Lifeboat Foundation

June 10 marks the first solar eclipse of any kind viewable in North America since 2017.

The ring of fire annular solar eclipse in June is the first solar eclipse viewable in North America since 2017. Here’s how to watch and what makes it special.

While carrying out high-throughput chromosome conformation capture (Hi-C) analysis on stage 8 (s8) X. tropicalis embryos, we noticed that chromatin interactions plotted at 100-kilobase (kb) resolution using the reference genome v.9.1 showed inversions, misplacements and gaps in nearly every chromosome (Fig. 1a and Extended Data Fig. 1). Thus, to accurately characterize the genome folding patterns in X. tropicalis, we conducted a de novo genome assembly of X. tropicalis using Hi-C and single-molecule sequencing^42,43,44 (Fig. 1b). The newly assembled genome fixed most misplacements, inversions and gaps (Fig. 1c, d, Extended Data Fig. 2 and Supplementary Fig. 1). This new version of the genome was also longer (Supplementary Table 1 and Fig. 1e) and centromere interactions can now be detected (Supplementary Fig. 2). During the preparation of this work, v.10.0 of the X. tropicalis genome was released. While both v.10.0 and our assembly fixed major errors, both versions are still flawed with visually identifiable errors (Supplementary Fig. 1; blue and green arrows). A comparison of the three versions is shown in Supplementary Table 1. Conclusions from the following analyses are the same whether we used v.10.0 or our assembled genome.

To examine when the 3D chromatin architecture is established in X. tropicalis, we generated in situ Hi-C maps on hand-picked s8 embryos (Fig. 2a). A high-resolution (5-kb) inspection of chromatin contact heatmaps failed to reveal any distinct patterns (Fig. 2b), indicating the lack of structural organization before MBT. Next, we determined whether chromatin structures will emerge when rapid synchronized cell division ends by carrying out in situ Hi-C on s9 embryos. Although weak, TAD-like structures appeared across chromatin contact heatmaps (Fig. 2b), suggesting that TAD structures start forming as MBT begins in X. tropicalis.

We continued to examine the changes in chromatin conformation at later developmental stages (stages 10, 11, 12, 13, 15, 17, and 23) after major ZGA (Fig. 2b). TAD boundaries increased progressively from 2471 at s9 to 3000 at s11 (Extended Data Fig. 3a, b). This level was maintained throughout the later developmental stages and with relatively stable median TAD sizes (Extended Data Fig. 3a, b). Consistent with this pattern, the percentage of the genome folded into TADs positively correlated with the number of TADs established at each stage (Extended Data Fig. 3c). Overall, TAD borders were stable during development (Fig. 2c) and contained a high level of gene expression (Extended Data Fig. 3D, e).

In a new study published in ‘Nature’, scientists have discovered a major hallmark of the aging process and how to reverse the accompanying cognitive decline.

A new technology could dramatically improve the safety of lithium-ion batteries that operate with gas electrolytes at ultra-low temperatures. Nanoengineers at the University of California San Diego developed a separator—the part of the battery that serves as a barrier between the anode and cathode—that keeps the gas-based electrolytes in these batteries from vaporizing. This new separator could, in turn, help prevent the buildup of pressure inside the battery that leads to swelling and explosions.

“By trapping gas molecules, this separator can function as a stabilizer for volatile electrolytes,” said Zheng Chen, a professor of nanoengineering at the UC San Diego Jacobs School of Engineering who led the study.

The new separator also boosted battery performance at ultra–low temperatures. Battery cells built with the new separator operated with a high capacity of 500 milliamp-hours per gram at-40 C, whereas those built with a commercial separator exhibited almost no capacity. The battery cells still exhibited high capacity even after sitting unused for two months—a promising sign that the new separator could also prolong shelf life, the researchers said.

Army researchers have developed a pioneering framework that provides a baseline for the development of collaborative multi-agent systems.

The framework is detailed in the survey paper “Survey of recent multi-agent reinforcement learning algorithms utilizing centralized training,” which is featured in the SPIE Digital Library. Researchers said the work will support research in reinforcement learning approaches for developing collaborative multi-agent systems such as teams of robots that could work side-by-side with future soldiers.

“We propose that the underlying information sharing mechanism plays a critical role in centralized learning for multi-agent systems, but there is limited study of this phenomena within the research community,” said Army researcher and computer scientist Dr. Piyush K. Sharma of the U.S. Army Combat Capabilities Development Command, known as DEVCOM, Army Research Laboratory. “We conducted this survey of the state-of-the-art in reinforcement learning algorithms and their information sharing paradigms as a basis for asking fundamental questions on centralized learning for multi-agent systems that would improve their ability to work together.”

It’s on track to be the first country to legalize fully autonomous “robotaxis,” beating out the United States and China.

Microsoft president: Orwell’s 1984 could happen in 2024.

Tech executives warned that democracy has to win the AI arms race, in a new BBC Panorama.

Therapy increases survival in grim diagnosis.

Circumstantial evidence could point to a mind-blowing solution to an antimatter mystery—or to the need for better space-based particle physics experiments.