale, long-term controlled trials.

The findings of the study have been published in the article "A carbohydrate-reduced high-protein diet improves HbA1c and liver fat content in weight stable subjects with type 2 diabetes: a randomized controlled trial" in the renowned scientific journal 'Diabetologia'.

Summary: What did the study show?

A diet with a reduced carbohydrate content, high protein content and moderately increased fat content improves glycaemic control (the ability to regulate blood sugar) by reducing blood sugar after meals and 'long-term blood sugar' (measured by 'HbA1c', which is a blood test used to measure the average blood sugar level over approximately the past two months).

A diet with a reduced carbohydrate content, a high protein content and a moderately increased fat content reduces liver fat content.

A diet with a reduced carbohydrate content may be beneficial to patients with type 2 diabetes - even if it does not lead to weight loss.

About the study

The study forms part of CutDM, which - supported by a grant of DKK 4 million from Arla Food for Health - examines whether a diet with reduced carbohydrate content and increased protein and fat content improves type 2 patients' blood sugar regulation.

28 patients with type 2 diabetes participated in the study over a total period of 12 weeks. For six weeks, the patients were given a conventional diabetes diet with a high carbohydrate content, and, for the other six weeks, they were given a diet with a reduced carbohydrate content, high protein content and moderately increased fat content. The patients were given the diet types in random order.

CHAMPAIGN, Ill. -- Researchers have found a way to use polymer printing to stretch and flatten twisted molecules so that they conduct electricity better. A team led by chemical and biomolecular engineers from the University of Illinois report their findings in the journal Science Advances.

Conjugated polymers are formed by the union of electron-rich molecules along a backbone of alternating single and double chemical bonds. The conjunction allows electricity to travel very quickly through a polymer, making it highly desirable for use in electrical and optical applications. This mode of transporting charges works so well that conjugated polymers are now poised to compete with silicon materials, the researchers said.

However, these polymers tend to contort into twisted spirals when they join, severely impeding charge transport.

"The flatness or planarity of a conjugated polymer plays a large role in its ability to conduct electricity," said chemical and biomolecular engineering professor Ying Diao, who led the study. "Even a slight twist of the backbone can substantially hinder the ability of the electrons to delocalize and flow."

It is possible to flatten conjugated polymers by applying an enormous amount of pressure or by manipulating their molecular structure, but both techniques are very labor-intensive, Diao said. "There really is no easy way to do this."

Postdoctoral researcher Kyung Sun Park and graduate student Justin Kwok noticed something while running printing experiments and flow simulations in Diao's lab. Polymers go through two distinct phases of flow during printing: The first phase occurs when capillary action pulls on the polymer ink as it begins to evaporate, and the second phase is the result of the forces imposed by the printing blades and substrate, the researchers said.

"Park and Kwok uncovered another phase that occurs during printing in which the polymers appear to have vastly different properties," Diao said. "This third phase occurs in between the two already-defined phases, and shows the polymers being stretched into planar shapes."

Not only are the polymers stretched and flattened in this third phase, but they also remain that way after precipitating out of solution, Diao said, making it possible to fine-tune printer settings to produce conjugated polymers for use in new, faster biomedical devices and flexible electronics.

"We are discovering a whole zoo of new polymer phases, all sensitive to the forces that take place during the printing process," Diao said. "We envision that these unexplored equilibria and flow-induced phases will ultimately translate into new conjugated polymers with exciting optoelectronic properties."

While women have made great strides in entering the workforce, running companies and getting elected to Congress, there remains a persistent gender gap in attitudes about equality between men and women, suggests a University of California, Davis, study.

Although the last half of the 1900s saw much progress, the trajectory of attitudes about gender equality slowed in recent decades as men began to work longer hours and take on increased responsibilities to get ahead at work, nudging their wives into more traditional roles at home. This influence on negative attitudes toward women's work was widespread and not limited to the women and men directly impacted. The decline in egalitarian attitude was starkest among highly educated, high-salaried white people in professional jobs, researchers said.

The phenomenon, in which men work 50 or more hours per week, is called "men's overwork."

The study will be presented on Saturday, Aug. 10, at the American Sociological Association Annual Meeting in New York. The paper, "Persistent Gender Gap, Shifting Racial & Educational Differentiations: Variations in Structural Influences on Gender Attitudes, 1977-2016," was written by Kelsey D. Meagher, a postdoctoral scholar, and Xiaoling Shu, a professor of sociology.

"Men's overwork depressed gender egalitarianism among the whole population, but had the strongest effect among the college-educated, who were more proximate to the rising demands of overwork among professional occupations," the researchers said. "We show how labor market dynamics work hand-in-hand with social classifications by race, gender, and education in shaping the contour of American gender ideology in the last four decades."

Looked at changes in labor market

Meagher and Shu looked at data from the General Social Survey for the years 1977-2016, seeking to learn how changes in the labor market affected attitudes of different demographic groups. The analytic sample consists of more than 26,000 U.S. individuals, both men and women, who are both black and white, ages 16 and older, who are single, married and with or without children, of various political ideologies and religions. Latinx, Asian and other races are not included in the research because of lack of adequate sample size. Participants answered a series of questions about their attitudes about women in politics, the workplace, men's and women's social roles, and other issues.

Researchers found that college-educated respondents report more egalitarian attitudes than less-educated respondents. The researchers also found a racial gap in attitudes about gender equality, with white people holding more conservative gender attitudes than their black peers.

Women, across the board, reacted more positively toward egalitarianism than men.

This gender gap has persisted in the last four decades despite large societal transformations in the United States, while education and racial gaps fluctuated with contextual economic forces.

Among the decades of the survey, support for gender equality increased in each decade, with a slowdown only in the 1990s -- when men's overwork increased -- with an upward trend starting again in the 2000s. This "stalled revolution" in the '90s affected all demographic groups. The last year of the survey, 2016, showed the highest rate of feelings of egalitarianism in the study group for almost every group except for blacks, whose attitudes of egalitarianism peaked in 2014.

As a medical emergency caused by severe cardiovascular diseases, myocardial infarction (MI) can inflict permanent and life-threatening damage to the heart. A joint research team comprising scientists from City University of Hong Kong (CityU) has recently developed a multipronged approach for concurrently rejuvenating both the muscle cells and vascular systems of the heart by utilizing two types of stem cells. The findings give hope to develop a new treatment for repairing MI heart, as an alternative to the existing complex and risky heart transplant for seriously-ill patients.

MI is a fatal disorder caused by a shortage of coronary blood supply to the myocardium. It leads to permanent loss of heart muscle cells (cardiomyocytes, CMs), and scar tissue formation, resulting in irreversible damage to cardiac function or even heart failure. With limited therapeutic options for severe MI and advanced heart failure, a heart transplant is the last resort. But it is very risky, costly and subject to limited suitable donors. Therefore, stem cell-based therapy has emerged as a promising therapeutic option.

Dr Ban Kiwon, a stem cell biologist from Department of Biomedical Sciences at CityU, has been focusing on developing novel stem cell-based treatments for cardiac regeneration. "Heart is an organ composed of cardiac muscles and blood vessels, where vessels are essential to supply oxygen and energy to the muscles. Since both cardiac muscles and vasculatures would be severely damaged following MI, the therapeutic strategies should focus on comprehensive repair of both at the same time. But so far the strategies only focus on either one," he explains.

In this regard, Dr Ban and his collaborators, including researchers from Konkuk University, The Catholic University of Korea, Pohang University of Science and Technology, and T&R Biofab in South Korea, have recently developed a multipronged approach. It aimed to concurrently rejuvenate both the heart muscles and the vasculatures by utilizing two major types of stem cells, namely human bone marrow derived mesenchymal stem cells (hMSCs) and cardiomyocytes derived from human induced pluripotent stem cells (hiPSC-CMs).

The hMSCs was employed in the study due to their prominent paracrine activity of secreting good proteins to promote the regeneration of blood vessels and the endothelial cell survival. And the hiPSC-CMs was utilized for their similarities with human primary CMs in terms of the expressions of cardiac-specific genes, structural proteins, ion channels, and more importantly, the spontaneous contraction.

First study of two distinct stem cell effects for cardiac repair

While several previous studies described the beneficial effects of either hiPSC-CMs or hMSCs on MI separately, this is the first study to simultaneously examine the effects of these two distinct stem cells in cardiac repair. The researchers have adopted a dual approach, in which the hMSCs and the hiPSC-CMs were delivered via two distinct routes. The hiPSC-CMs were intramyocardially injected directly into border zone of the rat's heart, while the hMSCs-loaded patch was implanted on top of the infarct area, like a bandage.

The results showed that this dual approach led to a significant improvement of cardiac function and enhancement of vessel formation on a MI heart. The implanted hMSC-loaded patch not only provided a micro-environment which enhanced vascular regeneration as expected, but also improved the retention of hiPSC-CMs, ultimately augmenting heart function and restoring the injured myocardium.

Moreover, histological analyses results demonstrated that the implantation of hMSC-loaded patch has promoted the functional maturation of injected hiPSC-CMs. They became more elongated and rectangular in cell shape, appeared to be more organized in order, which were typical morphological characteristics of matured adult CMs. Functional maturation of intramyocardially injected hiPSC-CMs is particularly important. It is because it can reduce potential risk of arrhythmias, meaning irregular heart contraction, which is a major cause of sudden cardiac death.

Application potential in cardiac regeneration and beyond

"We believe this novel dual approach can potentially provide translational and clinical benefit to the field of cardiac regeneration," said Dr Ban. "Based on the same principle, the protocol may also be utilized for repairing other organs including brain, liver and pancreas in which multiple types of stem cells are co-existing." The team is working on follow-up studies in larger animal model such as pigs. The patent application has been submitted.

The research findings were published in scientific journal Nature Communications, titled "Dual stem cell therapy synergistically improves cardiac function and vascular regeneration following myocardial infarction". Dr Ban, together with Dr Moon Sung-Hwan from Konkuk University School of Medicine and Professor Park Hun-Jun from The Catholic University of Korea, are the corresponding authors of the paper. The first authors are Park Soon-Jung from Konkuk University School of Medicine, Kim Ri Youn and PhD student Lee Sunghun from CityU and Park Bong-Woo from The Catholic University of Korea.

ST. LOUIS - During the mating season, male treehoppers--small plant feeding insects--serenade potential mates with vibrational songs sent through plant stems. If a female treehopper's interest is sparked, a male-female duet ensues until mating occurs.

Scientists know that there is a thermal window when the half-centimeter-long insects are active and temperature shifts can throw this delicate coordination off. For example, the songs produced by males to attract mates vary with temperature. At some temperatures, male treehoppers can even sound like different species, potentially confusing females, as female treehoppers use these songs to pick a good mate.

A Saint Louis University research team wanted to know if temperature variation, which is increasing with global warming, could have a disruptive effect on the insects' reproduction.

To find out, the team studied how temperature variation affects male vibrational songs and female preferences for these songs in an experiment recently published in The Journal of Evolutionary Biology.

Led by Kasey Fowler-Finn, Ph.D., assistant professor of biology at Saint Louis University, the team tested four groups of Enchenopa binotata treehoppers, each from a different location. They measured the frequency (i.e. pitch) of male vibrational songs and the frequency most preferred by females across a range of temperatures from 18 to 36 degrees Celsius.

The results showed a strong temperature effect on both male signals and female preferences with changes in male signals across temperatures being matched by similar changes in the songs that females prefer. Because the male and female insects responded to temperature shifts together, changes in temperature did not significantly influence predicted patterns of female mate choice. Thus, it seems unlikely that thermal sensitivity in male songs will disrupt mating as temperatures shift.

Fowler-Finn is encouraged by the treehoppers' resilience.

"At a time when we are increasingly concerned about how global warming will influence animals, these findings provide some hope that treehoppers will persist in the face of change."

In addition to their research on global warming's potential impact to insects and ecosystems, the study team also is partnering with the Saint Louis University Museum of Art (SLUMA) to help educate the public about the vital role and fascinating attributes of vibrationally singing insects through a sound installation exhibit open to the public that will open October 25.

Other researchers on the paper include Dowen Mae I. Jocson, Morgan E. Smeester, Noah T. Leith and Anthony Macchiano.

The study was funded by the National Science Foundation (grant number IOS -1656818.)

The paper's digital object identifier is: https://doi.org/10.1111/jeb.13506

Key Take-aways

Male treehoppers serenade potential mates with vibrational songs sent through plant stems and if female treehoppers' interest is sparked, male-female duets ensue until mating occurs.

A Saint Louis University research team wanted to know if temperature variation, as is increasing with global warming, could disrupt the insects' reproduction due to its effects on male songs.

The research team tested four groups of Enchenopa binotata treehoppers, measuring the frequency of male signals and the frequency most preferred by females across a range of temperatures from 18 to 36 degrees Celsius.

Though the results showed a strong temperature effect on both male signals and female preferences, changes in male signals across temperatures were matched by changes in female preferences. Because the male and female insects both responded to temperature shifts together, changes in temperature did not significantly influence female mate choice or disrupt mating.

URBANA, Ill. - Invasive silver carp have been moving north toward the Great Lakes since their accidental release in the 1970s. The large filter-feeding fish, which are known to jump from the water and wallop anglers, threaten aquatic food webs as well as the $7 billion Great Lakes fishery. But, for the past decade, the invading front hasn't moved past Kankakee. A new study, led by scientists at the University of Illinois, suggests that Chicago's water pollution may be a contributing to this lack of upstream movement.

"It's a really toxic soup coming down from the Chicago Area Waterway, but a lot of those chemicals go away near Kankakee. They might degrade or settle out, or the Kankakee River might dilute them. We don't really know what happens, but there's a stark change in water quality at that point. That's right where the invading front stops," says Cory Suski, associate professor in the Department of Natural Resources and Environmental Sciences and co-author of the study. "And this fish never stops for anything."

The researchers think the fish stall out at Kankakee because they are responding negatively to compounds in the water flowing downstream from Chicago. They formulated their hypothesis after reading a 2017 water quality report from the U.S. Geological Survey. USGS researchers tracked changes in water chemistry in a single pocket of water as it moved from Chicago downstream through the Illinois River. Right near Kankakee, many of the pharmaceuticals, volatile organic compounds, and wastewater indicators dropped off the charts.

Suski says many of these compounds have been shown in other studies to induce avoidance behaviors in fish, but his team didn't look at behavior. Instead, they examined gene expression patterns in blood and liver samples from silver carp at three locations along the Illinois River: at Kankakee, approximately 10 miles downstream near Morris, and 153 miles downstream near Havana.

"We saw huge differences in gene expression patterns between the Kankakee fish and the two downstream populations," Suski explains. "Fish near Kankakee were turning on genes associated with clearing out toxins and turning off genes related to DNA repair and protective measures. Basically, their livers are working overtime and detoxifying pathways are extremely active, which seem to be occurring at the cost of their own repair mechanisms. We didn't see that in either of the downstream populations."

Suski stresses that his study wasn't designed to demonstrate a cause-and-effect relationship between water pollution and silver carp movement, but the results hint at a compelling answer to a decade-old mystery. The researchers hope to follow up to show how the fish are metabolizing the pollutants, which will give them a better understanding of which compounds are having the biggest effects. Right now, it's a black box - the USGS study documented approximately 280 chemicals in the Chicago Area Waterway and downstream sites.

Regardless of which specific pollutants may be responsible for stopping silver carp - if that hypothesis is later proven - the results could have interesting implications for management.

"We're not saying we should pollute more to keep silver carp out of the Great Lakes. That's not it," Suski says. "Right now, things are stable, but that might not always be the case. There's a lot of work in Chicago to clean up the Chicago Area Waterway. Already, water quality is improving, fish communities are getting healthier. Through the process of improving the water quality, which we should absolutely be doing, there's a possibility that this chemical barrier could go away. We don't need to hit the panic button yet, but at least we should be aware."

Many phenomena of the natural world evidence symmetries in their dynamic evolution which help researchers to better understand a system's inner mechanism. In quantum physics, however, these symmetries are not always achieved. In laboratory experiments with ultracold lithium atoms, researchers from the Center for Quantum Dynamics at Heidelberg University have proven for the first time the theoretically predicted deviation from classical symmetry. Their results were published in the journal "Science".

"In the world of classical physics, the energy of an ideal gas rises proportionally with the pressure applied. This is a direct consequence of scale symmetry, and the same relation is true in every scale invariant system. In the world of quantum mechanics, however, the interactions between the quantum particles can become so strong that this classical scale symmetry no longer applies", explains Associate Professor Dr Tilman Enss from the Institute for Theoretical Physics. His research group collaborated with Professor Dr Selim Jochim's group at the Institute for Physics.

In their experiments, the researchers studied the behaviour of an ultracold, superfluid gas of lithium atoms. When the gas is moved out of its equilibrium state, it starts to repeatedly expand and contract in a "breathing" motion. Unlike classical particles, these quantum particles can bind into pairs and, as a result, the superfluid becomes stiffer the more it is compressed. The group headed by primary authors Dr Puneet Murthy and Dr Nicolo Defenu - colleagues of Prof. Jochim and Dr Enss - observed this deviation from classical scale symmetry and thereby directly verified the quantum nature of this system. The researchers report that this effect gives a better insight into the behaviour of systems with similar properties such as graphene or superconductors, which have no electrical resistance when they are cooled below a certain critical temperature.

INDIANAPOLIS -- Researchers have conducted a study in which mice voluntarily ate a dough containing THC, the primary psychoactive component in marijuana. That opens the door to additional studies that will help shed light on behavioral and physiological effects that occur in people when they eat food infused with marijuana.

The study is among the first to report on voluntary oral THC consumption in animals, a method of consumption that is similar to the way humans take the drug.

In a recently published paper in Drug and Alcohol Dependence, researchers at IUPUI and Indiana University Bloomington said they found the mice were less active, and their body temperatures were lower, after consuming the edible THC.

The researchers also noted that the effects of edible THC varied based on the subject's sex, said Michael Smoker, first author of the paper and an addiction neuroscience Ph.D. candidate in the lab of professor Stephen Boehm in the psychology department at IUPUI. The addiction neuroscience graduate program is a Purdue University program at IUPUI.

The study showed that mice will self-administer -- or voluntarily choose to consume -- behavioral-effective doses of edible THC, and do so repeatedly, Smoker said. The mice were given gradually increasing doses in a dough made from flour, sugar, salt, glycerol and THC.

Understanding the health effects of eating marijuana edibles is important, given the growing popularity of that method of consumption in states where marijuana has been legalized, Smoker said.

"People can buy cookies, candies and all sorts of things with THC in them. Back in the day, you had to make your own brownies, or something like that, and now they are becoming more widely available and increasing in popularity," he said.

Marijuana edibles can elicit extreme, adverse reactions, Smoker said. Many of the commercially made marijuana-based products have a relatively higher concentration of THC than does marijuana plant material. In some cases, people are unsure how much of a marijuana edible they should eat and end up eating more than they should.

Questions researchers want to answer include the impact of edibles on people's ability to think, whether there are any long-term consequences for someone who has been eating edibles repeatedly and then stops, and what the consequences are, if any, of a child accidentally eating a marijuana edible, Smoker said.

Researchers turned to mice to answer questions about edible forms of THC due to ethical barriers involving use of humans in studies and the lack of control over human subjects' prior exposure to THC and other drugs.

Mice have been used in studies previously to study the effects of marijuana, but figuring out a way for them to self-administer the drug, as humans do, has been notoriously difficult, Smoker said.

This may come as a shock, if you're moving fast enough. The shock being shock waves. A balloon's 'pop' is shock waves generated by exploded bits of the balloon moving faster than the speed of sound. Supersonic planes generate a much louder sonic 'boom,' also from shock waves. Farther out into the cosmos, a collapsing star generates shock waves from particles racing near the speed of light as the star goes supernova. Scientists are using supercomputers to get a better understanding of turbulent flows that interact with shock waves. This understanding could help develop supersonic and hypersonic aircraft, more efficient engine ignition, as well as probe the mysteries of supernova explosions, star formation, and more.

"We proposed a number of new ways in which shock turbulence interactions can be understood," said Diego Donzis, an associate professor in the Department of Aerospace Engineering at Texas A&M University. Donzis co-authored the study, "Shock-Turbulence Interactions at High Turbulence Intensities," published May of 2019 in the Journal of Fluid Mechanics. "We proposed that, instead of treating the shock as a discontinuity, one needs to account for its finite thickness as in real life which may be involved as a governing parameter in, for example, amplification factors," Donzis said.

The dominant theoretical framework for shock turbulence interactions goes back to the 1950s, developed by Herbert Ribner while at the University of Toronto, Ontario. His work supported the understanding of turbulence and shocks interactions with a linear, inviscid theory, which assumes the shock to be a true discontinuity. The entire problem can thus be reduced to something mathematically tractable, where the results depend only on the shock's Mach number, the ratio of a body's speed to the speed of sound in the surrounding medium. As turbulence goes through the shock, it is typically amplified depending on the Mach number.

Experiments and simulations by Donzis and colleagues suggested this amplification depends also on the Reynolds Number, a measure of how strong the turbulence is, and the turbulent Mach number. "We proposed a theory that combined all of these into a single parameter," Donzis said. "And when we proposed this theory a couple of years ago, we didn't have well-resolved data at very high resolution to test some of these ideas."

Enter Stampede2, an 18 petaflop supercomputer at the Texas Advanced Computing Center, part of The University of Texas at Austin. Stampede2 is the most powerful computer in the U.S. for open science research, where the results are made freely available. Donzis was awarded compute time on Stampede2 through XSEDE, the Extreme Science and Engineering Discovery Environment. Both Stampede2 and XSEDE are funded by the National Science Foundation.

"On Stampede2, we ran a very large data set of shock turbulence interactions at different conditions, especially at high turbulence intensity levels, with a degree of realism that is beyond what is typically found in the literature in terms of resolution at the small scales, in terms of the order of the scheme that we used," Donzis said. "Thanks to Stampede2, we can not only show how amplification factors scale, but also under what conditions we expect Ribner's theory to hold, and under what conditions our previously proposed scaling is the more appropriate one."

Study lead author Chang Hsin Chen added that, "We also looked at the structure of the shock and, through highly resolved simulations, we were able to understand how turbulence creates holes on the shock. This was only possible due to the computational power provided by Stampede2." Chen is a postdoctoral researcher in the National Aerothermochemistry Laboratory at Texas A&M University. His research focuses on compressible turbulence and shock waves, and high performance computational fluid dynamics.

Donzis furthered that "Stampede2 is allowing us to run simulations, some of them at unprecedented levels of realism, in particular the small-scale resolution that we need to study processes at the very small scales of turbulent flows. Some of these simulations run on half of the machine, or more, and sometimes they take months to run."

What's more, the scientists also explored the so-called shock jumps, which are abrupt changes in pressure and temperature as matter moves across a shock. "In this study we developed and tested a new theoretical framework to understand, for example, why an otherwise stationary shock starts moving when the incoming flow is turbulent," Donzis said. This implies that the incoming turbulence deeply alters the shock. "The theory predicts, and the simulations on Stampede2 confirm that the pressure jumps change, and how they do so when the incoming flow is turbulent. This is an effect that is actually not accounted for in the seminal work by Ribner, but now we can understand it quantitatively," Donzis said.

Making progress in understanding when turbulence meets shocks didn't come easy. Extreme resolution on the order of billions of grid points are needed to capture the sharp gradients of a shock at high Reynolds number. "While we are limited by how much we can push the parameter range on Stampede2 or any other computer for that matter, we have been able to cover a very large space in this parameter space, spanning parameter ranges beyond what has been done before," Donzis said.

The input/output (I/O) also turned out to be challenging in writing the data to disk at very large core counts. "This is one instance in which we took advantage of the Extended Collaborative Support Services (ECSS) from XSEDE, and we were able to successfully optimize our strategy," Donzis said. "We are now confident that we can keep increasing the size of our simulations with the new strategy and keep doing I/O at a reasonable computational expense."

Donzis is no stranger to XSEDE, which he's used for years back when it was called Teragrid, to develop his group's codes - starting with the LeMieux system at the Pittsburgh Supercomputing Center; Blue Horizon at the San Diego Supercomputer Center; Kraken at the National Institute for Computational Sciences; and now on Stampede1 and Stampede2 at TACC.

"A number of the successes that we have today are because of the continued support of XSEDE, and Teragrid, for the scientific community. The research we're capable of doing today and all the success stories are in part the result of the continuous commitment by the scientific community and funding agencies to sustain a cyberinfrastructure that allows us to tackle the greatest scientific and technological challenges we face and may face in the future. This is true not just for my group, but perhaps also for the rest of the scientific computing community in the US. I believe the XSEDE project and its predecessors in this sense have been a tremendous enabler," Donzis said.

Donzis is a firm believer that advances in high performance computing (HPC) translate directly to benefits for all of society. "Any impact in HPC will have repercussions in transportation, industrial processes, manufacturing, defense, essentially the everyday life of ordinary people, as most of our lives are infused with technology products and services that at some stage or another benefit from numerical computations of different scales," Donzis said. And advances in the understanding of turbulence impact a broad range of applications, he added.

Said Donzis: "Advances in the understanding of shock turbulence interactions could lead to supersonic and hypersonic flight, to make them a reality for people to fly in a few hours from here to Europe; space exploration; and even our understanding of the structure of the observable universe. It could help answer, why are we here? More down to Earth, understanding turbulence in compressible flows could lead to great improvements in combustion efficiency, drag reduction and general transportation."

Remote sensor technologies like cameras, GPS trackers, and weather stations have revolutionized biological data collection in the field. Now researchers can capture continuous datasets in difficult terrain, at a scale unimaginable before these technologies became available. But as this flood of data has rolled into laboratory computers around the world, researchers have found themselves without well-developed analytical tools to make sense of it all. In research presented in a recent issue of Applications in Plant Sciences, Dr. Greice Mariano and colleagues introduce a tool called RadialPheno to analyze leafing patterns of plants based on remote camera data.

Before the widespread use of remote sensing equipment for field data collection, manual observation by scientists was a laborious, monotonous, and error-prone task, yielding much smaller and more dubious datasets. This is perhaps particularly true of phenology---the study of the timing of developmental events like leafing, flowering, and fruiting---because solid phenological observation requires being in the right place at the right time.

"On-the-ground phenological observations are accomplished periodically, require much more labor, and rely on the people that perform the observations," explains Dr. Mariano, corresponding author on the article and currently a post-doctoral research fellow at OCAD University, Toronto, Canada. "On top of that, results are stored in spreadsheets, which does not allow interoperability between data, making it difficult to analyze the data."

The ability to obtain rich sets of observations by setting up relatively inexpensive remote cameras has changed all that. But these observations don't mean much unless they can be translated into integrated, tractable datasets that can yield meaningful insights. "Since remote monitoring is something new to phenology studies, there is a need to develop and improve methods for detecting changes in phenological series and data images, setting up standards," says Dr. Mariano, who conducted this research during her PhD at the Institute of Computing, University of Campinas, Brazil. "Thus, in this research we introduced RadialPheno as a tool to support phenology experts in their analyses."

To identify the needs of these phenology experts, Dr. Mariano and her team worked with researchers at the Phenology Laboratory at São Paulo State University (UNESP). Dr. Mariano investigated what they wanted to see from data visualization tools and the issues they experience with existing software. Based on this investigation, they "developed a tool focused on the visualization of temporal data, where the identification of recurrent events is the most important task. We also thought about the integration of the visualization with the common statistical methods used by the experts," explains Dr. Mariano. "We choose radial representation because those structures are useful for understanding cyclical events, such as phenological ones."

The team tested their new tool by measuring leafing patterns in the Brazilian cerrado, a vast savanna ecosystem dominated by a wet and dry season. "Many plant phenology studies in Brazil have been conducted on a cerrado savanna area, and a digital camera for near-surface monitoring was installed in that area," says Dr. Mariano. "Thus, we also have phenological data based on on-the-ground observations, which allowed us to validate our tool with both on-the-ground data and [camera-derived] data." The camera network they set up is part of a set of cameras installed in different areas called the Phenocam Network, which is available online.

Solid data about phenological patterns are more urgently needed than ever, as climate change alters the timing of events in ecosystems around the world with possibly dire consequences for ecological interactions. Fortunately, remote sensing technologies have made collecting these datasets possible; tools like RadialPheno can now make them more meaningful.

How do galaxies such as our Milky Way come into existence? How do they grow and change over time? The science behind galaxy formation has remained a puzzle for decades, but a University of Arizona-led team of scientists is one step closer to finding answers thanks to supercomputer simulations.

Observing real galaxies in space can only provide snapshots in time, so researchers who want to study how galaxies evolve over billions of years have to revert to computer simulations. Traditionally, astronomers have used this approach to invent and test new theories of galaxy formation, one-by-one. Peter Behroozi, an assistant professor at the UA Steward Observatory, and his team overcame this hurdle by generating millions of different universes on a supercomputer, each of which obeyed different physical theories for how galaxies should form.

The findings, published in the Monthly Notices of the Royal Astronomical Society, challenge fundamental ideas about the role dark matter plays in galaxy formation, how galaxies evolve over time and how they give birth to stars.

"On the computer, we can create many different universes and compare them to the actual one, and that lets us infer which rules lead to the one we see," said Behroozi, the study's lead author.

The study is the first to create self-consistent universes that are such exact replicas of the real one: computer simulations that each represent a sizeable chunk of the actual cosmos, containing 12 million galaxies and spanning the time from 400 million years after the Big Bang to the present day.

Each "Ex-Machina" universe was put through a series of tests to evaluate how similar galaxies appeared in the generated universe compared to the true universe. The universes most similar to our own all had similar underlying physical rules, demonstrating a powerful new approach for studying galaxy formation.

The results from the "UniverseMachine," as the authors call their approach, have helped resolve the long-standing paradox of why galaxies cease to form new stars even when they retain plenty of hydrogen gas, the raw material from which stars are forged.

Commonly held ideas about how galaxies form stars involve a complex interplay between cold gas collapsing under the effect of gravity into dense pockets giving rise to stars, while other processes counteract star formation.

For example, it is thought that most galaxies harbor supermassive black holes in their centers. Matter falling into these black holes radiates tremendous energies, acting as cosmic blowtorches that prevent gas from cooling down enough to collapse into stellar nurseries. Similarly, stars ending their lives in supernova explosions contribute to this process. Dark matter, too, plays a big role, as it provides for most of the gravitational force acting on the visible matter in a galaxy, pulling in cold gas from the galaxy's surroundings and heating it up in the process.

"As we go back earlier and earlier in the universe, we would expect the dark matter to be denser, and therefore the gas to be getting hotter and hotter. This is bad for star formation, so we had thought that many galaxies in the early universe should have stopped forming stars a long time ago," Behroozi said. "But we found the opposite: galaxies of a given size were more likely to form stars at a higher rate, contrary to the expectation."

In order to match observations of actual galaxies, Behroozi explained, his team had to create virtual universes in which the opposite was the case - universes in which galaxies kept churning out stars for much longer.

If, on the other hand, the researchers created universes based on current theories of galaxy formation - universes in which the galaxies stopped forming stars early on - those galaxies appeared much redder than the galaxies we see in the sky.

Galaxies appear red for two reasons. The first is apparent in nature and has to do with a galaxy's age - if it formed earlier in the history of the universe, it will be moving away faster, shifting the light into the red spectrum. Astronomers call this effect redshift. The other reason is intrinsic: - if a galaxy has stopped forming stars, it will contain fewer blue stars, which typically die out sooner, and be left with older, redder stars.

"But we don't see that," Behroozi said. "If galaxies behaved as we thought and stopped forming stars earlier, our actual universe would be colored all wrong. In other words, we are forced to conclude that galaxies formed stars more efficiently in the early times than we thought. And what this tells us is that the energy created by supermassive black holes and exploding stars is less efficient at stifling star formation than our theories predicted."

According to Behroozi, creating mock universes of unprecedented complexity required an entirely new approach that was not limited by computing power and memory, and provided enough resolution to span the scales from the "small" - individual objects such as supernovae - to a sizeable chunk of the observable universe.

"Simulating a single galaxy requires 10 to the 48th computing operations," he explained. "All computers on Earth combined could not do this in a hundred years. So to just simulate a single galaxy, let alone 12 million, we had to do this differently."

In addition to utilizing computing resources at NASA Ames Research Center and the Leibniz-Rechenzentrum in Garching, Germany, the team used the "Ocelote" supercomputer at the UA High Performance Computing cluster. Two-thousand processors crunched the data simultaneously over three weeks. Over the course of the research project, Behroozi and his colleagues generated more than 8 million universes.

"We took the past 20 years of astronomical observations and compared them to the millions of mock universes we generated," Behroozi explained. "We pieced together thousands of pieces of information to see which ones matched. Did the universe we created look right? If not, we'd go back and make modifications, and check again."

To further understand how galaxies came to be, Behroozi and his colleagues plan to expand the UniverseMachine to include the morphology of individual galaxies and how their shapes evolve over time.

HOUSTON - (Aug. 9, 2019) - Rice University chemists want to make a point: Nitrogen atoms are for squares.

The nitrogens are the point. The squares are the frames that carry them. These molecules are called azetidines, and they can be used as building blocks in drug design.

The Rice lab of chemist László Kürti introduced its azetidines in an Angewandte Chemie paper. The lab's goal is to establish a library of scaffolds for pharmaceutical design through the simple synthesis of a class of molecules that were previously hard to find in nature and very hard to copy.

Azetidines already appear in several drugs and are promising components in the development of treatments for neurological diseases like Parkinson's disease, Tourette's syndrome and attention deficit disorder, according to the researchers.

So there's value in making a fast, inexpensive synthetic route to azetidines with unprotected nitrogen atoms called NH-azetidines -- NH for nitrogen and hydrogen -- that were first found in several kinds of Pacific sea sponges and have more recently been made in arduous laboratory processes.

Rice graduate students Nicole Behnke and Kaitlyn Lovato, lead authors of the paper, quickly learned why there are so few references to synthetic NH-azetidines in the scientific literature.

It required more than 250 experiments for the students to optimize their process, which takes about 24 hours, including product purification. Azetidine molecules come in many configurations, but they all share the square motif, a four-atom "ring" that contains one nitrogen atom and three carbon atoms. This ring is heterocyclic -- that is, it contains at least two different elements.

Kürti noted the square ring is always connected to another ring via one shared carbon atom, a structure called a spiro azetidine. In this way, the two rings are perpendicular to each other, further isolating the highly reactive nitrogen for access by chemists. The nitrogen in the Rice lab's variations were often, though not always, paired with a hydrogen atom "cap" that still allows the nitrogen to react with outside agents.

"Dr. Kürti was inspired by the mechanism of a synthetic process called the Kulinkovich reaction, which is used to make three-membered all-carbon rings, called cyclopropanes, that have the heteroatom (the nitrogen or oxygen) on the outside," Lovato said.

"Once we started looking into making four-membered azetidines, we found that most of them didn't have the NH structures," she said. "The known synthetic methods predominantly yield azetidines in which the ring nitrogen atom is connected to a carbon outside of the ring, but the NH connectivity was hard to access directly. If there's a carbon there, the nitrogen is considered protected, but having the hydrogen there leaves it free to engage in further reactions."

"Once you make this NH heterocycle, you have the flexibility to put whatever you want on the nitrogen," Kürti said. "Or to leave it as it is."

A titanium reagent turned out to be a key middleman in the chemical reaction, allowing it to proceed quickly. "This metal complex mediates the overall transformation, and it's very good because titanium is non-toxic and very abundant," he said.

"It's commercially available and cheap," Behnke said. "If we don't have the titanium added to the flask, the reaction doesn't work."

The Rice team did not patent the process, Kürti said. "The reality is that synthetic organic chemists in academia can contribute a lot to biomedical sciences and pharmaceutical drug discovery when we develop a new mechanism or reaction," he said.

"Biotech and pharmaceutical companies can use the products of these reactions to build structurally diverse compound libraries and quickly test them for biological activities towards different cancer cell lines, pathogens or other important disease biochemical pathways they have assays for," Kürti said. "Once they have access to novel core structures like these spiro azetidines, it's up to medical chemists to decide what diverse functionalities they wish to add on."

Muhammed Yousufuddin, a lecturer of chemistry at the University of North Texas at Dallas, is co-author of the paper. Kürti is an associate professor of chemistry.

Rice University, the National Institutes of Health, the National Science Foundation (NSF), the Robert A. Welch Foundation, the Amgen Young Investigators Award, the Biotage Young Principal Investigator Award and an NSF Graduate Research Fellowship supported the research.