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Mice that exercised soon after waking up had stronger and longer bones than those that exercised later in the day  

A rare sighting of a giant pangolin revives hopes for the species' survival in West Africa, despite threats from poaching and deforestation

I’m stealing ideas from an argument that has gone on between me and others in the last couple of days. The ideas come from readers and colleagues; only the data, rather scanty, is from me. .

Here’s what one reader wrote about the pro-Palestinian protestors who demand divestment from companies supplying weapons to Israel:

This brought up the question aboout why are they not protesting about Ukraine? That’s easy. The US is supporting and sending arms to Ukraine, so no. Which brought up the realization that these are the very same arms manufacturers producing arms for Israel that the university’s investment portfolio supports in some way. Do the SJP want the US to also stop aid to Ukraine? Because their goal is to stop arms production so that Israel cannot bomb Gaza. I realize that’s a rhetorical question, but brings up the thorny issue of calling for and actually boycotting industries that have multiple roles in world politics.

That raised the question that I spent about half an hour investigating. And, it turns out, the very same companies who make most of the weapons we send to Ukraine also make weapons we send to Israel. My cursory survey didn’t find one company that was an exception.

Here’s a list of seven companies I found that make weapons we send to Ukraine:

The long list of private US companies involved in supplying Israel with arms includes Lockheed Martin, Boeing; Northrop Grumman, General Dynamics, Ametek, UTC Aerospace, and Raytheon, according to CAAT.

It’s easier to find lists of companies that make arms that we send to Israel than to Ukraine, because nobody cares about Ukraine much any more, but I looked up each of those seven companies on the Internet (just Google the name of the company and add “Israel” or “arms for Israel”. Every one of them makes arms for both countries. That, of course, is not surprising given the concentration of effort in the defense industry, but it does raise the question: if we hurt Israel by divesting from US companies that supply it with weapons, do we not hurt Ukraine as well?

And that raises another question that’s above my pay grade: “How much does divestment from Israel involving U.S. weapons manufacturers really hurt Israel?” As I said, that’s a complex question, but it’s mostly theoretical because this divestment is not going to happen.

But one of my colleagues wrote me about the impracticality of divestment (all quotes are with permission):

I am sure that most of the arms manufacturers’ products are also used to fight other terrorists throughout the Middle East, North Africa, and Asia, as well as to defend US and European interests. There may be exceptions, but most big arms manufacturers sell to the US military as well. And their job is to fight terrorists and tyrants.

This is one reason that, if it worked (see below), divestment in arms manufacturers would be a bad idea.

However, it is my understanding that divestment would have no effect: if every university in the US sold all their shares to all arms manufacturers, someone else would buy them. And the value of the companies and their ability to make arms would be completely unaffected. (We have economists on this thread who will correct me if I’m wrong.)

Now let’s consider calls for divestment from Israel and Zionism. How would the decision be made and by whom? (Should Emam Abdelhadi be making decisions on investments? That seems like a bad idea.) What’s the litmus test? Should we stop investing in companies that are owned by Jews? Or just Zionists? And how do you tell? Is that the route we want to go down? That seems an awful lot like 1930s Germany to me.

And divestment violates the Kalven Principles.

So, IMO, divestment from arms manufacturers and Israel is anti-Semitic virtue signalling that violates Kalven and is either ineffective or would impact the West’s ability to wage war against terrorists and tyrants world wide.

The lessons, if all this is true: divestment from weapons companies is not an effective way to damage Israel, if that’s your goal; and it has bad effects on both the U.S. and Ukrainian military. Perhaps it’s better to just divest from Ben & Jerry’s.

As we discover more and more exoplanets – and the current total is in excess of 5,200 – we continue to try to learn more about them. Astrobiologists busy themselves analysing their atmospheres searching for anything that provides a sign of life. It is quite conceivable of course that the Universe is teeming with life based on very different chemistry to ours but we often look to life on Earth to know what to look for. On Earth for example, ozone forms through photolysis of molecular oxygen and is an indicator of life. Using the James Webb Space Telescope astronomers are searching stars in the habitable zone of their star for the presence of ozone and how it impacts their climate.

It’s tantalising that 425 of the exoplanets detected so far, exist in their stars habitable zone. It is in this region where the climate on the planet may well be suitable to sustain life. A significant subset of those planets are Earth-like in nature and will therefore have a fairly temperate climate. In addition, they all seem to orbit M-dwarf type stars which means they are likely to be impacted by tidal spin-synchronisation (due to the effects of the tides, one face of the planet may well be kept facing the star). One impact of this is the potential for large contrast in daytime and night-time irradiation which can drive strong convection on the day side of the planet.  

The strong convection can drive winds around the equatorial region that are persistently higher faster than the rotation of the planet. It can also create Rosby Waves which naturally occur in the Earth’s ocean and atmosphere – in any rotating fluids or gas. Together these can control the distribution of chemicals in the atmosphere, in particular ozone. 

In Earth’s atmosphere the presence of molecular oxygen is an indicator of life since it is produced largely from photosynthesis in plants. The molecular oxygen collides with nitrogen in the atmosphere to produce ozone so the presence of the latter is an indicator of biological processes. There is a chance though that the molecular oxygen in exoplanet atmospheres are the result of different ratios of near and far UV that can drive a non-biological build up. 

In a new piece of research reported in a paper by lead author Paolo De Luca and team, they report their findings having leveraged climate model simulations on Proxima Centauri b. The Earth-sized exoplanet orbits the red dwarf star Proxima Centauri, the closest star to our own at a distance of 4,.2 light years. 

An artist’s conception of a violent flare erupting from the red dwarf star Proxima Centauri. Such flares can obliterate atmospheres of nearby planets. Credit: NRAO/S. Dagnello.

They report that the analysis of atmospheres of tidally locked Earth-like exoplanets received a massive boost as a result of the development of the James Webb Telescope. The team reveal that their climate modelling (including the use of interactive ozone) globally increases temperature in the stratosphere. This in turn induces regional variations of surface temperature and also reduces the temperature contrast between day and night side. 

Whilst the team have not been able to identify life on exoplanets, that was not their intention. What they have achieved is the ability to understand the exoplanet atmospheres using the James Webb Space Telescope, some of the processes that lead to atmospheric ozone and the impacts on temperatures. 

Source : The impact of Ozone on Earth-like exoplanet climate dynamics: the case of Proxima Centauri b

The post What Impact Does Ozone Have on an Exoplanet? appeared first on Universe Today.

Strange solids called temporal metamaterials finally make it possible to investigate the controversial idea of quantum friction – and push special relativity to its limits

Researchers develop a vastly more productive way to convert carbon dioxide into useful materials and compounds.

In times of crisis, effective humanitarian aid depends largely on the fast and efficient allocation of resources and personnel. Accurate data about the locations and movements of affected people in these situations is essential for this. Researchers have now produced a framework to analyze and visualize population mobility data, which could help in such cases.

Researchers have developed an innovative positioning system that enhances the versatility and accuracy of drone-viewpoint mixed reality (MR) applications by aligning real and virtual world coordinates without predefined routes. By integrating visual positioning systems and natural feature-based tracking, this technology is expected to be applied to urban landscape simulation, maintenance, and inspection work.

Researchers have developed an innovative positioning system that enhances the versatility and accuracy of drone-viewpoint mixed reality (MR) applications by aligning real and virtual world coordinates without predefined routes. By integrating visual positioning systems and natural feature-based tracking, this technology is expected to be applied to urban landscape simulation, maintenance, and inspection work.

Biological processes depend on puzzle pieces coming together and interacting. Under specific conditions, these interactions can create something new without external input. This is called self-organization, as seen in a school of fish or a flock of birds. Interestingly, the mammalian embryo develops similarly. Scientists now introduce a mathematical framework that analyzes self-organization from a single cell to a multicellular organism.

A team of researchers has created a new way to visualize crystals by peering inside their structures, akin to having X-ray vision. Their new technique -- which they aptly named 'Crystal Clear' -- combines the use of transparent particles and microscopes with lasers that allow scientists to see each unit that makes up the crystal and to create dynamic three-dimensional models.

An international research team has sparked interest in the scientific community with results in quantum physics. In their current study, the researchers reinterpret the Higgs mechanism, which gives elementary particles mass and triggers phase transitions, using the concept of 'magnetic quivers.'

An international research team has sparked interest in the scientific community with results in quantum physics. In their current study, the researchers reinterpret the Higgs mechanism, which gives elementary particles mass and triggers phase transitions, using the concept of 'magnetic quivers.'

A fungus living in the sea can break down the plastic polyethylene, provided it has first been exposed to UV radiation from sunlight. Researchers expect that many more plastic degrading fungi are living in deeper parts of the ocean.

The intermediate range order of covalent glasses has been extensively studied in terms of the first sharp diffraction peak (FSDP), but the direct observation of the atomic density fluctuations that give rise to FSDP is still lacking. Addressing this gap, researchers employed a new energy-filtered angstrom-beam electron diffraction technique to provide the direct experimental observation for the origin of FSDP in silica glass, providing important insights into the atomic structure of glasses.

A team has scaled up the powerful brain-mapping tool BARseq. The technology is now capable of mapping millions of neurons throughout the brain. Identifying how neural connections are wired up over time is key to understanding the brain's perceptual abilities. It may also lead to better treatments for a variety of neurological conditions.

Team develops a flexible and stretchable device capable of omnidirectional color wavelength control.

Team develops a flexible and stretchable device capable of omnidirectional color wavelength control.

Scientists have employed artificial intelligence techniques to improve the design and production of nanofibers used in wearable nanofiber acoustic energy harvesters (NAEH). These acoustic devices capture sound energy from the environment and convert it into electrical energy, which can then be applied in useful devices, such as hearing aids.

Scientists have employed artificial intelligence techniques to improve the design and production of nanofibers used in wearable nanofiber acoustic energy harvesters (NAEH). These acoustic devices capture sound energy from the environment and convert it into electrical energy, which can then be applied in useful devices, such as hearing aids.