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Jan 5, 2023

Amazon CEO says company will layoff more than 18,000 workers

Posted by in categories: economics, employment

Amazon is laying off 18,000 employees, the tech giant said Wednesday, representing the single largest number of jobs cut at a technology company since the industry began aggressively downsizing last year.

In a blog post, Amazon CEO Andy Jassy wrote that the staff reductions were set off by the uncertain economy and the company’s rapid hiring over the last several years.

The cuts will primarily hit the company’s corporate workforce and will not affect hourly warehouse workers. In November, Amazon had reportedly been planning to lay off around 10,000 employees but on Wednesday, Jassy pegged the number of jobs to be shed by the company to be higher than that, as he put it, “just over 18,000.”

Jan 5, 2023

The Eccentricities of J. Robert Oppenheimer

Posted by in categories: chemistry, cosmology, military, particle physics, quantum physics

The so-called “Father of the Atomic Bomb” J. Robert Oppenheimer was once described as “a genius of the nuclear age and also the walking, talking conscience of science and civilization”. Born at the outset of the 20th century, his early interests in chemistry and physics would in the 1920s bring him to Göttingen University, where he worked alongside his doctoral supervisor Max Born (1882−1970), close lifelong friend Paul Dirac (1902−84) and eventual adversary Werner Heisenberg (1901−76). This despite the fact that even as early as in his youth, Oppenheimer was singled out as both gifted and odd, at times even unstable. As a child he collected rocks, wrote poetry and studied French literature. Never weighing more than 130 pounds, throughout his life he was a “tall and thin chainsmoker” who once stated that he “needed physics more than friends” who at Cambridge University was nearly charged with attempted murder after leaving a poisoned apple on the desk of one of his tutors. Notoriously abrupt and impatient, at Göttingen his classmates once gave their professor Born an ultimatum: “either the ‘child prodigy’ is reigned in, or his fellow students will boycott the class”. Following the successful defense of his doctoral dissertation, the professor administering the examination, Nobel Laureate James Franck (1882−1964) reportedly left the room stating.

“I’m glad that’s over. He was at the point of questioning me”

From his time as student at Harvard, to becoming a postgraduate researcher in Cambridge and Göttingen, a professor at UC Berkeley, the scientific head of the Manhattan project and after the war, the Director of the Institute for Advanced Study, wherever Oppenheimer went he could hold his own with the greatest minds of his age. Max Born, Paul Dirac, John von Neumann, Niels Bohr, Albert Einstein, Kurt Gödel, Richard Feynman, they all admired “Oppie”. When he died in 1967, his published articles in physics totaled 73, ranging from topics in quantum field theory, particle physics, the theory of cosmic radiations to nuclear physics and cosmology. His funeral was attended by over 600 people, and included numerous associates from academia and research as well as government officials, heads of military, even the director of the New York City Ballet.

Jan 5, 2023

Shrinking hydrogels enlarge nanofabrication options

Posted by in categories: biological, nanotechnology

Researchers from Carnegie Mellon University and the Chinese University of Hong Kong have developed a strategy for creating ultrahigh-resolution, complex 3D nanostructures out of various materials.

Carnegie Mellon University’s Yongxin (Leon) Zhao and the Chinese University of Hong Kong’s Shih-Chi Chen have a big idea for manufacturing nanodevices.

Continue reading “Shrinking hydrogels enlarge nanofabrication options” »

Jan 5, 2023

A new chromium complex emits light in elusive NIR-II wavelength

Posted by in categories: biotech/medical, materials

Many applications, from fiber-optic telecommunications to biomedical imaging processes require substances that emit light in the near-infrared range (NIR). A research team in Switzerland has now developed the first chromium complex that emits light in the coveted, longer wavelength NIR-II range. In the journal Angewandte Chemie, the team has introduced the underlying concept: a drastic change in the electronic structure of the chromium caused by the specially tailored ligands that envelop it.

Many materials that emit NIR light are based on expensive or rare metal complexes. Cheaper alternatives that emit in the NIR-I range between 700 and 950 nm have been developed but NIR-II-emitting complexes of non– remain extremely rare. Luminescence in the NIR-II range (1000 to 1,700 nm) is, for example, particularly advantageous for in vivo imaging because this light penetrates very far into tissues.

The luminescence of complexes is based on the excitement of electrons, through the absorption of light, for example. When the excited electron drops back down to its , part of the energy is emitted as radiation. The wavelength of this radiation depends on the energetic differences between the electronic states. In complexes, these are significantly determined by the type and arrangement of the ligands bound to the metal.

Jan 5, 2023

More links aren’t necessarily better for hybrid nanomaterials

Posted by in categories: nanotechnology, solar power, sustainability

Chemists from Rice University and the University of Texas at Austin discovered more isn’t always better when it comes to packing charge-acceptor molecules on the surface of semiconducting nanocrystals.

The combination of organic and inorganic components in hybrid nanomaterials can be tailored to capture, detect, convert or control light in unique ways. Interest in these materials is high, and the pace of scientific publication about them has grown more than tenfold over the past 20 years. For example, they could potentially improve the efficiency of solar power systems by harvesting energy from wavelengths of sunlight—like infrared—that are missed by traditional photovoltaic solar panels.

To create the materials, chemists marry nanocrystals of light-capturing semiconductors with “charge acceptor” molecules that act as , attaching to the semiconductor’s surface and transporting electrons away from the nanocrystals.

Jan 5, 2023

Enabling nanoscale thermoelectrics with a novel organometallic molecular junction

Posted by in categories: energy, nanotechnology

The Seebeck effect is a thermoelectric phenomenon by which a voltage or current is generated when a temperature difference exists across a conductor. This effect is the basis of established and emerging thermoelectric applications alike, such as heat-to-electricity energy harvesters, sensing devices, and temperature control.

In line with the unrelenting demand for ever-smaller devices, scientists are looking for new ways to leverage the Seebeck effect at the nanoscale. One way to achieve this is by using molecular junctions, which are miniature devices consisting of two electrodes bridged by one or a few individual molecules. Depending on how sensitive these molecules are to temperature, it is possible to fine tune the thermoelectric properties of molecular junctions to match their intended application.

Thus far, most studies on molecular thermoelectrics have been limited to rather simple organic molecules. This has led to molecular junctions with a low Seebeck coefficient, which translates to poor temperature-to-voltage conversion and performance. There is therefore an ongoing challenge to design molecular junctions with better characteristics and, most importantly, a higher Seebeck coefficient.

Jan 5, 2023

What Luminar’s acquisition of startup Civil Maps means for its lidar future

Posted by in categories: economics, mapping, transportation

As lidar company Luminar pushed ahead to meet its goals for 2022 — milestones that included locking in new commercial contracts with unnamed automakers and shipping production-ready sensors to SAIC — it also snapped up a small HD mapping startup called Civil Maps.

The acquisition, which was disclosed Wednesday during Luminar founder and CEO Austin Russell’s presentation at CES 2023, is more than just a large publicly traded company taking advantage of a consolidating industry. Although the timing couldn’t have been better due to the current economic environment, according to Russell.

For Russell, the acquisition is part of Luminar’s longer term vision to be more than just a lidar supplier. Mapping, specifically the mapping tech that Civil Maps created, is foundational to that goal, Russell said.

Jan 5, 2023

2.6 billion-year-old ancestors of the CRISPR gene-editing tool are resurrected

Posted by in categories: bioengineering, biotech/medical, evolution, genetics

An international research group has for the first time reconstructed ancestors dating back 2.6 billion years of the well-known CRISPR-Cas system, and studied their evolution over time. The results suggest that the revitalized systems not only work, but are more versatile than current versions and could have revolutionary applications. Nature Microbiology has published the results of this research, which, in the opinion of the research team, “opens up new avenues for gene editing.”

The project, led by Ikerbasque research professor Rául Pérez-Jiménez of CIC nanoGUNE, involves teams from the Spanish National Research Council, the University of Alicante, the Rare Diseases Networking Biomedical Research Center (CIBERER), the Ramón y Cajal Hospital-IRYCIS and other national and international institutions.

The acronym CRISPR refers to the repeated sequences present in the DNA of bacteria and archaea (prokaryotic organisms). Among the repeats, these microorganisms harbor fragments of genetic material from viruses that infected their ancestors; that enables them to recognize a repeat infection and defend themselves by cutting the invaders’ DNA using Cas proteins associated with these repeats. It is a mechanism (CRISPR-Cas system) of antiviral defense. This ability to recognize DNA sequences is the basis of their usefulness, and they act as if they were molecular scissors. Nowadays CRISPR-Cas technology enables pieces of genetic material to be cut and pasted into any cell, so that it can be used to edit DNA.

Jan 5, 2023

Microsoft to challenge Google

Posted by in category: futurism

ChatGPT could make Bing search results more humanlike.

Jan 5, 2023

First look — Muse by Google AI/Research — Launched 2/Jan/2023 — (3B + 4.6B T5-XXL) — Google Muse

Posted by in categories: ethics, robotics/AI

The Memo: https://lifearchitect.ai/memo/

Demo site: https://muse-model.github.io/
Read the paper: https://arxiv.org/abs/2301.

Continue reading “First look — Muse by Google AI/Research — Launched 2/Jan/2023 — (3B + 4.6B T5-XXL) — Google Muse” »