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Meanwhile, in Dobrzyn, Hili is becoming demanding, as cats can be:

Hili: You have to renounce your immunity. A: What immunity is that? Hili: The one which protects you from accountability for an empty bowl.

Hili: Musisz zrzec się immunitetu.
Ja: Jakiego znowu immunitetu?
Hili: Chroniącego cię przed odpowiedzialnością za pustą miseczkę.

Supermassive Black Holes (SMBHs) are located in the centers of large galaxies like ours. When they’re actively feeding, they produce more light and are called active galactic nuclei (AGN). But their details are difficult to observe clearly because large clouds of gas block our view.

The JWST was built just for circumstances like these.

New research published in the Monthly Notices of the Royal Astronomical Society (MNRAS) presents JWST observations of an SMBH in a galaxy about 70 million light-years away. The telescope found polar dust surrounding the SMBH. It was outside the expected torus of dust that directly accretes onto the black hole that researchers call the accretion disk. The polar dust is heated, but rather than being heated by the radiation coming from the heated accretion disk, the gas is heated when by energetic shock waves that come from relativistic jets.

The research is titled “Dust beyond the torus: revealing the mid-infrared heart of local Seyfert ESO 428-G14 with JWST/MIRI.” The lead author is Houda Haidar, a PhD student in the School of Mathematics, Statistics, and Physics at Newcastle University in the UK. Houda and her co-researchers are members of GATOS, the Galactic Activity, Torus, and Outflow Survey. According to the GATOS website, GATOS is an international team using the JWST to “crack the enigma that is active galactic nuclei.”

“Having the opportunity to work with exclusive JWST data and access these stunning images before anyone else is beyond thrilling,” said Houda. “I feel incredibly lucky to be part of the GATOS team. Working closely with leading experts in the field is truly a privilege.”

This is the JWST’s first look at the galaxy in question, ESO 428-G14, but it’s not astronomers’ first look at it. They’ve been observing the galaxy—called a Seyfert galaxy because of its high luminosity—for decades. The astronomy community has used several telescopes to examine the galaxy, including ALMA and the Hubble, and that data forms part of this work.

The challenge in observing this AGN, and many others like it, is dust. The thick, extensive clouds of dust and gas that eventually feed the black hole block our view of it. The JWST’s job description is to pierce dust like this and get a clearer look into these obscured regions.

The JWST has four primary science themes, one of which is Galaxies Over Time. A combination of processes drives galaxy evolution, and active galactic nuclei are part of the picture.

Active galactic nuclei can emit relativistic jets of material from their poles that, in some cases, can extend hundreds of millions of light-years into space. ESO 428-G14 is no different; it emits radio jets from its poles. Astrophysicists know that gravitational and magnetic forces are behind these jets, but the exact mechanism behind them is unknown and is an active area of research.

The jets could be the key to understanding SMBHs, how they recycle material in galaxies, and the dust that accumulates around them in a torus. “For decades, the dusty torus has been held responsible for the dichotomy between type?1 and type?2 active galactic nuclei (AGN), forming the keystone of AGN unification,” the authors write.

The unified AGN model states that types 1 and 2 AGN are differentiated by their viewing angles rather than by any fundamental differences between the two. Type 1 is viewed more face-on relative to the dust torus, displays broad emission lines in its spectra, and has visible accretion disks. Type 2 is viewed more edge-on relative to the torus, has narrow emission lines, and has obscured accretion disks.

Some AGN have polar dust that’s separate from their torus dust. Many models predict that this dust is energized by the jets that come out of its poles. “However, little is known about its characteristics, spatial extent, or connection to the larger scale outflows,” the researchers write in their paper. This is “the first JWST/MIRI study aimed at imaging polar dust by zooming on to the centre of ESO 428-G14.”

The JWST found extended Mid-infrared emissions that extended to 650 light-years from the AGN. The structure of this polar dust is co-linear with a radio jet emitted by the AGN. But the dust is perpendicular to a molecular gas lane that’s feeding the AGN and obscuring it. This is important evidence for the presence of polar dust. “Its morphology bears a striking resemblance to that of gas ionized by the AGN,” the authors write.

This figure from the research illustrates some of the results. The left panel is a JWST/MIRI F1000W image showing the MIR structure of the circumnuclear disc along with the small-scale nuclear extensions. The right panel is a Hubble image of the same in optical light. The inset is the radio jet coming from the AGN. Image Credit: Haidar et al. 2024.

This brings us back to the ongoing debate about how AGN energize the gas and dust in their environment. What role do the jets play vs what role does electromagnetic radiation from the AGN play? One line of evidence shows that dust absorbs electromagnetic radiation emitted by the heated dust in the accretion disk.

However, the new JWST images show that much of the polar dust emission is extended and spread out along the jets’ paths. This clearly implies that the jets are responsible for heating and shaping the dust, and radiation from the AGN plays a lesser role. The accretion dust and the polar dust have different temperatures, and that provides clues about how different parts of the AGN are heated differently. Jet-induced shocks could be responsible for the heat differences between the polar dust and the accretion dust.

“There is a lot of debate as to how AGN transfer energy into their surroundings. We did not expect to see radio jets do this sort of damage. And yet here it is!” said Dr David Rosario, Senior Lecturer at Newcastle University and co-author of the study.

The post The JWST Reveals the Nature of Dust Around an Active Galactic Nuclei appeared first on Universe Today.

The covid-19 variant JN.1 may have been able to evade antibodies and spread globally due to one critical mutation to its spike protein

A new artificial intelligence model can predict how different proteins may bind to DNA.

Solid-state electrolytes have been explored for decades for use in energy storage systems and in the pursuit of solid-state batteries. These materials are safer alternatives to the traditional liquid electrolyte -- a solution that allows ions to move within the cell -- used in batteries today. However, new concepts are needed to push the performance of current solid polymer electrolytes to be viable for next generation materials.

Physicists have used Doppler-shifted nuclear resonant absorbers to form a nuclear frequency comb, enabling a quantum memory in the notoriously difficult X-ray range.

A research team has constructed an unprecedented chiral-structured interface in perovskite solar cells, which enhances the reliability and power conversion efficiency of this fast-advancing solar technology and accelerates its commercialization.

A research team reports a pioneering plasma-catalytic process for the hydrogenation of CO2 to methanol at room temperature and atmospheric pressure. This breakthrough addresses the limitations of traditional thermal catalysis, which often requires high temperatures and pressures, resulting in low CO2 conversion and methanol yield.

Most of us learned about butterfly metamorphosis as a kid -- a wriggly caterpillar molts its skin to form a tough chrysalis and emerges as a beautiful butterfly. But how exactly do chrysalises stay anchored as the butterfly brews within? Research shows that, despite their silks being weak and thin on their own, caterpillars can expertly spin them into chrysalis support structures resembling hook-and-loop fasteners and multi-strand safety tethers.

Microalgae such as the diatom Odontella aurita and the green alga Tetraselmis striata are especially suitable as 'biofactories' for the production of sustainable materials for 3D laser printing due to their high content in lipids and photoactive pigments. An international research team has succeeded for the first time in manufacturing inks for printing complex biocompatible 3D microstructures from the raw materials extracted from the microalgae.

Researchers invented a technique that uses a specialized light projector and a photosensitive chemical additive to imprint two- and three-dimensional images inside any polymer. The light-based engraving remains in the polymer until heat or light are applied, which erases the image and makes it ready to use again. The technology is intended for any situation where having detailed, precise visual data in a compact and easily customizable format could be critical, such as planning surgeries and developing architectural designs.

Researchers invented a technique that uses a specialized light projector and a photosensitive chemical additive to imprint two- and three-dimensional images inside any polymer. The light-based engraving remains in the polymer until heat or light are applied, which erases the image and makes it ready to use again. The technology is intended for any situation where having detailed, precise visual data in a compact and easily customizable format could be critical, such as planning surgeries and developing architectural designs.

Machine learning is a powerful tool in computational biology, enabling the analysis of a wide range of biomedical data such as genomic sequences and biological imaging. But when researchers use machine learning in computational biology, understanding model behavior remains crucial for uncovering the underlying biological mechanisms in health and disease. Researchers now propose guidelines that outline pitfalls and opportunities for using interpretable machine learning methods to tackle computational biology problems.

In the centre of a distant galaxy, a supermassive black hole has swallowed up a star 9 times the sun’s mass in the biggest and brightest such cosmic meal we’ve ever seen

A zigzag design can maximise how much heat walls radiate into space, while minimising heat absorption from the ground

Both Lin Yu-ting of Taiwan and Imane Khelif of Algeria earned medals in female boxing competition at the 2024 Olympics. This has caused a controversy because both boxers, according to reports, have some form of DSD – difference of sex development. This means they have been caught up in the culture war regarding trans athletes, even though neither of them is technically trans. What is the science here and how should sporting competitions like the Olympics deal with it?

Both female boxers have XY chromosomes (according to the IBA). For some people this means they are male, but as is often the case, it’s more complicated than that. Let’s quickly review some basic biology regarding biological sex to put this into perspective.

Male-Female develop does begin with sex chromosomes: XX for female and XY for male. Specific genes on the X and Y chromosomes affect sexual development, partly through production of sex hormones such as estrogen and testosterone. XX individuals develop ovaries and eggs, produce high estrogen and low testosterone, and develop anatomically along a typical female path with uterus, vagina, and with puberty, female secondary sexual characteristics. XY individuals develop gonads and sperm, make high testosterone, and develop along a typical male path with descended testes, penis and with puberty, male secondary sexual characteristics. All of this is part of biological sex. But also there is the potential for differences every step of the way. In addition, there are other chromosomal arrangements possible.  By some estimates about 1 in 300 people have some difference of sex development.

Yu-ting and Khelif are XY females. How does this happen? One possibility is that they have an incomplete Y chromosome, and may specifically lack the SRY gene which is necessary for male genital development. You can also have XY females who do not produce testosterone. Another possibility is complete androgen insensitivity syndrome (CAIS) in which XY individuals make testosterone but don’t have functioning receptors, so they develop as if they do not have testosterone (the default developmental pathway without testosterone is female). They typically have undescended tested, no uterus, but female external genitalia and female secondary sexual characteristics.

There are also XX females who are maculinized because they produce more androgens than is typical, such as in congenital adrenal hyperplasia. They may have ambiguous genitalia, but not always and may simply be identified female at birth. When they go through puberty, however, they can develop a deeper voice, become more hairy, and also develop more muscle mass and greater strength than a typical female.

The bottom line is that human biological sex is clearly not strictly binary. But the Olympics, like many sporting organizations, is strictly binary. How do we make these things work together? I think most people will agree we want sporting competitions to be fair and meaningful, but there can be disagreement on exactly what this means. Further, biological sex is just one of many parameters that can be affected by genetics and development that can impact sporting performance.

One question is – how much testing are we going to put athletes through to determine if they may have any genetic or developmental advantages related to sexual development? If we want at least a reasonably clear picture we would need to test for chromosomes, hormone levels, and receptor sensitivity. Such testing would be invasive and expensive, but nothing less would really show the complete picture. Also, the results would be along a spectrum, which means we would have to draw somewhat arbitrary dividing lines. Further still, who has the burden of proof to show that any particular biology has inherent advantages in any particular sport? And of course, the answer would differ for every sport – boxing and archery would not have the same biological advantages.

If we are going to open this can of worms, would it be consistent to also consider other biological factors. Heritage also impacts sports-relevant biological features. African Americans, for example, (both male and female) have higher average muscle mass and strength than Caucasians or Asians. The sex and race streams often cross, as AA women are more likely to be accused of being “too masculine”.

I am not proposing any specific answer here, just laying out the inherent complexity. There is not one right or wrong answer, just trade-offs. This is because there is an inherent disconnect between the binary world of sports and the non-binary world of human biological sex. Should we just exclude the estimated 26 million people in the world with DSD from competitive sports? Should we do very thorough biological assessments of athletes and divide them into leagues accordingly? Or do we do something in the middle, balancing various considerations to create an imperfect system that’s reasonably fair and functional?

I do think there is one thing we shouldn’t do – turn the whole thing into a culture war rife with pseudoscience and intolerance.

The post The Gender Boxing Hubub first appeared on NeuroLogica Blog.

A century ago, Albert Einstein suggested that the universe might contain ripples in space-time, known as gravitational waves – but then he changed his mind

A split in the southern vortex – not seen since 2002 – could lead to sudden warming of the Antarctic stratosphere and hotter weather in Australia and South America

Meanwhile, in Dobrzyn, Hili is schooled on the reality of life:

Hili: Why is the truth always left in the shadows? A: Because it demands concentration and fools are enchanted by the vulgar entertainment of liars.

 

 

Hili: Dlaczego prawda zostaje zawsze w cieniu?
Ja: Bo wymaga skupienia, a kłamcy urzekają głupców jarmarczną zabawą.

Two nankeen kestrels have been filmed flying in a wind tunnel to learn how the raptors keep their heads in a fixed position under turbulent conditions