Menu

Blog

Page 5750

Dec 28, 2020

New chemistry for controlling the volume of liquid in volumetric additive manufacturing

Posted by in categories: chemistry, materials

A team of researchers affiliated with several institutions in Germany has developed new chemistry for improved control of the volume of liquid in volumetric additive manufacturing. In their paper published in the journal Nature, the group describes their process and how well it worked when tested.

Three-dimensional has made many headlines over the past decade as it has revolutionized the for a wide variety of products. Most 3D printing involves controlling gantries that work together to position a nozzle that applies different types of material to a base to build products. More recently, some new types of 3D printers have been developed for volumetric additive manufacturing, or VAM, that use light to induce polymerization in a liquid to create products. They work by building products a layer at a time. In this new effort, the researchers have improved the way that polymerization starts in VAM applications. By adding the ability to control the volume of liquid precursor involved in the initiation process, they were able to increase the resolution of VAM printing by 10 times. They call their newly improved process xolography because it involves the use of two crossing light beams to solidify a desired object.

The process begins with creating a rectangular sheet of light using a laser fired into a tub of liquid precursor. The laser excites the precursor molecules inside of the rectangle, preparing them for the second beam of light. The second laser is then directed into the rectangle as a preformed image slice. When the slice is projected into the rectangle, the excited precursor molecules solidify into a polymer, forming a solidified slice. The resin volume is then moved (the sheet remains fixed in place) so that the process can be repeated to create another slice. The overall process is repeated, creating more slices as it goes, until the desired shape is achieved.

Dec 28, 2020

The Brain Network Driving Changes in Consciousness

Posted by in category: neuroscience

Summary: A brain network consisting of the thalamus, anterior and posterior cingulate cortex, and angular gyri was implicated in the loss, and return, of consciousness under both anesthetic and natural sleep.

Source: SfN

The loss and return of consciousness is linked to the same network of brain regions for both sleep and anesthesia, according to new research published in Journal of Neuroscience.

Dec 28, 2020

The Rand Corp Has Just Published a Paper on Internet-Connected “Smart” Devices Which Track Body Functions

Posted by in categories: biotech/medical, health, internet, military

For those of us who don’t think that even our bowel movements will soon be inventoried, tracked and timestamped during every moment of existence, here is a just published white paper from the Rand Corporation, an influential think tank created in 1948 to offer research and analysis to the US military, which begs to differ.

The November 2020 whilte paper, published under the title “The Internet of Bodies,” focuses on the advantages and disadvantages, security and privacy risks, plus the ethical implications of what it calls a growing “Internet of Bodies (IoB).”

IoB tools are internet-connected “smart” devices increasingly available in the marketplace which promise to track and upload to the internet measurements related to individual heartbeat, blood pressure and other bodily functions in real time for purposes of health, exercise, security or other reasons.

Dec 28, 2020

Searching for invisible axion dark matter with a new multiple-cell cavity haloscope

Posted by in categories: cosmology, particle physics

Over the past few decades, many experimental physicists have been probing the existence of particles called axions, which would result from a specific mechanism that they think could explain the contradiction between theories and experiments describing a fundamental symmetry. This symmetry is associated with a matter-antimatter imbalance in the Universe, reflected in interactions between different particles.

If this mechanism took place in the early Universe, such a particle might have a very small mass and be ‘invisible. Subsequently, researchers proposed that the might also be a promising candidate for dark matter, an elusive, hypothetical type of matter that does not emit, reflect or absorb light.

While dark matter has not yet been experimentally observed, it is believed to make up 85% of universe’s mass. Detecting axions could have important implications for ongoing dark matter experiments, as it could enhance the present understanding of these elusive particles.

Dec 28, 2020

University of Colorado Boulder research team discovers compound that could aid in fight against antibiotic-resistant bacteria

Posted by in categories: biotech/medical, chemistry

CU Boulder researchers found a chemical compound that can break through cell membranes and potentially fight antibiotic-resistant bacteria.

Dec 28, 2020

Vermont Hospital confirmed the ransomware attack

Posted by in categories: biotech/medical, cybercrime/malcode, health

In October, threat actors hit the Wyckoff Heights Medical Center in Brooklyn and the University of Vermont Health Network. The cyber attack took place on October 28 and disrupted services at the UVM Medical Center and affiliated facilities.

A month later, the University of Vermont Medical Center was continuing to recover from the cyber attack that paralyzed the systems at the Burlington hospital.

In early December, Hospital CEO Dr. Stephen Leffler announced that the attack that took place in late October on the computer systems of the University of Vermont Medical Center is costing the hospital about $1.5 million a day in lost revenue and recovery costs.

Dec 28, 2020

Scientists turn CO2 into jet fuel

Posted by in categories: sustainability, transportation

Researchers may have found a way to reduce the environmental impact of air travel in situations when electric aircraft and alternative fuels aren’t practical. Wired reports that Oxford University scientists have successfully turned CO2 into jet fuel, raising the possibility of conventionally-powered aircraft with net zero emissions.

The technique effectively reverses the process of burning fuel by relying on the organic combustion method. The team heated a mix of citric acid, hydrogen and an iron-manganese-potassium catalyst to turn CO2 into a liquid fuel capable of powering jet aircraft.

Dec 28, 2020

Is Dark Energy Really “Repulsive Gravity”?

Posted by in category: cosmology

Circa 2012 o.o


“Repulsive gravity”—a powerful repulsion between matter and antimatter—could explain the force known as dark energy, a new theory claims.

Dec 28, 2020

Repulsive gravity as an alternative to dark energy (Part 2: In the quantum vacuum)

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

Circa 2012


(PhysOrg.com) — During the past few years, CERN physicist Dragan Hajdukovic has been investigating what he thinks may be a widely overlooked part of the cosmos: the quantum vacuum. He suggests that the quantum vacuum has a gravitational charge stemming from the gravitational repulsion of virtual particles and antiparticles. Previously, he has theoretically shown that this repulsive gravity can explain several observations, including effects usually attributed to dark matter. Additionally, this additional gravity suggests that we live in a cyclic Universe (with no Big Bang) and may provide insight into the nature of black holes and an estimate of the neutrino mass. In his most recent paper, published in Astrophysics and Space Science, he shows that the quantum vacuum could explain one more observation: the Universe’s accelerating expansion, without the need for dark energy.

“The was predicted theoretically more than 60 years ago,” Hajdukovic told PhysOrg.com. “Today, there is significant experimental evidence that the quantum vacuum exists. I have decided to combine one reality (the quantum vacuum) with one hypothesis (the negative gravitational charge of antiparticles) and to study the consequences. The hypothesis of the gravitational repulsion between matter and antimatter is older than half a century, but before me no one has used it in the combination with the quantum vacuum. … The results are surprising; there is potential to explain [the Universe’s accelerating expansion] in the framework of the quantum vacuum enriched with the gravitational repulsion between matter and antimatter.”

According to Hajdukovic, in the quantum vacuum arises from the gravitational between the positive gravitational charge of matter and the (hypothetical) negative gravitational charge of antimatter. While matter and antimatter are gravitationally self-attractive, they are mutually repulsive. (This part is similar to Massimo Villata’s theory from part 1, in which negatively charged antimatter exists in voids rather than in the quantum vacuum.) Although the quantum vacuum does not contain real matter and antimatter, short-lived and virtual antiparticles could momentarily appear and form pairs, becoming gravitational dipoles.

Dec 28, 2020

The unexpected benefits of virtual education

Posted by in categories: biotech/medical, education

It looks like virtual education(which is happening more now) is actually preparing students for the workplace of the future.


That said, there may be a silver lining to virtual classrooms and distance learning, which many universities and schools this academic year are defaulting to, in various degrees, due to the coronavirus. As students and teachers may have to compensate for logistic challenges, collaborating online might prepare high school students with the kind of organizational acumen, emotional intelligence and self-discipline needed for modern careers, particularly those that allow for the growing trend of working in remote, distributed teams. The sooner that students master those proficiencies, the better off they’ll be when they reach the job market.