Comment

Comment by Dr. Krishna Kumari Challa on May 29, 2024 at 8:57am

IL-21 plays a crucial role in the formation of bone marrow plasma cells. Cells formed in IL-21-dependent follicular germinal centers have low CD19 expression, while those from IL-21-independent extrafollicular reactions have high CD19 levels.

Primary immune responses produce both CD19low and CD19high BMPCs, but secondary responses mainly create CD19high cells from reactivated memory B cells in extrafollicular sites. This finding is important for understanding how long-term immunity is maintained and how previous immune responses can impact the effectiveness of future vaccinations.

The rapid extrafollicular immune responses in tissues, like the bone marrow itself, are especially crucial for responding to emerging variants quickly. This research could help optimize vaccination strategies for better long-term protection.

Marta Ferreira-Gomes et al, Recruitment of plasma cells from IL-21-dependent and IL-21-independent immune reactions to the bone marrow, Nature Communications (2024). DOI: 10.1038/s41467-024-48570-0

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Part 2

Comment by Dr. Krishna Kumari Challa on May 29, 2024 at 8:56am

Study demonstrates how cytokines produce long lasting humoral immunity following vaccination

A new study has shed new light on how cytokines, in particular interleukin 21(IL-21), shape long lasting humoral immunity following vaccination.

Published in Nature Communications, the study  elucidates how various immune responses impact the recruitment and maintenance of memory plasma cells in the bone marrow. These cells are crucial for secreting protective antibodies and sustaining humoral immunity throughout a lifetime.

Researchers revealed the heterogeneity of human bone marrow plasma cells (BMPCs) and their origins from various immune reactions.

By analyzing single-cell transcriptomes from individuals vaccinated against SARS-CoV-2 and the triple vaccine against diphtheria, tetanus, and pertussis (DTaP), the team uncovered distinct pathways through which plasma cells are recruited to the bone marrow.

The study categorizes BMPCs into different "clans" based on their transcriptional profiles, presuming that these cells reflect the specific signals they received during their activation in the tissue.

Understanding the mechanisms behind the recruitment and maintenance of plasma cells in the bone marrow is crucial for improving vaccine strategies and developing therapies for immune-related diseases, including chronic inflammatory diseases such as systemic lupus erythematosus.

Part 1

Comment by Dr. Krishna Kumari Challa on May 29, 2024 at 8:44am

Light therapy increases brain connectivity following injury, study finds

Low-level light therapy appears to affect healing in the brains of people who suffered significant brain injuries, according to a study published in Radiology.

Lights of different wavelengths have been studied for years for their wound-healing properties. Researchers at Massachusetts General Hospital (MGH) conducted low-level light therapy on 38 patients who had suffered moderate traumatic brain injury, an injury to the head serious enough to alter cognition and/or be visible on a brain scan. Patients received light therapy within 72 hours of their injuries through a helmet that emits near-infrared light.

The skull is quite transparent to near-infrared light. Once you put the helmet on, your whole brain is bathing in this light. 

The researchers used an imaging technique called functional MRI to gauge the effects of the light therapy. They focused on the brain's resting-state functional connectivity, the communication between brain regions that occurs when a person is at rest and not engaged in a specific task. The researchers compared MRI results during three recovery phases: the acute phase of within one week after injury, the subacute phase of two to three weeks post-injury and the late-subacute phase of three months after injury.

Of the 38 patients in the trial, 21 did not receive light therapy while wearing the helmet. This was done to serve as a control to minimize bias due to patient characteristics and to avoid potential placebo effects.

Patients who received low-level light therapy showed a greater change in resting-state connectivity in seven brain region pairs during the acute-to-subacute recovery phase compared to the control participants.

There was increased connectivity in those receiving light treatment, primarily within the first two weeks. Researchers were unable to detect differences in connectivity between the two treatment groups long term, so although the treatment appears to increase the brain connectivity initially, its long-term effects are still to be determined. 

The precise mechanism of the light therapy's effects on the brain is also still to be determined. Previous research points to the alteration of an enzyme in the cell's mitochondria (often referred to as the "powerhouse" of a cell). 

This leads to more production of adenosine triphosphate, a molecule that stores and transfers energy in the cells. Light therapy has also been linked with blood vessel dilation and anti-inflammatory effects.

"There is still a lot of work to be done to understand the exact physiological mechanism behind these effects, though.

While connectivity increased for the light therapy-treated patients during the acute to subacute phases, there was no evidence of a difference in clinical outcomes between the treated and control participants. Additional studies with larger cohorts of patients and correlative imaging beyond three months may help determine the therapeutic role of light in traumatic brain injury. 

Effects of Low-Level Light Therapy on Resting-State Connectivity Following Moderate Traumatic Brain Injury: Secondary Analyses of a Double-blinded, Placebo-controlled Study, Radiology (2024).

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Comment by Dr. Krishna Kumari Challa on May 28, 2024 at 1:39pm

Comment by Dr. Krishna Kumari Challa on May 28, 2024 at 1:38pm

Debunking Fake Banana Hack Viral Videos

Debunking YouTube video myths and dis- and misinformation using bananas

Comment by Dr. Krishna Kumari Challa on May 28, 2024 at 7:08am

The aurorae at Earth and Jupiter are different. Yet, it is a big surprise that they can be explained by a unified framework.

By advancing our fundamental understanding of how planetary magnetic fields interact with the solar wind to drive auroral displays, this research has important practical applications for monitoring, predicting, and exploring the magnetic environments of the solar system.

This study also represents a significant milestone in understanding auroral patterns across planets that deepen our knowledge of diverse planetary space environments, paving the way for future research into the mesmerizing celestial light shows that continue to capture our imagination.

B. Zhang et al, A unified framework for global auroral morphologies of different planets, Nature Astronomy (2024). DOI: 10.1038/s41550-024-02270-3

Part 2

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Comment by Dr. Krishna Kumari Challa on May 28, 2024 at 7:07am

Scientists report unified framework for diverse aurorae across planets

The awe-inspiring aurorae seen on Earth, known as the Northern and Southern Lights, have been a source of fascination for centuries. Between May 10 and 12, 2024, the most powerful aurora event in 21 years reminded us of the stunning beauty of these celestial light shows.

Recently, space physicists have published a paper in Nature Astronomy that explores the fundamental laws governing the diverse aurorae observed across planets, such as Earth, Jupiter and Saturn.

This work provides new insights into the interactions between planetary magnetic fields and solar wind, updating the textbook picture of giant planetary magnetospheres. Their findings can improve space weather forecasting, guide future planetary exploration, and inspire further comparative studies of magnetospheric environments.

Earth, Saturn and Jupiter all generate their own dipole-like magnetic field, resulting in funnel-canopy-shaped magnetic geometry that leads the space's energetic electrons to precipitate into polar regions and cause polar auroral emissions.

Yet the three planets differ in many aspects, including their magnetic strength, rotating speed, solar wind condition, moon activities, etc. It is unclear how these different conditions are related to the different auroral structures that have been observed on those planets for decades.

Using three-dimensional magnetohydrodynamics calculations, which model the coupled dynamics of electrically conducting fluids and electromagnetic fields, the research team assessed the relative importance of these conditions in controlling the main auroral morphology of a planet.

Combining solar wind conditions and planetary rotation, they defined a new parameter that controls the main auroral structure, which for the first time, nicely explains the different auroral structures observed at Earth, Saturn and Jupiter.

Stellar winds' interaction with planetary magnetic fields is a fundamental process in the universe. The research can be applied to grasp the space environments of Uranus, Neptune, and even exoplanets.

This  study has revealed the complex interplay between solar wind and planetary rotation, providing a deeper understanding of aurorae across different planets. These findings will not only enhance our knowledge of the aurorae in our solar system but also potentially extend to the study of aurorae in exoplanetary systems.

Part 1

Comment by Dr. Krishna Kumari Challa on May 28, 2024 at 6:35am

A significant problem is that our solar system only contains about 100 Earths worth of solid material, so our advanced alien civilization would need to dismantle all the planets in 10,000 planetary systems and transport it to the star to build their Dyson sphere. To do it with the material available in a single system, each part of the megastructure could only be one meter thick.

This is assuming they use all the elements available in a planetary system. If they needed, say, lots of carbon to make their structures, then we're looking at dismantling millions of planetary systems to get hold of it. Now, I'm not saying a super-advanced alien civilization couldn't do this, but it is one hell of a job.

I'd also strongly suspect that by the time a civilization got to the point of having the ability to build a Dyson sphere, they'd have a better way of getting the power than using a star, if they really needed it (I have no idea how, but they are a super-advanced civilization).

Maybe I'm wrong, but it can't hurt to look.

Matías Suazo et al, Project Hephaistos – II. Dyson sphere candidates from Gaia DR3, 2MASS, and WISE, Monthly Notices of the Royal Astronomical Society (2024). DOI: 10.1093/mnras/stae1186

https://phys.org/news/2024-05-dyson-spheres-astronomers-potential-c...

Part 4

By  Simon Goodwin

Comment by Dr. Krishna Kumari Challa on May 28, 2024 at 6:33am

However, our global energy use has started to grow much more slowly over the past 50 years, and especially over the last decade. What's more, Dyson and Kardashev never specified what these vast levels of power would be used for, they just (fairly reasonably) assumed they'd be needed to do whatever it is that advanced alien civilizations do.

But, as we now look ahead to future technologies we see efficiency, miniaturization and nanotechnologies promise vastly lower power use (the performance per watt of pretty much all technologies is constantly improving).

A quick calculation reveals that, if we wanted to collect 10% of the sun's energy at the distance the Earth is from the sun, we'd need a surface area equal to 1 billion Earths. And if we had a super-advanced technology that could make the megastructure only 10km thick, that'd mean we'd need about a million Earths worth of material to build them from.
Part3

Comment by Dr. Krishna Kumari Challa on May 28, 2024 at 6:33am

Unfortunately, such light can also be a signature of a lot of other things, such as a disk of gas and dust, or disks of comets and other debris. But the seven promising candidates aren't obviously due to a disk, as they weren't good fits to disk models.

It is worth noting there is another signature of Dyson sphere: that visible light from the star dips as the megastructure passes in front of it. Such a signature has been found before. There was a lot of excitement about Tabby's star, or Kic 8462852, which showed many really unusual dips in its light that could be due to an alien megastructure.

It almost certainly isn't an alien megastructure. A variety of natural explanations have been proposed, such as clouds of comets passing through a dust cloud. But it is an odd observation. An obvious follow up on the seven candidates would be to look for this signature as well.
The case against Dyson spheres
Dyson spheres may well not even exist, however. I think they are unlikely to be there. That's not to say they couldn't exist, rather that any civilization capable of building them would probably not need to (unless it was some mega art project).

Dyson's reasoning for considering such megastructures assumed that advanced civilizations would have vast power requirements. Around the same time, astronomer Nikolai Kardashev proposed a scale on which to rate the advancement of civilizations, which was based almost entirely on their power consumption.

In the 1960s, this sort of made sense. Looking back over history, humanity had just kept exponentially increasing its power use as technology advanced and the number of people increased, so they just extrapolated this ever-expanding need into the future.

Part 2

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