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Tuesday, May 16, 2023

Out of this world control on Ice Age cycles

NATIONAL INSTITUTES OF NATURAL SCIENCES

Artist's impression of how astronomical forces affect the Earth's motion, climate, and ice sheets — IMAGE: ARTIST'S IMPRESSION OF HOW ASTRONOMICAL FORCES AFFECT THE EARTH'S MOTION, CLIMATE, AND ICE SHEETS. view more
CREDIT: NAOJ

A research team, composed of climatologists and an astronomer, have used an improved computer model to reproduce the cycle of ice ages (glacial periods) 1.6 to 1.2 million years ago. The results show that the glacial cycle was driven primarily by astronomical forces in quite a different way than it works in the modern age. These results will help us to better understand the past, present, and future of ice sheets and the Earth’s climate.

Earth’s orbit around the Sun and its spin axis orientation change slowly over time, due to the pull of gravity from the Sun, the Moon, and other planets. These astronomical forces affect the environment on Earth due to changes in the distribution of sunlight and the contrast between the seasons. In particular, ice sheets are sensitive to these external forces resulting in a cycle between glacial and interglacial periods.

The present-day glacial-interglacial cycle has a period of about 100,000 years. However, the glacial cycle in the early Pleistocene (about 800,000 years ago) switched more rapidly, with a cycle of about 40,000 years. It has been believed that astronomical external forces are responsible for this change, but the details of the mechanism have not been understood. In recent years, it has become possible to investigate in more detail the role of astronomical forces through the refinement of geological data and the development of theoretical research.

A team led by Yasuto Watanabe at the University of Tokyo focused on the early Pleistocene Epoch from 1.6 to 1.2 million years ago using an improved climate computer model. Astronomical forces based on modern state-of-the-art theory are considered in these simulations. The large numerical simulations in this study reproduce well the glacial cycle of 40,000-year of the early Pleistocene as indicated by the geological record data.

From analysis of these simulation results, the team has identified three facts about the mechanisms by which astronomical forces caused changes in climate in those times. (1) The glacial cycle is determined by small differences in the amplitude of variation of the spin axis orientation and the orbit of the Earth. (2) The timing of deglaciation is determined mainly by the position of the summer solstice on its orbit, which is at perihelion, not only by the effect of periodical change of the tilt of the Earth’s axis. (3) The timing of the change in the spin axis orientation and the position of the summer solstice on its orbit determines the duration of the interglacial period.

“As geological evidence from older times comes to light, it is becoming clear that the Earth had a different climatic regime than it does today. We must have a different understanding of the role of astronomical forcing in the distant past,” says Takashi Ito from the National Astronomical Observatory of Japan, a member of this research team who led the discussion on astronomical external forces. “The numerical simulations performed in this study not only reproduce the Pleistocene glacial-interglacial cycle well, but also successfully explain the complex effects of how astronomical forcing drove the cycle at that time. We can regard this work as a starting point for the study of glacial cycles beyond the present day Earth.”

These results appeared as Watanabe Y. et al. “Astronomical forcing shaped the timing of early

Pleistocene glacial cycles” in Communications Earth & Environment on May 15, 2023.

JOURNAL

Communications Earth & Environment

DOI

10.1038/s43247-023-00765-x

METHOD OF RESEARCH

Computational simulation/modeling

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Astronomical forcing shaped the timing of early Pleistocene glacial cycles

ARTICLE PUBLICATION DATE

15-May-2023

WFIRM bioprinting research makes history when it soars to the ISS

Second private astronaut mission by Axiom Space targeting May launch

Business Announcement

ATRIUM HEALTH WAKE FOREST BAPTIST

WFIRM Gyroid Shaped Construct — IMAGE: WFIRM GYROID SHAPED CONSTRUCT view more
CREDIT: WFIRM

WINSTON-SALEM, NC – MAY 15, 2023 – The Wake Forest Institute for Regenerative Medicine (WFIRM) will make history this month when the first bioprinted solid tissue constructs soar to the International Space Station (ISS) on board the next all private astronaut mission by commercial space leader Axiom Space.

The Axiom Mission 2 (Ax-2) launch by Houston-based Axiom Space is launching from Florida’s Kennedy Space Center. The crew will conduct extensive scientific research experiments including WFIRM’s vascularized tissue research – which won first place in the NASA Vascular Tissue Challenge in 2021.

Liver and kidney tissue constructs bioprinted by WFIRM scientists will be on the May Ax-2 launch from Kennedy Space Center in Florida to the ISS in low-Earth orbit. The tissues will be studied for 10 days to evaluate the vascularization of thick tissue in microgravity and the effectiveness of this platform technology for other tissue types.

“This launch marks an important next step for our regenerative medicine research related to vascularized tissue,” said WFIRM Director Anthony Atala, MD. “This is an opportunity to develop an interim/early step toward creating solid tissues/partial organs for transplantation into patients in the future to address the organ shortage.”

Previous research on ISS using cells in low-Earth orbit has included both 2D and small 3D cultures. These prior experiments have shown that cells exposed to micro-gravity undergo both genetic and functional changes, including increased motility and proliferation. Studying these larger tissue constructs in microgravity will help inform the researchers not only with regards to how the liver/kidney cells respond, but also as to how an endothelial coating of blood vessel cells will react to the altered atmosphere.

One of the most important factors in developing larger organ models is cell adhesion. This allows the cells to stick to each other or the material they are embedded in, creating multi-dimensional structures such as organoids and full tissues. This model will allow WFIRM researchers to delve into the specifics of cell adhesion in determining the overall 3D structure necessary to organ survival.

“While many components of cell adhesion have been studied in microgravity, every time the model changes it allows for new insight as to how changes in cell adhesion may affect human organs in microgravity,” said James Yoo, MD, PhD, professor of regenerative medicine at WFIRM. “We look forward to determining how this bioprinted tissue will model a more complete version of adherence reactions to microgravity.”

The WFIRM team will employ a digital light processing bioprinter that uses a light-curing resin made up of tissue cells to print the liver and kidney constructs into a unique-shaped architecture called a gyroid. The interconnected channels of the gyroid shape allow for a uniform flow of nutrition media throughout the inner surfaces of these cell-laden tissue constructs.

To prepare for launch, liver and kidney tissue constructs will be bioprinted independently. To assist in the maturation of the tissues, samples will be placed on flow, continuously exposed to perfused media for either five or ten days prior to launch. They will then be placed in transparent cell-culture containers that provide a closed system in which to grow the cells while on orbit.

While the research is taking place on the ISS, WFIRM research associates will be monitoring a duplicate set of samples on Earth. These will act as a gravity control and will undergo the same processes as those on the ISS. The team will be in communication during mission operations conducted on the ISS so the same activity timeline can be applied to the control constructs in the WFIRM lab.

While the primary focus for the team is on creating tissue constructs that can be used as a bridge to transplantation, they can also be used as a model system for human disease and testing potential new therapies as well as for studying health effects and developing potential countermeasures for astronauts who spend a significant amount of time in space.

“Taking the first steps toward future in-space manufacturing applications for biomedical products on Ax-2 is exciting,” said Jana Stoudemire, Director, In Space Manufacturing, Axiom Space. “We are pleased to work with recognized leaders from the WFIRM team, highly regarded for their excellence in tissue engineering and translational regenerative medicine, to advance this important work as we build a future commercial space economy together.”

WFIRM team members include WFIRM Director Anthony Atala, MD; James Yoo, MD, PhD; Sang Jin Lee, PhD; Colin Bishop, PhD; Kelsey Willson and Timothy Dombroski, PhD graduate students.

About the Wake Forest Institute for Regenerative Medicine: The Wake Forest Institute for Regenerative Medicine is recognized as an international leader in translating scientific discovery into clinical therapies, with many world firsts, including the development and implantation of the first engineered organ in a patient. Over 400 people at the institute, the largest in the world, work on more than 40 different tissues and organs. A number of the basic principles of tissue engineering and regenerative medicine were first developed at the institute. WFIRM researchers have successfully engineered replacement tissues and organs in all four categories – flat structures, tubular tissues, hollow organs and solid organs – and 16 different applications of cell/tissue therapy technologies, such as skin, urethras, cartilage, bladders, muscle, kidney, and vaginal organs, have been successfully used in human patients. The institute, which is part of Wake Forest School of Medicine, is located in the Innovation Quarter in downtown Winston-Salem, NC, and is driven by the urgent needs of patients. The institute is making a global difference in regenerative medicine through collaborations with over 400 entities and institutions worldwide, through its government, academic and industry partnerships, its start-up entities, and through major initiatives in breakthrough technologies, such as tissue engineering, cell therapies, diagnostics, drug discovery, biomanufacturing, nanotechnology, gene editing and 3D printing.

About Axiom Space: Axiom Space, the premier provider o human spaceflight services and developer of human-rated space infrastructure, is guided by the vision of a thriving home in space that benefits every human, everywhere. Axiom is opening new markets in low-Earth orbit through operating end-to-end missions to the International Space Station while privately developing its successor – a permanent commercial destination in Earth’s orbit that will sustain human growth off the planet and bring untold benefits back home. More information about Axiom and its generational mission can be found at www.axiomspace.com

Can’t find your phone? There’s a robot for that

Robots can help find objects you’ve lost, thanks to new ‘artificial memory’

Reports and Proceedings

UNIVERSITY OF WATERLOO

Fetch — IMAGE: FETCH, THE ROBOT USED IN THE RESEARCH view more
CREDIT: UNIVERSITY OF WATERLOO

Engineers at the University of Waterloo have discovered a new way to program robots to help people with dementia locate medicine, glasses, phones and other objects they need but have lost.

And while the initial focus is on assisting a specific group of people, the technology could someday be used by anyone who has searched high and low for something they’ve misplaced.

“The long-term impact of this is really exciting,” said Dr. Ali Ayub, a post-doctoral fellow in electrical and computer engineering. “A user can be involved not just with a companion robot but a personalized companion robot that can give them more independence.”

Ayub and three colleagues were struck by the rapidly rising number of people coping with dementia, a condition that restricts brain function, causing confusion, memory loss and disability. Many of these individuals repeatedly forget the location of everyday objects, which diminishes their quality of life and places additional burdens on caregivers.

Engineers believed a companion robot with an episodic memory of its own could be a game-changer in such situations. And they succeeded in using artificial intelligence to create a new kind of artificial memory.

The research team began with a Fetch mobile manipulator robot, which has a camera for perceiving the world around it.

Next, using an object-detection algorithm, they programmed the robot to detect, track and keep a memory log of specific objects in its camera view through stored video. With the robot capable of distinguishing one object from another, it can record the time and date objects enter or leave its view.

Researchers then developed a graphical interface to enable users to choose objects they want to be tracked and, after typing the objects’ names, search for them on a smartphone app or computer. Once that happens, the robot can indicate when and where it last observed the specific object.

Tests have shown the system is highly accurate. And while some individuals with dementia might find the technology daunting, Ayub said caregivers could readily use it.

Moving forward, researchers will conduct user studies with people without disabilities, then people with dementia.

A paper on the project, Where is my phone? Towards developing an episodic memory model for companion robots to track users’ salient objects, was presented at the recent 2023 ACM/IEEE International Conference on Human-Robot Interaction.

Smartphone use goes up in city parks, but down in forests

Nature can curb smartphone use, but go beyond your local park—where screentime increases—and find some wild nature, new research suggests

Peer-Reviewed Publication

UNIVERSITY OF VERMONT

While a visit to the great outdoors is a common prescription for reducing screen use, a pioneering new study finds that time outdoors doesn’t always reduce smartphone screentime.

The new research, which tracked smartphone activity of 700 study participants for two years, reveals that participants’ smartphone activity actually increased during visits to city parks and other urban green spaces.

With smartphone use rising worldwide, the study clearly identifies a powerful way to reduce screen time: participants who visited nature reserves or forests saw significant declines in screentime over the first three hours, compared to visiting urban locations for the same amount of time.

The study, published in the journal Environment and Behavior, is the first to show that young adults now spend far more time on their smartphone screens than in nature, the researchers say. Given unparalleled access to participants’ devices, the team found that young adults in the study spent over twice as much time on their smartphones as they spent outdoors.

“Greentime, or time outdoors, has long been recommended as a way to restore our attention from the demands of daily life, yet before our study, little was known about whether nature provides a way for people to disconnect from the mobile devices that now follow us into the great outdoors,” said lead author Kelton Minor, a Postdoctoral Research Scientist at Columbia University’s Data Science Institute. “While past research suggested that short trips to city parks might provide a digital detox, we saw texting and phone calls actually go up. It was really the longer visits to wilder areas, like forests or nature preserves, that helped people get off their screens and wrest back their attention from their smartphones.”

A key advance of the study is the novelty of data’ richness compared to other smartphone studies, where participants typically self-report their smartphone use or environmental behaviors. In this study, participants consented to share their smartphone data—over 2.5 million privacy-preserving logs of activity from texts, calls and screen time—for science.

“Smartphones have an incredibly powerful pull on our attention, which will undoubtedly increase in the future—that’s what many technology companies are working on,” says University of Vermont (UVM) co-author Chris Danforth, a Gund Fellow who will co-lead a new $20M big data project on the science of storytelling. “Given the reported connections between mental health and our digital life, we need more studies like this to help establish ways to encourage a healthier relationship with technology.”

Discussing their findings, the researchers theorize that urban greenspace may instead be useful in enhancing remote social ties—hence the increase in texts and phone calls in urban parks—but may interrupt the individual’s opportunity to utilize the attention-restoring properties of nature.

Increased smartphone use has been linked to rising cases in anxiety, depression, and sleep problems, especially in younger generations. At the same time, research from UVM and others has shown that nature has restorative benefits for our minds and bodies that deliver a sense of joy comparable to a holiday like Thanksgiving or New Year’s. Researchers theorize that the visual and sensory experiences of nature help strengthen individuals’ ability to better focus on life beyond their smartphones.

The study is the first to compare time spent on smartphone screens to time spent in outdoor green spaces,according to the researchers. They found that even the young adults who typically used their smartphones the most reduced their usage in nature areas, providing evidence that more wild greentime may provide a digital break for even the most connected.

The study—Nature Exposure is Associated With Reduced Smartphone Use—is by an international team of scientists from the U.S. and Europe, including Columbia University, University of Vermont, University of Colorado Boulder, University of Copenhagen, and Technical University of Denmark. Researchers included Kelton Minor, Kristoffer Lind Glavind, Aaron J. Schwartz, Christopher M. Danforth, Sune Lehmann, and Andreas Bjerre-Nielsen.