Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: evolution – Page 82

WHO Director-General Tedros Adhanom Ghebreyesus, PhD, said today that infections have been detected in 58 countries. Our World in Data lists 7,075 confirmed cases worldwide.

Testing is a challenge

“Testing remains a challenge, and it’s highly probable that there are a significant number of cases not being picked up,” he warned during a speech. “I plan to reconvene the Emergency Committee so they are updated on the current epidemiology and evolution of the outbreak, and implementation of counter measures.”

Read more | >

The architecture and evolution of planetary systems are shaped in part by stellar flybys. Within this context, we look at stellar encounters which are too weak to immediately destabilize a planetary system but are nevertheless strong enough to measurably perturb the system’s dynamical state. We estimate the strength of such perturbations on secularly evolving systems using a simple analytic model and confirm those estimates with direct N-body simulations. We then run long-term integrations and show that even small perturbations from stellar flybys can influence the stability of planetary systems over their lifetime. We find that small perturbations to the outer planets’ orbits are transferred between planets, increasing the likelihood that the inner planetary system will destabilize.

Read more | >

Evolution has developed very efficient molecular machines, for example for producing energy through rotation. Hendrik Dietz would like to harness these concepts to build his own molecular motors. His group has successfully demonstrated that they can encode and synthesize complex shapes using DNA origami, and have recently discovered how to reduce the cost for mass use and production. With his research, Dietz gets closer to his goal of revolutionizing nanotechnology with the capabilities of molecular motors, just like industry was revolutionized by electric and diesel motors.

. Can you remember playing with legos? Now imagine doing that with molecules. Prof. Hendrik Dietz, professor for experimental biophysics at TUM, runs a lab which does just that. Inspired by the rich functionalities of natural macromolecular assemblies such as enzymes, molecular motors, and viruses, the Dietz lab investigates how to build increasingly complex molecular structures. The goal is to build molecular devices and machines that can execute user-defined tasks. DNA origami in particular enables building nanodevices that can already be employed for making new discoveries in biomolecular physics and protein science. This talk was given at a TEDx event using the TED conference format but independently organized by a local community.

Read more | >

Dramatic expansion of the human cerebral cortex, over the course of evolution, accommodated new areas for specialized cognitive function, including language. Understanding the genetic mechanisms underlying these changes, however, remains a challenge to neuroscientists.

A team of researchers in Japan has now elucidated the mechanisms of cortical evolution. They used molecular techniques to compare the in mouse and monkey brains.

Using the technique called in situ hybridization to visualize the distribution of mRNA transcripts, Okano, Shimogori and their colleagues examined the expression patterns of genes that are known to regulate development of the . They compared these patterns to those of the same genes in the brain of the common marmoset. They found that most of the genes had similar expression patterns in mice and marmosets, but that some had strikingly different patterns between the two species. Notably, some areas of the visual and prefrontal showed expression patterns that were unique to marmosets.

Read more | >

A new UC Davis-led study sheds light on cell type-specific biomarkers, or signs, of melanoma. The research was recently published in the Journal of Investigative Dermatology.

Melanoma, the deadliest of the common skin cancers, is curable with and treatment. However, diagnosing clinically and under the microscope can be complicated by what are called melanocytic nevi—otherwise known as birth marks or moles that are non-cancerous. The development of melanoma is a multi-step process where “melanocytes,” or the cells in the skin that contain melanin, mutate and proliferate. Properly identifying melanoma at an early stage is critical for improved survival.

“The biomarkers of early melanoma evolution and their origin within the tumor and its microenvironment are a potential key to early diagnosis of melanoma,” said corresponding author of the study Maija Kiuru, associate professor of clinical dermatology and pathology at UC Davis Health. “To unravel the mystery, we used high-plex spatial RNA profiling to capture distinct gene expression patterns across cell types during melanoma development. This approach allows studying the expression of hundreds or thousands of genes without disrupting the native architecture of the tumor.”

Read more | >

The motion of a tiny number of charged particles may solve a longstanding mystery about thin gas disks rotating around young stars, according to a new study from Caltech.

These features, called , last tens of millions of years and are an early phase of solar system evolution. They contain a small fraction of the mass of the star around which they swirl; imagine a Saturn-like ring as big as the solar system. They are called accretion disks because the gas in these disks spirals slowly inward toward the star.

Scientists realized long ago that when this inward spiraling occurs, it should cause the radially inner part of the disk to spin faster, according to the law of the conservation of angular momentum. To understand conservation of angular momentum, think of spinning figure skaters: when their arms are outstretched, they spin slowly, but as they draw their arms in, they spin faster.

Read more | >

NLM’s NCBI is introducing the Comparative Genome Viewer (CGV), an easy-to-use visualization tool that helps you quickly compare eukaryotic genome assemblies and easily identify genomic changes that may be significant to biology and evolution. With the new CGV you can view and compare the alignment between two assemblies to see differences in genomic sequence and structure, including deletions, inversions, and translocations. Currently, you can compare assemblies from over 50 annotated animal and plant genomes.

Read more | >

In a trio of studies published on June 27 in the journal Nature Microbiology 0, researchers at The University of Texas at Austin have discovered “fingerprints” of mysterious viruses hidden in an ancient group of microbes that may include the ancestors of all complex life on Earth: from fungi to plants to humans.

Ths discovery is significant; it explores the hypothesis that viruses were imperative to the evolution of humans and other complex life forms.

These microbes – known as Asgard archaea after the abode of the gods in Norse mythology – are usually found in the frigid sediments deep in the ocean and in boiling springs, and existed on Earth before the first eukaryotic cells, which carry their DNA inside a nucleus.

Read more | >