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Nov 2, 2022

Physicists see light waves moving through a metal

Posted by in categories: materials, quantum physics

When we encounter metals in our day-to-day lives, we perceive them as shiny. That’s because common metallic materials are reflective at visible light wavelengths and will bounce back any light that strikes them. While metals are well suited to conducting electricity and heat, they aren’t typically thought of as a means to conduct light.

But in the burgeoning field of , researchers are increasingly finding examples that challenge expectations about how things should behave. In new research published in Science Advances, a team led by Dmitri Basov, Higgins Professor of Physics at Columbia University, describes a metal capable of conducting light. “These results defy our daily experiences and common conceptions,” said Basov.

The work was led by Yinming Shao, now a postdoc at Columbia who transferred as a Ph.D. student when Basov moved his lab from the University of California San Diego to New York in 2016. While working with the Basov group, Shao has been exploring the optical properties of a semimetal material known as ZrSiSe. In 2020 in Nature Physics, Shao and his colleagues showed that ZrSiSe shares electronic similarities with graphene, the first so-called Dirac material discovered in 2004. ZrSiSe, however, has enhanced electronic correlations that are rare for Dirac semimetals.

Nov 2, 2022

The cosmologist who claims to have evidence for the multiverse

Posted by in categories: cosmology, mathematics, quantum physics

HOW did our universe begin? This is among the most profound questions of all, and you would be forgiven for thinking it is impossible to answer. But Laura Mersini-Houghton says she has cracked it. A cosmologist at the University of North Carolina at Chapel Hill, she was born and raised under communist dictatorship in Albania, where her father was considered ideologically opposed to the regime and exiled. She later won a Fulbright scholarship to study in the US, forging a career in cosmology in which she has tackled the origins of the universe – and made an extraordinary proposal.

Mersini-Houghton’s big idea is that the universe in its earliest moments can be understood as a quantum wave function – a mathematical description of a haze of possibilities – that gave rise to many diverse universes as well as our own. She has also made predictions about how other universes would leave an imprint upon our own. Those ideas have been controversial, with some physicists arguing that her predictions are invalid. But Mersini-Houghton argues that they have been confirmed by observations of the radiation left over from the big bang, known as the cosmic microwave background.

Nov 2, 2022

Dr. Jacob Hanna, MD, Ph.D. — Synthetic Embryo R&D In Regenerative Medicine & Developmental Biology

Posted by in categories: biotech/medical, computing, genetics, life extension

(https://hannalabweb.weizmann.ac.il/) is a Senior Scientist and Professor in the Department of Molecular Genetics at the Weizmann Institute of Science in Israel, where his lab, and the interdisciplinary group of scientists within it, are focused on understanding the complexity of early embryonic stem cell biology and early developmental dynamics, as well as advancing human disease modeling.

More specifically, Dr. Hanna’s lab investigates the detailed process of cellular reprogramming, in which induced pluripotent stem cells are generated from somatic cells, and they investigate how pluripotency is maintained throughout development in mouse and human. In their studies they employ a diverse arsenal of biological experimentation methods, high throughput screening, advanced microscopy and genomic analyses seeking to combine biological experimentation with computational biology, theory and modeling, to elucidate various biological questions.

Continue reading “Dr. Jacob Hanna, MD, Ph.D. — Synthetic Embryo R&D In Regenerative Medicine & Developmental Biology” »

Nov 2, 2022

Sites in the brain where RNA is edited could help our understanding of neurodevelopment and disease

Posted by in categories: biotech/medical, genetics, life extension, neuroscience

Mount Sinai researchers have cataloged thousands of sites in the brain where RNA is modified throughout the human lifespan in a process known as adenosine-to-inosine (A-to-I) editing, offering important new avenues for understanding the cellular and molecular mechanisms of brain development and how they factor into both health and disease.

In a study published in Cell Reports, the team described how the rate of RNA editing in the brain increases as individuals age, with implications for dissecting the pathology of altered A-to-I editing across a range of neurodevelopmental and aging disorders.

“Our work provides more nuanced and accurate insights into the contribution of RNA modifications by A-to-I editing during human brain development,” says senior author Michael Breen, Ph.D., Assistant Professor of Psychiatry, and Genetics and Genomic Sciences, at the Icahn School of Medicine at Mount Sinai, and a member of the Seaver Center for Autism Research and Treatment.

Nov 2, 2022

Anthropologists find new ways female bones are permanently altered after giving birth

Posted by in category: biotech/medical

Reproduction permanently alters females’ bones in ways not previously known, a team of anthropologists has found. Its discovery, based on an analysis of primates, sheds new light on how giving birth can permanently change the body.

“Our findings provide additional evidence of the profound impact that reproduction has on the female organism, further demonstrating that the skeleton is not a static organ, but a dynamic one that changes with ,” explains Paola Cerrito, who led the research as a doctoral student in NYU’s Department of Anthropology and College of Dentistry.

Specifically, the researchers found that calcium, magnesium, and are lower in females who have experienced reproduction. These changes are linked to giving birth itself and to lactation.

Nov 2, 2022

New technique helps identify genes related to aging

Posted by in categories: bioengineering, biological, chemistry, genetics, life extension

Researchers from North Carolina State University have developed a new method for determining which genes are relevant to the aging process. The work was done in an animal species widely used as a model for genetic and biological research, but the finding has broader applications for research into the genetics of aging.

“There are a lot of out there that we still don’t know what they do, particularly in regard to aging,” says Adriana San Miguel, corresponding author of a paper on the work and an assistant professor of chemical and biomolecular engineering at NC State.

That’s because this field faces a very specific technical challenge: by the time you know whether an organism is going to live for a long time, it’s old and no longer able to reproduce. But the techniques we use to study genes require us to work with animals that are capable of reproducing, so we can study the role of specific genes in subsequent generations.

Nov 2, 2022

New research rethinks the blood-tumor barrier and identifies novel path to brain cancer treatment

Posted by in categories: biotech/medical, neuroscience

In a new study, scientists have uncovered the mechanics of the blood-tumor barrier, one of the most significant obstacles to improving treatment efficacy and preventing the return of cancerous cells. The research team, led by Dr. Xi Huang, a Senior Scientist in Developmental & Stem Cell Biology program at The Hospital for Sick Children (SickKids), lays the foundation for more effectively treating medulloblastoma, the most common malignant pediatric brain tumor.

“Despite decades of research on brain cancer, the mechanisms that govern the formation and function of the blood-tumor barrier have remained poorly understood,” says Huang, who is also a Principal Investigator at the Arthur and Sonia Labatt Brain Tumor Research Center and Canada Research Chair in Cancer Biophysics. “Our discoveries represent a breakthrough in the understanding of how the blood-tumor barrier forms and works.”

In a paper published today in Neuron, the research team identifies a way to reduce the impact of the blood-tumor barrier on medulloblastoma treatment.

Nov 2, 2022

“Smart glass” windows could alter sunlight to replace Wi-Fi

Posted by in category: mobile phones

We’ve already seen systems that wirelessly transmit data via patterns of flickering light. A Saudi Arabian team has created a less energy-intensive alternative, that could use modulated sunlight in place of traditional Wi-Fi.

Currently in development at the King Abdullah University of Science and Technology (KAUST), the system utilizes “smart glass” elements known as Dual-cell Liquid Crystal Shutters (DLSs). These rapidly alter the polarity of sunlight passing through them, and could conceivably be used in the plate glass windows of large rooms such as offices.

The back-and-forth changes in polarity serve the same purpose as the 1s and 0s in binary code, and are reportedly not perceptible to the human eye … although tests have shown that they can be detected and decoded by smartphone cameras. By contrast, changes in the intensity of artificial light – utilized in some other proposed systems – can be visually perceived as an unpleasant flickering effect if the frequency of the changes is too low.

Nov 2, 2022

Replit’s Ghostwriter AI can explain programs to you—or help write them

Posted by in category: robotics/AI

Today, Replit announced Ghostwriter, an AI-powered programming assistant that can make suggestions to make coding easier. It works within Replit’s online development environment and resembles GitHub Copilot’s ability to recognize and compose code in various programming languages to accelerate the development process.

According to Replit, Ghostwriter works by using a large language model trained on millions of lines of publicly available code. This baked-in data allows Ghostwriter to make suggestions based on what you’ve already typed while programming in Replit’s IDE. When you see a suggestion you like, you can “autocomplete” the code by pressing the Tab key.

Nov 2, 2022

OpenAI’s Greg Brockman: The Future of LLMs, Foundation & Generative Models (DALL·E 2 & GPT-3)

Posted by in categories: business, robotics/AI

Greg Brockman, President and Co-Founder of @OpenAI, joins Alexandr Wang, CEO and Founder of Scale, to discuss the role of foundation models like GPT-3 and DALL·E 2 in research and in the enterprise. Foundation models make it possible to replace task-specific models with those that are generalized in nature and can be used for different tasks with minimal fine-tuning.

In January 2021, OpenAI introduced DALL·E, a text-to-image generation program. One year later, it introduced DALL·E 2, which generates more realistic, accurate, lower-latency images with four times greater resolution than its predecessor. At the same time, it released InstructGPT, a large language model (LLM) explicitly designed to follow instructions. InstructGPT makes it practical to leverage the OpenAI API to revise existing content, such as rewriting a paragraph of text or refactoring code.

Continue reading “OpenAI’s Greg Brockman: The Future of LLMs, Foundation & Generative Models (DALL·E 2 & GPT-3)” »