Researchers measure electron emission to improve understanding of laser-based metal 3-D printing

Researchers measure electron emission to improve understanding of laser-based metal 3D printing
Researchers measured the emission of electrons from the surface of stainless steel under laser powder bed fusion (LPBF) conditions, demonstrating the potential for using thermionic emission signals to detect phenomena that can produce defects in parts and improve understanding of the LPBF process. The top image shows a multi-physics simulation of laser-induced melting of stainless steel, showing the electron emission signal primarily produced at the front of the surface depression. The bottom image depicts cross-sections of laser tracks produced in stainless steel. Monitoring of the thermionic emission can detect transition between conduction (left) and keyhole (right) mode welding regimes. Credit: Aiden Martin/LLNL

Lawrence Livermore National Laboratory (LLNL) researchers have taken a promising step in improving the reliability of laser-based metal 3-D printing techniques by measuring the emission of electrons from the surface of stainless steel during laser processing.


Researchers collected thermionic emission signals from 316L stainless steel under laser powder

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Understanding the utility of plasmas for medical applications — ScienceDaily

Plasma medicine is an emerging field, as plasmas show promise for use in a wide range of therapies from wound healing to cancer treatment. Plasma jets are the main plasma sources typically used in plasma-surface applications. Before applications can progress, however, a better understanding of how plasma jets modify the surfaces of biological tissue is required.

To help with this understanding, researchers from the Russian Academy of Sciences conducted computer simulations of the interaction between an atmospheric pressure plasma jet with a surface that has properties similar to blood serum. They present their analysis in the Journal of Applied Physics, from AIP Publishing.

“While using the plasma jets for the purpose of plasma medicine, it is important to know that the presence or absence of the treated surface in vicinity of a jet significantly influences jet parameters,” said Natalia Babaeva, one of the authors. “For example, the wounds with

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Understanding E-Resilience for Pandemic Recovery in Asia and the Pacific – World

The COVID-19 pandemic has accelerated the digital transformation and underscored its importance for mitigating the economic slowdown, sustaining wellbeing, and speeding up recovery. Governments, smart policymaking, as well as regional cooperation play an essential role in helping to both enable digital transformation to occur and in facilitating access to technology. In this regard, the Secretary-General’s Roadmap for Digital Cooperation, presented on June 11, 2020, comes at a critical inflection point for digital issues by outlining key areas for action to advance a safer, more equitable digital world.

The adoption of digital tools contributes substantially to the achievement of the SDGs. The development of the digital infrastructure to reduce the digital divide would first advance SDG 9 (Industry, Innovation, and Infrastructure). By providing access to more health-related information, ICT drives progress on SDG 3 (Good Health and Well-being). Digital tools can also democratize education and facilitate remote working, thereby promoting SDG

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Understanding traditional Chinese medicine can help protect species — ScienceDaily

Demystifying traditional Chinese medicine for conservationists could be the key to better protecting endangered species like pangolins, tigers and rhino, according to University of Queensland-led researchers.

UQ PhD candidate Hubert Cheung said efforts to shift entrenched values and beliefs about Chinese medicine are not achieving conservation gains in the short term.

He said a better understanding of traditional practices was critical for conservationists to form more effective strategies.

“The use of endangered species in traditional Chinese medicine threatens species’ survival and is a challenge for conservationists,” Mr Cheung said.

“Pushing messages of inefficacy, providing various forms of scientific evidence or promoting biomedical alternatives doesn’t seem to be drastically influencing decisions and behaviours.

“And, although many practices and treatments continue to be criticised for lacking scientific support, the World Health Organization approved the inclusion of traditional Chinese medicine in its global compendium of medical practices last year.

“The challenge now is

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Scientists call for decade of concerted effort to enhance understanding of the deep seas

Scientists call for decade of concerted effort to enhance understanding of the deep seas
A close-up image of a bamboo coral called Acanella arbuscula taken from ~1000m deep in the North East Atlantic Credit: NERC funded Deep Links Project (University of Plymouth, Oxford University, JNCC, BGS)

The deep seas—vast expanses of water and seabed hidden more than 200 meters below the ocean surface to depths up to 11,000 meters—are recognized globally as an important frontier of science and discovery.


But despite the fact they account for around 60% of Earth’s surface area, large areas remain completely unexplored, yet the habitats they support impact on the health of the entire planet.

Now an international team of scientists, spanning 45 institutions in 17 countries, has called for a dedicated decade-long program of research to greatly advance discovery in these remote regions.

The program—which scientists have named Challenger 150—will coincide with the United Nations Decade of Ocean Science for Sustainable Development, which runs from 2021-2030.

Challenger 150

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A better understanding of iceberg melting and lake ice formation could provide new indicators of climate change. — ScienceDaily

Eric Hester has spent the last three years chasing icebergs. A mathematics graduate student at the University of Sydney in Australia, Hester and researchers at Woods Hole Oceanographic Institution in Massachusetts are studying how the shape of an iceberg shapes the way it melts.

“Ice deforms as it melts,” said physical oceanographer Claudia Cenedese, who has worked with Hester on the project. “It makes these very weird shapes, especially on the bottom, like the way the wind shapes a mountain on a longer time scale.”

At the 73rd Annual Meeting of the American Physical Society’s Division of Fluid Dynamics, Hester presented results from his group’s experiments aimed at understanding how melting alters the face-changing boundary of a shrinking iceberg — and how those alterations in turn affect the melting.

The dynamics of iceberg melt is missing from most climate models, Cendese said. Including them could help with prediction: icebergs pump

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Understanding lung infections in patients with cystic fibrosis — ScienceDaily

For young people with cystic fibrosis, lung infection with Staphylococcus aureus, MRSA, is common and is treated with antibiotics in the hope that this will prevent a decline in lung function. However there has recently been debate over the role S. aureus plays in CF lung disease. Researchers from the University of Warwick have used a new model of CF lungs which could be used to make better decisions about future use of antibiotics.

S. aureus is commonly found on the skin of healthy people, it can cause lung infection and abscess, and is often present in the mucus and sputum of children with cystic fibrosis. When S. aureus — including the antibiotic-resistant form, MRSA — is found in people with CF, it is treated with antibiotics, but exactly how S. aureus affects the lungs in people with this condition is unknown.

Previous research models have often looked at

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Understanding astrophysics with laser-accelerated protons — ScienceDaily

Bringing huge amounts of protons up to speed in the shortest distance in fractions of a second — that’s what laser acceleration technology, greatly improved in recent years, can do. An international research team from the GSI Helmholtzzentrum für Schwerionenforschung and the Helmholtz Institute Jena, a branch of GSI, in collaboration with the Lawrence Livermore National Laboratory, USA, has succeeded in using protons accelerated with the GSI high-power laser PHELIX to split other nuclei and to analyze them. The results have now been published in the journal Nature Scientific Reports and could provide new insights into astrophysical processes.

For less than one picosecond (one trillionth of a second), the PHELIX laser shines its extremely intense light pulse onto a very thin gold foil. This is enough to eject about one trillion hydrogen nuclei (protons), which are only slightly attached to the gold, from the back-surface of the foil, and accelerate

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Virtual reality forests could help understanding of climate change

Virtual reality forests could help understanding of climate change
A Wisconsin type forest created in virtual reality to illustrate the effects of climate change scenarios on the trees and forest.  Credit: Alexander Klippel and Jiawei Huang, Penn State

The effects of climate change are sometimes difficult to grasp, but now a virtual reality forest, created by geographers, can let people walk through a simulated forest of today and see what various futures may hold for the trees.


“The main problem that needs to be addressed is that climate change is abstract,” said Alexander Klippel, professor of geography, Penn State. “Its meaning only unfolds in 10, 15 or 100 years. It is very hard for people to understand and plan and make decisions.”

The researchers combined information on forest composition with information on forest ecology to create a forest similar to those found in Wisconsin.

“As part of an NSF-funded CNH program grant with Erica Smithwick (E. Willard and Ruby

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Social media analytics now a valuable tool in understanding the thoughts and actions of the public during a pandemic — ScienceDaily

With 2020 hijacked by COVID-19, a team of QUT researchers in Brisbane, Australia, say social media analytics can capture the attitudes and perceptions of the public during a pandemic. They also suggest social media is now the best way to encourage people to follow measures and restrictions.

Led by Associate Professor Tan Yigitcanlar from QUT’s School of Built Environment, and in collaboration with researchers in Afghanistan, Iran and Italy, the researchers collected 96,666 geotagged tweets originating from Australia between 1 January and 4 May 2020, and analysed 35,969 of them after data cleaning to remove automated messages, irrelevant messages and web links.

The resultant paper — How can social media analytics assist authorities in pandemic-related policy decisions? Insights from Australian states and territories — has been published by Springer journal Health Information Science and Systems.

“From the Plague of Athens in 430 B.C., to the Black Death of the

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