Major 'Population Correction' Coming For Humanity, Scientist thinks

A little over two centuries ago, in the year 1800, roughly a billion people called Earth home.

Just a century later, it had grown by another 600 million.

Today, there are around 8 billion people on the planet.

That sort of growth is unsustainable for our ecosphere, risking a 'population correction' that according to a new study could occur before the century is out. The prediction is the work of population ecologist William Rees from the University of British Columbia in Canada. He argues that we're using up Earth's resources at an unsustainable rate, and that our natural tendencies as humans make it difficult for us to correct this "advanced ecological overshoot".

The result could be some kind of civilizational collapse that 'corrects' the world's population, Rees says – one that could happen before the end of the century in a worst case scenario. Only the richest and most resilient societies would be left.

"Homo sapiens has evolved to reproduce exponentially, expand geographically, and consume all available resources," Rees writes in his published paper.
For most of humanity's evolutionary history, such expansionist tendencies have been countered by negative feedback. However, the scientific revolution and the use of fossil fuels reduced many forms of negative feedback, enabling us to realize our full potential for exponential growth."

Rees points out our dominance over the planet has made us forget that we are still governed by natural selection. What's more, our natural inclination towards short-term thinking, which served us exceedingly well in our evolutionary past, continues to compel us to take as much as we can possibly get when it's available.
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This has fueled the excessive consumption and pollution that a portion of the current world population is now responsible for, which is set to increase as financial security and population sizes increase, Rees argues. A changing climate is evidence of the strain the planet is already under but it's only a tiny fraction of the overall problem of overshoot, Rees argues. As Rees points out, as we continue to use an abundance of fossil fuels we're simultaneously ignoring the other symptoms of overshoot too. From our consumption of biomass to the disruption of planetary nutrient cycles, these interlinked problems are all propelling Earth's sixth mass extinction and risking a chaotic break-down of our planet's essential life-support systems.

What's more, our proposed solutions, such as switching to renewables don't actually address the problem of exponential population growth and in fact further contribute to the excess consumption that goes along with it. The question is whether improvements in technology – in everything from combating climate change to increasing food production – are capable of keeping pace with the growing demands our consumption places on the planet. If innovation can't provide solutions, food shortages, habitat instability, war, and disease may well start to make an impact in population numbers, this study predicts. "While no major symptom of overshoot can be adequately addressed in isolation from the others, addressing overshoot directly would reduce all important symptoms simultaneously," Rees explains. Another point that Rees makes – and he's not the first to do so – is that we need to be much more aware of the peril that we're in, and should be working out ways to get a better balance between our give-and-take relationship with the planet. "In the best of all possible worlds, the whole transition might actually be managed in ways that prevent unnecessary suffering of millions (billions?) of people, but this is not happening – and cannot happen – in a world blind to its own predicament," writes Rees.

https://www.mdpi.com/2673-4060/4/3/32

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WHO’s first traditional-medicine summit
Yesterday kicked off the first-ever World Health Organization (WHO) summit dedicated to traditional medicine, including disciplines as wide-ranging as Ayurveda, yoga, homeopathy and complementary therapies. Billions of people use traditional healing systems, so some researchers have called for more rigorous science, such as randomized control trials or systematic reviews, to understand these practices and to ensure the safety of products such as herbal medicines. But some scientists worry that the summit will be insufficiently critical, resulting in “the often-before voiced platitudes and wishful thinking”, according to complementary-medicine researcher Edzard Ernst.

https://www.nature.com/articles/d41586-023-02636-z?utm_source=Natur...

Using magnetic rust nanoparticles to clean water

Scientists find way to wipe a cell's memory to better reprogram it as a stem cell

In a study published in Nature,  scientists have resolved a long-standing problem in regenerative medicine. They developed a new method to reprogram human cells to better mimic embryonic stem cells, with significant implications for biomedical and therapeutic uses.

In a revolutionary advance in the mid-2000s, it was discovered that the non-reproductive adult cells of the body, called somatic cells, could be artificially reprogrammed into a state that resembles embryonic stem (ES) cells which have the capacity to then generate any cell of the body.

The ability to artificially reprogram human somatic cells, such as skin cells, into these so-called induced pluripotent stem (iPS) cells provided a way to make an essentially unlimited supply of ES-like cells, with widespread applications in disease modeling, drug screening and cell-based therapies.

However, a persistent problem with the conventional reprograming process is that iPS cells can retain an epigenetic memory of their original somatic state, as well as other epigenetic abnormalities. This can create functional differences between the iPS cells and the ES cells they're supposed to imitate, and specialized cells subsequently derived from them, which limits their use.

Researchers have now developed a new method, called transient-naïve-treatment (TNT) reprogramming, that mimics the reset of a cell's epigenome that happens in very early embryonic development. This significantly reduces the differences between iPS cells and ES cells and maximizes the effectiveness of how human iPS cells can be applied. 

By studying how the somatic cell epigenome changed throughout the reprogramming process, they pinpointed when epigenetic aberrations emerged, and introduced a new epigenome reset step to avoid them and erase the memory.

TNT reprogramming will establish a new benchmark for cell therapies and biomedical research, and substantially advance their progress.

https://www.nature.com/articles/s41586-023-06424-7?utm_medium=affil...

Why Does It Take a While For a Tan to Show Up? Scientists Have Finally Worked It Out

Your skin's response to Sun exposure may seem delayed, but there's a good reason for it, scientists have found.

Through experiments on both human and mouse skin, researchers  have discovered that the development of a tan only occurs after the skin has taken care of emergency DNA repair.

We have two mechanisms designed to protect the skin from exposure to dangerous UV radiation. 

The first mechanism repairs the DNA in the skin cells damaged by the radiation, while the second mechanism involves increased production of melanin, which darkens the skin in order to protect it from future exposure to radiation.

The delay in tanning is a result of resource prioritization. Basically, all of the cell's resources mobilize to repair radiation damage as quickly as possible. It's only once that task is complete that the cell can allocate resources to the production of melanin.

To test this hypothesis, the researchers first exposed human skin, obtained from consenting surgery patients and cultured in petri dishes, to UVB radiation. This was so that they could study the activity in the cell in response to radiation damage. They confirmed that a protein kinase called ATM, activated by DNA damage and critical to cell repair, springs into action shortly after exposure to UVB radiation. That's interesting, but the team needed more information. So, the follow-up step was to trigger the activation of ATM in the absence of UVB exposure and observe the results. This phase of the experiment was conducted on mouse models, and more human skin samples in petri dishes. In both mouse and human skin, a tan developed after an interval, even in the absence of harmful radiation. A close inspection of the cellular processes involved showed that the activation of ATM blocks the activation of the MITF protein responsible for increasing melanin production, so that DNA repair can take precedence.

The genetic information must be protected from mutations, so this repair mechanism takes precedence inside the cell during exposure to ultraviolet radiation from the sun.

The team suspects that DNA repair may even harness some of the components of the pigmentation mechanism in order to maximize the chances of cell survival, and minimize the chances of mutation. The discovery, the team says, could be used to help study, understand, prevent, and treat the effects of skin radiation damage.

https://www.sciencedirect.com/science/article/abs/pii/S0022202X2302...

Parasites Are Actually Vital For Some Species' Survival, Study Shows

Parasites are understandably unpopular. Some cause horrible illnesses in their hosts, and even the less dangerous ones are often creepy or gross.

While they can be monsters, parasites aren't all bad. Many organisms benefit from species that survive by sucking the very life from others. Even their hosts might get a kickback or two.
Now a new study suggests some species can only survive in certain habitats if parasites are there, too.

Parasites come in many shapes and sizes, from viruses and amoebae to plants like mistletoe and animals like nematodes or mosquitoes. They all use a host for resources, which they typically harm but don't kill. As the late entomologist E.O. Wilson put it, parasites are "predators that eat prey in units of less than one."

Similar to the way predators can help regulate their overall ecosystem, parasites often provide overlooked ecological services that are only obvious in their absence.
the horrors of individual parasitic infections belie the surprising value these creatures offer for their broader community.

"Parasites and pathogens are an integral part of any ecosystem. Despite their bad reputation, parasites play a key role in shaping population dynamics, community structure, and biodiversity, thanks to their influence on the balance between the species in that ecosystem
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In a new study, researchers focused on how parasites influence populations of tiny crustaceans commonly called "water fleas," from the genus Daphnia.
Daphnia grow up to 5 millimeters long, inhabiting various freshwater habitats where they feed on single-celled algae, bacteria, and protists. In turn, they serve as a food source for other larger aquatic species, like fish, tadpoles, and insects.

Using two Daphnia species with differing levels of parasite resistance, the researchers tested how the presence of parasites affected an ecological phenomenon known as the competitive exclusion principle, or Gause's law, among the water fleas.

Biodiversity is a key feature of healthy ecosystems, Orlansky and Ben-Ami note, and related species can share space if their relationships with predators and natural resources are different enough.

According to Gause's law, however, two species with identical niches in the same habitat can't coexist indefinitely at constant levels. If they're too similar, even a small advantage can help one species dominate, leaving others to eventually die out or seek a different niche.
The Daphnia species in this study are adapted to small rock pools – relatively enclosed habitats where many aquatic lifeforms can't migrate or come and go on their own.
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This tightens competition among the creatures living there, the researchers explain, making rivalry a big factor in determining the pools' biodiversity. With so few other niches to fall back on, any species that can't compete will struggle to survive.

Most animals serve as hosts or carriers for parasites of some kind, and water fleas are no exception. It's rare to find a species with nearly total parasite resistance, yet the study did include one Daphnia species with an almost supernatural ability to withstand parasites.

"In the population of water fleas in Israel, we found one species called Daphnia similis, whose nickname in the laboratory is 'Super Daphnia' due to its almost complete resistance to parasites.
Nevertheless, this 'Super Daphnia' does not become the dominant Daphnia species in ponds.
The most common species is actually Daphnia magna, which is highly vulnerable to a wide variety of parasites."

To figure out why, the researchers simulated an ecosystem in the lab, placing the two Daphnia species together in habitats either with or without parasites.

In a habitat free of parasites, not only did the parasite-sensitive D. magna outcompete its parasite-resistant relative, the study found, but it was the only Daphnia left standing.
Things played out differently in habitats with parasites, however, where D. magna proved less dominant and Super Daphnia managed to establish a population and coexist with D. magna – thanks to a little help from parasites.

"The results of these experiments emphasize the important role of parasites in shaping biodiversity, as the parasites can mediate competition between Daphnia species.
Although Super Daphnia excels at resisting parasites, its overall competitive ability still doesn't match that of D. magna and without parasites it "would probably become extinct when it shares the same habitat."
This work shows that coexistence of these two Daphnia species is only possible through the mediation of a parasite..
By learning details like this about the ecological sway of parasites, the researchers say, we may gain new insights to help us fend off invasive species or better protect endangered wildlife.

https://www.frontiersin.org/articles/10.3389/fmicb.2023.1135252/full

Part 3

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India Is About to Attempt Its First Ever Moon Landing Can anybody else ever feel the same way Neil Armstrong felt when he first stepped on the moon? Or how Watson, Rosalind Franklin and Crick felt when they first discovered the double helix of DNA? Their experiences are mind blowing and no amount of money can buy you that thrill. Can anybody feel the same way scientists feel when they discover/invent something for the first time and report it to the world? NO. Nothing in this world compares to it. Experience at least some of it when the Indian Space Research Organisation (ISRO) mission Chandrayaan-3 will deploy its lander and rover to the surface of the Moon on 23rd Aug. Chandrayaan-3, is all set to make a soft and successful landing on the south polar region of the Moon around 6.04pm today, August 23. In case of 'unfavourable conditions' the landing may be postponed to August 27. But that is not on the cards right now. Viewers can watch the live landing on the ISRO website, its YouTube channel, Facebook, and public broadcaster DD National TV starting at 5:27 PM (IST) on August 23 (today). Every success by a space agency means more free-to-use data for both the scientific community and the public. Come join us on this epic journey.

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Gravitational Waves: Ripples In Space-Time

 Quantum entanglement of photons captured in real-time

Researchers  recently demonstrated a novel technique that allows the visualization of the wave function of two entangled photons, the elementary particles that constitute light, in real-time.

Using the analogy of a pair of shoes, the concept of entanglement can be likened to selecting a shoe at random. The moment you identify one shoe, the nature of the other (whether it is the left or right shoe) is instantly discerned, regardless of its location in the universe. However, the intriguing factor is the inherent uncertainty associated with the identification process until the exact moment of observation.

The wave function, a central tenet in quantum mechanics, provides a comprehensive understanding of a particle's quantum state.  For instance, in the shoe example, the "wave function" of the shoe could carry information such as left or right, the size, the color, and so on.

More precisely, the wave function enables quantum scientists to predict the probable outcomes of various measurements on a quantum entity, e.g. position, velocity, etc.

This predictive capability is invaluable, especially in the rapidly progressing field of quantum technology, where knowing a quantum state which is generated or input in a quantum computer will allow to test the computer itself. Moreover, quantum states used in quantum computing are extremely complex, involving many entities that may exhibit strong non-local correlations (entanglement).

Knowing the wave function of such a quantum system is a challenging task—this is also known as quantum state tomography or quantum tomography in short. With the standard approaches (based on the so-called projective operations), a full tomography requires large number of measurements that rapidly increases with the system's complexity (dimensionality).

Previous experiments conducted with this approach by the research group showed that characterizing or measuring the high-dimensional quantum state of two entangled photons can take hours or even days. Moreover, the result's quality is highly sensitive to noise and depends on the complexity of the experimental setup.

Part 1

The projective measurement approach to quantum tomography can be thought of as looking at the shadows of a high-dimensional object projected on different walls from independent directions. All a researcher can see is the shadows, and from them, they can infer the shape (state) of the full object. For instance, in CT scan (computed tomography scan), the information of a 3D object can thus be reconstructed from a set of 2D images.

In classical optics, however, there is another way to reconstruct a 3D object. This is called digital holography, and is based on recording a single image, called interferogram, obtained by interfering the light scattered by the object with a reference light.

Researchers now  extended this concept to the case of two photons.

Reconstructing a biphoton state requires superimposing it with a presumably well-known quantum state, and then analyzing the spatial distribution of the positions where two photons arrive simultaneously. Imaging the simultaneous arrival of two photons is known as a coincidence image. These photons may come from the reference source or the unknown source. Quantum mechanics states that the source of the photons cannot be identified. This results in an interference pattern that can be used to reconstruct the unknown wave function. This experiment was made possible by an advanced camera that records events with nanosecond resolution on each pixel.

This method is exponentially faster than previous techniques, requiring only minutes or seconds instead of days. Importantly, the detection time is not influenced by the system's complexity—a solution to the long-standing scalability challenge in projective tomography.

The impact of this research goes beyond just the academic community. It has the potential to accelerate quantum technology advancements, such as improving quantum state characterization, quantum communication, and developing new quantum imaging techniques.

Danilo Zia et al, Interferometric imaging of amplitude and phase of spatial biphoton states, Nature Photonics (2023). DOI: 10.1038/s41566-023-01272-3

Part 2

Bilinguals may have a memory advantage

In any communication, we generate myriad predictions regarding what we are about to hear. To begin with—when we only have one or two letters to go on—the pool of potential candidate words is massive. The more letters we guess correctly, the more the pool of candidate words narrows down, until our brain clicks and we find the right word.

In natural communication, we rarely wait to hear the entire word before we begin to plan what to say back. As soon as we hear the first sounds of a word, our brain uses this information, and together with other clues—such as frequency, context and experience—fills in the blanks, cutting down from a vast list of potential candidate words to predict the target word. But what if you are a bilingual with languages that have similar sounding words? Well, then, the list of candidate words is much larger. This may sound negative—making it more difficult to predict words. But a new study, published in Science Advances, has revealed that this may actually give bilinguals an advantage when it comes to memory.

The languages of a bilingual are interconnected. The same neural apparatus that processes our first language also processes our second language. So it is easy to see why, upon hearing the first sounds of a word, potential candidate words are activated, not only from one language, but from the other one as well.

For instance, upon hearing the sounds "k" and "l", a Spanish-English bilingual will automatically activate both the words "clock" and "clavo" (nail in Spanish). This means the bilingual has a tougher cutting down job to do in order to settle on the correct word, simply because there is more to cut down to get to the target. It is not surprising then that bilinguals usually take more time to retrieve or recognize words in psychological and linguistic experiments.

The findings showed that recognition memory for objects with many competitors (such as beaker, beetle, speaker) was enhanced relative to items with low competitors (such as carriage) in both monolinguals and bilinguals. In addition, bilinguals showed the effect for cross-language competitors as well (for example clock, clavo)—giving an overall memory advantage.

Interestingly, second language proficiency played a crucial role. The memory advantage was most profound in bilinguals with high second language proficiency than in bilinguals with low second language proficiency and monolinguals. Clearly, to play bilingual hangman efficiently, you need to develop high proficiency in the second language, so that its words become competitors alongside those of the first language.

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The eye tracking data confirmed that items with more competitors were looked at the longest, which led to the memory advantage for those items later on. These findings show that the bilingual cognitive system is highly interactive and can impact other cognitive components such as recognition memory.

Other studies also show enhanced memory processing in bilinguals relative to monolinguals in categorization tasks that require suppressing distracting information. This could certainly indicate that bilinguals are more efficient at multi-tasking and more able to focus on the task at hand, especially when the task requires ignoring irrelevant information (think trying to work in a noisy café).

The picture that emerges is one where bilingualism is a cognitive tool that enhances basic cognitive functions, such as memory and categorization. Bilingual hangman is a tougher game, but one that, ultimately, pays off.

Now  what about multilinguals like me?

Matias Fernandez-Duque et al, Speakers of different languages remember visual scenes differently, Science Advances (2023). DOI: 10.1126/sciadv.adh0064

Part 2

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Silica particles found in food and makeup could be chemically reactive, study finds

New research has revealed that the mineral silica, a common food additive and popular cosmetics ingredient, is not a chemically inert substance, as has long been supposed.

As described in a new study, researchers placed commercially available silica particles in a water solution with biomolecules containing compounds called thiols. These thiol-containing biomolecules are widespread in nature and in the human body, for instance, in the form of glutathione, a key antioxidant found in most cells. When exposed to silica, the thiol biomolecules underwent redox chemical reactions. These reactions, in which electrons are lost, could degrade or alter the molecules' function, potentially posing health risks. For instance, low levels of glutathione can lead to increased oxidative stress in the body that can damage all manner of cellular components, from membranes to DNA.

The findings highlight the need for further research into the reactivity of silica, especially given its extensive usage in everyday products.

Silica—another name for compounds of silicon and oxygen—is a colorless, odorless, tasteless material. While silica occurs naturally in foods including leafy greens, manufacturers often add tiny, sand-like particles of silica as an anticaking agent to soups and coffee creamers, for instance. 

For cosmetics, including skin care products, silica serves as a bulking or absorbing agent, or as an abrasive in scrubs. In health care, silica particles have also found significant use in the delivery of drugs and for medical imaging purposes. For those applications, silica particles are manufactured to have tiny holes, or pores, into which pharmaceuticals and other substances can be slotted.

For the study, the  researchers purchased commercially available, pure silica particles, sold as a dry powder.

Yangjie Li et al, Silica particles convert thiol-containing molecules to disulfides, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2304735120

Teens Who Smoke Show Reduced Brain Matter, Scientists Discover

Neurological imaging reveals people more inclined to begin smoking as teenagers tend to have reduced gray matter in two important brain regions, indicating they may play a significant role in inhibition and addiction.

An international team of researchers compared MRI brain scans from over 800 people, collected from the UK, Germany, France and Ireland across different time points. These volunteers also answered questionnaires on personality traits. The researchers then compared those who began smoking by age 14 with non-smokers and repeated this again with the same patients at ages 19 and 23. The images revealed those who took up smoking from the age of 14 had comparitively less gray matter in the left ventromedial prefrontal cortex; a part of the brain involved in emotional regulation, decision-making, and self-control. Scans taken five years later revealed the opposite part of this same brain region (on the right) was also reduced in the smoker group compared to non-smokers. This side of the ventromedial prefrontal cortex has also been linked to pleasure. The ventromedial prefrontal cortex is a key region for dopamine, the brain's pleasure chemical. As well as a role in rewarding experiences, dopamine has long been believed to affect self-control.

https://www.nature.com/articles/s41467-023-40079-2

Caffeine in Your Blood May Affect Body Fat And Diabetes Risk, Study Finds

The levels of caffeine in your blood could affect the amount of body fat you carry, a factor that in turn could determine your risk of developing type 2 diabetes and cardiovascular diseases. Those are the findings of a recent study that used genetic markers to establish a more definitive link between caffeine levels, BMI, and type 2 diabetes risk. The researchers suggest that calorie-free caffeinated drinks could be explored as a potential means of helping reduce body fat levels. Genetically predicted higher plasma caffeine concentrations were associated with lower BMI and whole body fat mass. Furthermore, genetically predicted higher plasma caffeine concentrations were associated with a lower risk of type 2 diabetes. Approximately half of the effect of caffeine on type 2 diabetes liability was estimated to be mediated through BMI reduction. In general, those with variations affecting the genes – namely CYP1A2 and a gene that regulates it, called AHR – tend to break caffeine down more slowly, allowing it to remain in the blood longer. Yet they also tend to drink less caffeine in general.

https://bmjmedicine.bmj.com/content/2/1/e000335

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First complete sequence of a human Y chromosome

For decades, the Y chromosome—one of the two human sex chromosomes—has been notoriously challenging for the genomics community to sequence due to the complexity of its structure.

Now, this elusive area of the genome has been fully sequenced, a feat that finally completes the set of end-to-end human chromosomes and adds 30 million new bases to the human genome reference, mostly from challenging-to-sequence satellite DNA. These bases reveal 41 additional protein-coding genes, and provide crucial insight for those studying important questions related to reproduction, evolution, and population change.

The complete, annotated Y chromosome reference is available for use on the UCSC Genome Browser and can be accessed via Github.

When scientists and clinicians study an individual's genome, they compare the individuals' DNA to that of a standard reference to determine where there is variation. Until now, the Y chromosome portion of the human genome has contained large gaps which made it difficult to understand variation and associated disease.

The structure of the Y chromosome has been challenging to decode because some of the DNA is organized in palindromes—long sequences that are the same forward and backward—spanning up to more than a million base pairs. Moreover, a very large part of the Y chromosome that was missing from the previous version of the Y reference is satellite DNA—large, highly repetitive regions of non-protein-coding DNA. On the Y chromosome, two satellites are interlinked with each other, further complicating the sequencing process.

The researchers were able to achieve a gapless read of the Y chromosome due to advances in long-read sequencing technology and new, innovative computational assembly methods that could deal with the repetitive sequences and transform the raw data from sequencing into a usable resource.

These new method assemblies allowed the team to tackle some of the particularly challenging aspects of the Y chromosome, such as pinpointing precisely where an inversion occurs in a palindromic sequence—a technique that can be used to find other inversions. The methods established in the paper will allow scientists to complete more end-to-end reads of human Y chromosomes to get a better understanding of how this genetic material affects the diverse human population.

The complete Y chromosome reference will allow scientists to better study a myriad of features about this part of the human genome in a way that has never before been possible.

The complete sequence of a human Y chromosome, Nature (2023). DOI: 10.1038/s41586-023-06457-y. www.nature.com/articles/s41586-023-06425-6. On bioRxiv: DOI: 10.1101/2022.12.01.518724

How a cup of water can unlock the secrets of our universe

Researchers have made a discovery that could change our understanding of the universe. In their study published in Science Advances, they reveal, for the first time, that there is a range in which fundamental constants can vary, allowing for the viscosity needed for life processes to occur within and between living cells. This is an important piece of the puzzle in determining where these constants come from and how they impact life as we know it.

In 2020, the same scientists found that the viscosity  of liquids is determined by fundamental physical constants, setting a limit on how runny a liquid can be. Now this result is taken into the realm of life sciences.

Fundamental physical constants shape the fabric of the universe we live in. Physical constants are quantities with a value that is generally believed to be both universal in nature and to remain unchanged over time—for example the mass of the electron. They govern nuclear reactions and can lead to the formation of molecular structures essential to life, but their origin is unknown. This research might bring scientists one step closer to determining where these constants come from.

Understanding how water flows in a cup turns out to be closely related to the grand challenge to figure out fundamental constants. Life processes in and between living cells require motion and it is viscosity that sets the properties of this motion. If fundamental constants change, viscosity would change too impacting life as we know it. For example, if water was as viscous as tar life would not exist in its current form or not exist at all. This applies beyond water, so all life forms using the liquid state to function would be affected.

Any change in fundamental constants including an increase or decrease would be equally bad news for flow and for liquid-based life. We expect the window to be quite narrow: for example, viscosity of our blood would become too thick or too thin for body functioning with only a few percent change of some fundamental constants such as the Planck constant or electron charge.

Surprisingly, the fundamental constants were thought to be tuned billions of years ago to produce heavy nuclei in stars and back then life as we know it today didn't exist. There was no need for these constants to be fine-tuned at that point to also enable cellular life billions of years later, and yet these constants turn out to be bio-friendly to flow in and between living cells. An accompanying conjecture is that multiple tunings may have been involved and this then suggests a similarity to biological evolution where traits were acquired independently. Through evolutionary mechanisms, fundamental constants may be the result of nature arriving at sustainable physical structures. It remains to be seen how the principles of evolution can be helpful to understand the origin of fundamental constants.

Kostya Trachenko, Constraints on fundamental physical constants from bio-friendly viscosity and diffusion, Science Advances (2023). DOI: 10.1126/sciadv.adh9024. www.science.org/doi/10.1126/sciadv.adh9024

Evidence of carbonic acid found in interstellar space for the first time

An international team of astrophysicists, astronomers and chemists has found evidence of carbonic acid (HOCOOH) in interstellar space, marking the first time it has been detected in such a setting. In their paper published in The Astrophysical Journal, the group describes their discovery, where it was found, and what it might mean for research into the origins of life.

Prior research has led to the discovery of acetic and formic acid in interstellar space; both are carboxylic acids, as is carbonic acid. All three are believed to be building blocks of life. Finding them in such distant places gives credence to theories that suggest that they were delivered to Earth via comets or meteorites. In this new effort, the researchers were studying the molecular cloud G+0.693-0.027 near the center of the Milky Way when they found evidence of HOCOOH.

Carboxylic acids have a carbon atom and are doubly bonded to an oxygen atom. They are also singly bonded to a hydroxyl group. Carbonic acid is formed here on Earth when CO2 mixes and dissolves in water. It produces the acidic effect in soft drinks. It is also responsible for the increasing acidity of the oceans due to increased amounts of atmospheric CO2. The research team notes that carbonic acid has been observed on several of Jupiter's moons, on comets and on Mercury and Mars—but this is the first time it has been detected in interstellar space. They also note that the presence of carbonic acid in an interstellar molecular cloud suggests a high degree of complexity in the interstellar medium, which means it may also harbor amino-acid-related compounds.

They also found an upper limit to the abundance of HOCOOH with respect to diatomic hydrogen in the molecular cloud, which they suggest hints at the possibility that carbonic acid may be abundant in interstellar space. They note that one of the reasons carbonic acid has not been spotted in interstellar space until now, despite its apparent abundance, is that it is undetectable by radio astronomical observations.

 Miguel Sanz-Novo et al, Discovery of the Elusive Carbonic Acid (HOCOOH) in Space, The Astrophysical Journal (2023). DOI: 10.3847/1538-4357/ace523

Spectroscopy, Explained

Scientists discover a previously unknown way cells break down proteins

Short-lived proteins control gene expression in cells to carry out a number of vital tasks, from helping the brain form connections to helping the body mount an immune defense. These proteins are made in the nucleus and are quickly destroyed once they've done their job.

Despite their importance, the process by which these proteins get broken down and removed from cells once they are no longer needed has eluded scientists for decades—until now.

It is well established that cells can break down proteins by tagging them with a small molecule called ubiquitin. The tag tells the proteasome that the proteins are no longer needed, and it destroys them. 

However, sometimes the proteasome breaks down proteins without the help of ubiquitin tags, leading researchers to suspect that there was another, ubiquitin-independent mechanism of protein degradation.

Researchers now  identified a protein called midnolin that plays a key role in degrading many short-lived nuclear proteins. The study shows that midnolin does so by directly grabbing the proteins and pulling them into the cellular waste-disposal system, called the proteasome, where they are destroyed.

Because the proteins broken down by this process modulate genes with important functions related to the brain, the immune system, and development, scientists may eventually be able to target the process as a way of controlling protein levels to alter these functions and correct any dysfunction.

Xin Gu et al, The midnolin-proteasome pathway catches proteins for ubiquitination-independent degradation, Science (2023). DOI: 10.1126/science.adh5021.

Study shows that astrocytes in the cortex modulate the dominant behavior of male mice

The social behavior of animals has been the key focus of extensive neuroscience and biomedical studies, as it is often aligned with behaviors observed in humans. Better understanding these behaviors and the neural processes underpinning them could ultimately also have implications for the treatment of different psychiatric disorders that affect how humans socialize with others.

Researchers recently conducted a study specifically exploring male dominance behavior among male mice. These behaviours naturally lead to the formation of social hierarchies among groups of mice, with some males accessing more food and water than others. 

A recent paper, published in Nature Neuroscience, highlights the role of astrocytes in the outer layer of the brain (i.e., the cortex), in modulating the dominance behavior of male mice. In addition, it sheds some light on the specific neural processes through which astrocytes modulate these behaviours.

The results gathered by the researchers hint at the involvement of communication between dmPFC astrocytes and neurons in the dominant behaviour of male mice. 

This work implies that astrocytes also play critical role in computing and processing high-order brain functions. It also suggests that such intercellular interplay may decipher the etiology of many psychiatric disorders.

 Kyungchul Noh et al, Cortical astrocytes modulate dominance behavior in male mice by regulating synaptic excitatory and inhibitory balance, Nature Neuroscience (2023). DOI: 10.1038/s41593-023-01406-4

Nguyen T. Phi et al, Control of social hierarchy beyond neurons, Nature Neuroscience (2023). DOI: 10.1038/s41593-023-01392-7

 Unlocking the secrets to brain diseases: When proteins get stuck at the solid phase

Many diseases affecting the brain and nervous system are linked to the formation of protein aggregates, or solid condensates, in cells from their liquid form condensate, but little is known about this process.

This liquid-to-solid transition can trigger the formation of what are called amyloid fibrils. These can further form plaques in neurons causing neurodegenerative diseases such as Alzheimer's.

Biomedical Engineers have now developed sophisticated optical techniques to monitor at close range the process by which these protein aggregates form.

By testing a protein associated with amyotrophic lateral sclerosis—ALS disease, which affected astrophysicist Professor Stephen Hawking—the Sydney engineers closely monitored the transition of this protein from its liquid to solid phase.

Proteins regularly form condensates during liquid-to-liquid phase separation in a wide range of critical and healthy biological functions, such as the formation of human embryos. This process assists biochemical reactions where protein concentrations are critical and also promotes healthy protein–protein interactions. However, this process also increases the risk of dysfunctional aggregation, where unhealthy aggregates of solid proteins form in human cells.

This can lead to aberrant structures associated with neurodegenerative diseases because the proteins no longer exhibit rapid reversibility back to liquid form.  It is therefore crucial to monitor condensate dynamics, as they directly affect pathological states.

The world-first nanoscale optical observation of this process has allowed the team to determine that the transition from liquid to solid protein starts at the interface of the protein condensates. This window onto the phase transition also revealed that the internal structures of these protein agglomerates are heterogenous, where previously they were thought to be homogeneous.

Yi Shen et al, The liquid-to-solid transition of FUS is promoted by the condensate surface, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2301366120

How the 'treadmill conveyor belt' ensures proper cell division

Researchers at the Center for Genomic Regulation (CRG) have discovered how proteins work in tandem to regulate "treadmilling," a mechanism used by the network of microtubules inside cells to ensure proper cell division. The findings are published in the Journal of Cell Biology.

Microtubules are long tubes made of proteins that serve as infrastructure to connect different regions inside of a cell. Microtubules are also critical for cell division, where they are key components of the spindle, the structure which attaches itself to chromosomes and pulls them apart into each new cell.

For the spindle to function properly, cells rely on microtubules to "treadmill." This involves one end of the microtubule (known as the minus end) to lose components while the other (the plus end) adds components. The effect is like that of a treadmill conveyor belt, where the microtubules appear to be moving continuously without changing their overall length.

Treadmilling is crucial for cell division. The most likely theory is that treadmilling helps the cell regulate its attachments to chromosomes by maintaining tension. Because microtubules are often growing from their plus ends, this tension can be provided by constant shrinking from the minus end.

The authors of the study used various isolated proteins known to play a central role in microtubule biology, putting them together in a test tube and visualizing them using a microscope.

Three proteins were found to be critical for regulating treadmilling: KIF2A, a protein belonging to a larger family of proteins that dismantles microtubules, the γ-tubulin ring complex (γ-TuRC), a scaffold for microtubules to grow from, and spastin, an enzyme that acts like a scissor cutting microtubules.

The researchers found that the correct control of treadmilling requires the coordinated action of all three proteins. 

Gil Henkin et al, The minus end depolymerase KIF2A drives flux-like treadmilling of γTuRC-uncapped microtubules, Journal of Cell Biology (2023). DOI: 10.1083/jcb.202304020

Science and non-English-speaking scientists

Most journals offer minimal support for scientists who don't speak fluent English. An analysis of 736 biological-science journals found that only 2 stated that manuscripts would not be rejected solely on the .... A survey of the editors-in-chief of 262 of these journals found that only 6% instructed reviewers not to base their assessments solely on language proficiency. Less than 10% of journals offered author guidelines in at least one language other than English or allowed authors to publish articles in other languages.

Abstract

Nature 
Reference: EcoEvoRxiv preprint (not peer reviewed)

https://ecoevorxiv.org/repository/view/5475/

Paper drinking straws may be harmful and may not be better for the environment than plastic versions, researchers warn

"Eco-friendly" paper drinking straws contain long-lasting and potentially toxic chemicals, a new study has concluded.

Researchers tested 39 brands of straws for the group of synthetic chemicals known as poly- and perfluoroalkyl substances (PFAS).

PFAS were found in the majority of the straws tested and were most common in those made from paper and bamboo, found the study, published in Food Additives & Contaminants.

PFAS are used to make everyday products, from outdoor clothing to non-stick pans, resistant to water, heat and stains. However, they are potentially harmful to people, wildlife and the environment. They break down very slowly over time and can persist over thousands of years in the environment, a property that has led to them being known as "forever chemicals."

They have been associated with a number of health problems, including lower response to vaccines, lower birth weight, thyroid disease, increased cholesterol levels, liver damage, kidney cancer and testicular cancer.

Straws made from plant-based materials, such as paper and bamboo, are often advertised as being more sustainable and eco-friendly than those made from plastic. However, the presence of PFAS in these straws means that's not necessarily true.

The most commonly found PFAS, perfluorooctanoic acid  (PFOA), has been banned globally since 2020.

Also detected were trifluoroacetic acid (TFA) and trifluoromethanesulfonic acid (TFMS), "ultra-short chain" PFAS which are highly water soluble and so might leach out of straws into drinks.

The PFAS concentrations were low, and bearing in mind that most people tend to only use straws occasionally, pose a limited risk to human health. However, PFAS can remain in the body for many years and concentrations can build up over time. Small amounts of PFAS, while not harmful in themselves, can add to the chemical load already present in the body.

The presence of the chemicals in almost every brand of paper straw means it is likely that it was, in some cases, being used as a water-repellent coating, say the researchers.

The presence of PFAS in paper and bamboo straws shows they are not necessarily biodegradable. As they did not detect any PFAS in stainless steel straws, the researchers are advising consumers to use this type of straw—or just avoid using straws at all.

Assessment of poly- and perfluoroalkyl substances (PFAS) in commercially available drinking straws using targeted and suspect screening approaches, Food Additives & Contaminants (2023). DOI: 10.1080/19440049.2023.2240908. www.tandfonline.com/doi/full/1 … 9440049.2023.2240908

Burning Forever Chemicals With Water

Forever Chemicals, also known as PFAS, are extremely useful industrial chemicals, but they can also leak into the environment, your drinking water, and your blood. And they last (practically) forever. But now chemists have a new way to destroy them: burning them with water.

Penguin Breeding Colonies Catastrophically Failing as Ice Vanishes in Antarctica

For most of the year, there is a "skirt" of stable sea ice around Antarctica, attached to the land. This fast ice, as it is known, forms in April, during the Southern Hemisphere's autumn, and persists until January, or high summer. Emperor penguins make their breeding ground on this fast ice, laying their eggs in May and June. The incubation period for emperor penguins is around 65 days, but the chicks are pretty helpless until they fledge – that is, they grow out of their baby fluff into suitable plumage for swimming and diving in the gelid Antarctic waters. This usually happens between December and January. The breeding season of 2022 started off normally; the penguins laid their eggs in the autumn, and incubated and hatched them into the winter. Come spring, disaster struck. The fast ice retreated and broke up early. By the beginning of summer, the extent of the Antarctic sea ice was consistent with the all-time low recorded the previous year, in summer 2021. The region most impacted was the Bellingshausen Sea, towards the west of the Antarctic peninsula, where some regions saw a 100 percent loss in sea ice extent. Every year, emperor penguins return to the same five sites in the Bellingshausen Sea to lay their eggs and raise their chicks. These five colonies range in size from an average of around 650 breeding pairs to 3,500 breeding pairs. By December 2022, four of those five sites disappeared as the ice on which they relied melted into the waves. At only one site, Rothschild Island, with 650 breeding pairs, did chicks manage to fledge successfully. Researchers found no sign of the rest of the babies. Emperor penguin colonies can be found around the entire perimeter of the Antarctic continent, but the breeding failure of these select few in the Bellingshausen Sea represent the first of what is likely to be many.

An early sign of extinction? Maybe!

https://www.nature.com/articles/s43247-023-00927-x

Scientists Design a Colourful New Paint That Could Cut Your Electricity Bill!

Scientists  have designed a new paint that could help reduce our growing reliance on air conditioners and heaters. It comes in an array of colors, and if used properly, it could seriously slash electricity bills and emissions.

The paint is capable of reflecting up to 80 percent of mid-infrared light from the Sun, which is 10 times more reflection than conventional colored paints.

Acne-Causing Bacteria May Actually Be Vital For Healthy Skin:Experts

The skin is the largest organ of the body, and it plays a crucial role as the first line of defense against pathogens and insults from the external environment. It provides important functions like temperature regulation and moisture retention. And despite the misconception that lipids harm your skin by causing oiliness and acne, they actually play a vital role in maintaining the skin barrier.

Lipids – organic compounds that include fats, oils, waxes and other types of molecules – are essential components of the outermost layer of skin. Changes to the skin's lipid composition can disrupt its ability to function as a protective barrier, leading to a range of skin diseases, including eczema and psoriasis. Human skin is colonized by thousands of species of bacteria. One of the most common microbes on the skin, Cutibacterium acnes, or C. acnes, is well known for its potential involvement in causing acne, but its broader effects on skin health are less understood.

Recently researchers found that C. acnes triggers certain skin cells to significantly increase production of lipids that are important to maintaining the skin barrier.

They found that  found that C. acnes induced this increase in lipid production by producing a type of short-chain fatty acid called propionic acid. Propionic acid creates an acidic skin environment that provides a number of benefits, including limiting pathogen growth, reducing staph infections and contributing to anti-inflammatory effects in the gut.

They also identified the specific gene and receptor  that regulate lipid synthesis through C. acnes. Blocking these components also blocked C. acnes-induced lipid synthesis.

New ancient ape from Türkiye challenges the story of human origins

A new fossil ape from an 8.7-million-year-old site in Türkiye is challenging long-accepted ideas of human origins and adding weight to the theory that the ancestors of African apes and humans evolved in Europe before migrating to Africa between nine and seven million years ago.

Analysis of a newly identified ape named Anadoluvius turkae recovered from the Çorakyerler fossil locality near Çankırı with the support of the Ministry of Culture and Tourism in Türkiye, shows Mediterranean fossil apes are diverse and are part of the first known radiation of early hominines—the group that includes African apes (chimpanzees, bonobos and gorillas), humans and their fossil ancestors.

The findings are described in a study published today in Communications Biology authored by an international team of researchers.

These findings further suggest that hominines not only evolved in western and central Europe but spent over five million years evolving there and spreading to the eastern Mediterranean before eventually dispersing into Africa, probably as a consequence of changing environments and diminishing forests.

The members of this radiation to which Anadoluvius belongs are currently only identified in Europe and Anatolia. The conclusion is based on analysis of a significantly well-preserved partial cranium uncovered at the site in 2015, which includes most of the facial structure and the front part of the brain case.

Ayla Sevim-Erol et al, A new ape from Türkiye and the radiation of late Miocene hominines, Communications Biology (2023). DOI: 10.1038/s42003-023-05210-5

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The first observation of neutrinos at CERN's Large Hadron Collider

Neutrinos are tiny and neutrally charged particles accounted for by the Standard Model of particle physics. While they are estimated to be some of the most abundant particles in the universe, observing them has so far proved to be highly challenging, as the probability that they will interact with other matter is low.

To detect these particles, physicists have been using detectors and advanced equipment to examine known sources of neutrinos. Their efforts ultimately led to the observation of neutrinos originating from the sun, cosmic rays, supernovae and other cosmic objects, as well as particle accelerators and nuclear reactors. A long-standing goal in this field of study was to observe neutrinos inside colliders, particle accelerators in which two beams of particles collide with each other. Two large research collaborations, namely FASER (Forward Search Experiment) and SND (Scattering and Neutrino Detector)@LHC, have observed these collider neutrinos for the very first time, using detectors located at CERN's Large Hadron Collider (LHC) in Switzerland. The results of their two studies were recently published in Physical Review Letters.

The FASER and SND@LHC collaboration are two distinct research efforts, both utilizing the LHC at CERN. Recently, these two efforts independently observed the first collider neutrinos, which could open important new avenues for experimental particle physics research.

The FASER collaboration is a large research effort established with the goal of observing light and weakly interacting particles. FASER was the first research group to observe neutrinos at the LHC, using the FASER detector, which is positioned over 400m away from the renowned ATLAS experiment, in a separate tunnel. FASER (and SND@LHC) observe neutrinos produced in the same "interaction region" inside the LHC as ATLAS.

Henso Abreu et al, First Direct Observation of Collider Neutrinos with FASER at the LHC, Physical Review Letters (2023). DOI: 10.1103/PhysRevLett.131.031801

R. Albanese et al, Observation of Collider Muon Neutrinos with the SND@LHC Experiment, Physical Review Letters (2023). DOI: 10.1103/PhysRevLett.131.031802

Researchers find key for transforming cancer cells to muscle in rhabdomyosarcoma

For six years,  some researchers  have been on a mission to transform sarcoma cells into regularly functioning tissue cells. Sarcomas are cancers that form in connective tissues such as muscle. Treatment often involves chemotherapy, surgery, and radiation—procedures that are especially tough on kids. If doctors could transform cancer cells into healthy cells, it would offer patients a whole new treatment option—one that could spare them and their families a great deal of pain and suffering.

A devastating and aggressive type of pediatric cancer, rhabdomyosarcoma (RMS) resembles children's muscle cells. No one knew whether this proposed treatment method, called differentiation therapy, might ever work in RMS. It could still be decades out. But now, thanks to some scientists, it seems like a real possibility.

To carry out their mission, these researchers created a new genetic screening technique. Using genome-editing technology, they hunted down genes that, when disrupted, would force RMS cells to become muscle cells. That's when a protein called NF-Y emerged. With NF-Y impaired, the scientists witnessed an astonishing transformation.

The cells literally turn into muscle. The tumor loses all cancer attributes. They're switching from a cell that just wants to make more of itself to cells devoted to contraction. Because all its energy and resources are now devoted to contraction, it can't go back to this multiplying state. The research is published in the journal Proceedings of the National Academy of Sciences.

This newfound relationship between NF-Y and RMS may set off the chain reaction needed to bring differentiation therapy to patients. And the mission doesn't stop at RMS. The technology could be applicable to other cancer types. If so, scientists may someday work out how to turn other tumors into healthy cells.

 Sroka, Martyna W. et al, Myo-differentiation reporter screen reveals NF-Y as an activator of PAX3–FOXO1 in rhabdomyosarcoma, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2303859120. doi.org/10.1073/pnas.2303859120

How much heat can a human body bear?
There is a fundamental limit to the body's coping ability: it is a fixed goalpost.

Research in 2010 demonstrated that a 'wet-bulb' temperature of 35° Celsius or higher would make it impossible for humans to exhaust metabolic heat, due to our fixed core body temperature.

It proposed this was an effective survivability limit.

The wet-bulb temperature measures the ability to cool by evaporation; it equals normal temperature if relative humidity is 100 percent, and otherwise is lower. 35C is extreme—most places on Earth never experience wet bulbs above 30°C.

But enough global warming could push heat waves in many areas past 35° C. This upended the widely held assumption at the time that humans could adapt to any amount of increased heat, i.e., that the goalposts would move. This goalpost will not.

Wet-bulb temperature is used by meteorologists and climatologists to quantify heat stress. It is a combination of heat and humidity: a high wet bulb can occur in humid places at lower temperatures, as well as in dry places at extremely high temperatures.

New studies are beginning to chart out the road to 35° C.

One study in the US last year found that young, healthy subjects exposed to very hot conditions started to enter hyperthermia (inability to regulate core body temperature) well below 35°C wet bulb, closer to 32° C or less.

This is an important reminder that 35° C was a theoretical upper limit, not a practical one.

On the other hand they would undoubtedly have found a higher tolerance had they done the study in India or Brazil, because physiology does adjust to heat over time (up to a point).

The heat will force us to change how we live, for example shifting outdoor summertime activities to nighttime or just eliminating them.

It remains challenging to measure or predict extreme heat's overall cost to the community in terms of health, work and quality of life.

To do this, climate and health researchers need to develop models that factor in human behavior and adaptation along with physiology, weather, and climate information. We also need to understand what will happen to nature, and seek ways to protect wildlife.

Above all we need to reach net zero carbon emissions as soon as we possibly can to arrest the continuing rise in heat.

India's moon rover confirms sulfur and detects several other elements near the lunar south pole

India's moon rover confirmed the presence of sulfur and detected several other elements near the lunar south pole as it searches for signs of frozen water nearly a week after its historic moon landing, India's space agency said recently. 

The rover's laser-induced spectroscope instrument also detected aluminum, iron, calcium, chromium, titanium, manganese, oxygen and silicon on the lunar surface, the Indian Space Research Organization, or ISRO, said in a post on its website.

The lunar rover had come down a ramp from the lander of India's spacecraft after last Wednesday's touch down near the moon's south pole. The Chandrayan-3 Rover is expected to conduct experiments over 14 days, the ISRO has said.

The rover "unambiguously confirms the presence of sulfur," ISRO said. It also is searching for signs of frozen water that could help future astronaut missions, as a potential source of drinking water or to make rocket fuel.

The rover also will study the moon's atmosphere and seismic activity.

Source: ISRO

Watch this cosmic spectacle:

The cosmic curtain rises Wednesday night with the second full moon of the month - the reason it's considered blue. It's dubbed a super-moon because it's closer to Earth than usual, appearing especially big and bright.

This will be the closest full moon of the year, just 222,043 miles (357,344 kilometers) or so away. That's more than 100 miles (160 kilometers) closer than the Aug. 1 supermoon.

As a bonus, Saturn will be visible as a bright point 5 degrees to the upper right of the moon at sunset in the east-southeastern sky. The ringed planet will appear to circle clockwise around the moon as the night wears on.

If you missed the month's first spectacle, better catch this one. There won't be another blue super-moon until 2037. The first super-moon of 2023 was in July. The fourth and last will be in September.

Enhancing cancer therapy using functionalized photosynthetic bacteria

Targeting malignant tumors with high precision is challenging for biomedical researchers. However, this scenario is likely to witness a paradigm shift in the near future through the use of specially engineered bacteria that can eliminate malignant cells efficiently.

Using bacteria to target cancer cells, or bacterial therapy, can be further enhanced through genetic engineering and nanotechnology. However, its efficacy may be hindered due to technical constraints and the potential development of antibiotic resistance. Hence, it is crucial to achieve the moderate yet effective chemical modification of bacteria for improved biocompatibility and functionality, such that their medical abilities are not compromised.

Recently, certain types of purple photosynthetic bacteria (PPSB) have come into limelight for their potential to address the challenges of bacterial therapy. Exploring this further, researchers published a study in Nano Today that reports the use of chemically modified PPSB for detecting and eliminating hard-to-eradicate cancerous cells in a mouse model.

Researchers selected Rhodopseudomonas palustris (RP) as the optimal bacterium for conducting the studies. "RP demonstrated excellent properties, such as near-infrared (NIR) fluorescence, photothermal conversion, and low cytotoxicity. It absorbs NIR light and produces free radicals—a property that can be utilized to kill cancer cells.

In an attempt to improve the therapeutic efficacy of the isolated strain, the team sought chemical modifications to alter the bacterial membranes. First, they performed membrane PEGylation, or the attachment of polyethylene glycol derivatives to the bacterial cell walls. Prior research indicates that bacterial PEGylation helps in evading host immune response and converts light energy into heat, which can then be utilized to selectively eliminate cancerous cells.

Initial results were encouraging.

 Sheethal Reghu et al, Cancer immunotheranostics using bioactive nanocoated photosynthetic bacterial complexes, Nano Today (2023). DOI: 10.1016/j.nantod.2023.101966

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Sea sponge tissue found to hold bits of DNA from fish living around them

A team of environmental and marine biologists  has found that studying sea sponge tissue can reveal the nature of the fish community living around them. 

Sea sponges live on the ocean floor—once they pick a spot to call home, they anchor themselves to a base and remain fixed in that place for the rest of their existence. They survive by filtering nutrients and oxygen from ocean water as it moves through their porous tissue. They also emit waste.

In this new effort, the researchers  found that the water passing through sea sponge pores also carries DNA from fish that live in the area and that it becomes trapped in the sea sponges' tissues. This DNA provides a record of local biodiversity.

By classifying the fish that shed the DNA via sequencing, researchers were able to create a map of a given underwater ecosystem. They were able to discriminate assemblages by region of the ocean (from Svalbard to Western Greenland, for example) and the depth of the habitat and even the level of protection.

The researchers note that there is generally a high cost associated with conducting ocean biodiversity studies—collecting and studying sea sponges could offer a much cheaper option.

Trapped DNA fragments in marine sponge specimens unveil north Atlantic deep-sea fish diversity, Proceedings of the Royal Society B: Biological Sciences (2023). DOI: 10.1098/rspb.2023.0771. royalsocietypublishing.org/doi … .1098/rspb.2023.0771

Newly-engineered versions of bacterial enzyme reveal how antibiotics could be more potent

Modern medicine depends on antibiotics to treat infections by disabling targets inside bacterial cells. Once inside these cells, antibiotics bind to certain sites on specific enzyme targets to stop bacterial growth. Randomly occurring changes (mutations) in the genes for these targets occur naturally, in some cases making the target harder for the antibiotic to attach to, and that bacterial version resistant to treatment.

For this reason, the more antibiotics have been used over time, the greater the chances that bacterial populations will evolve to have mutants resistant to existing antibiotics, and the more urgent the call for new approaches to keep the treatments from becoming obsolete.

Researchers have for decades studied resistant mutants in hopes that related mechanisms would guide the design of new treatments to overcome resistance. The effort has been limited, however, because naturally occurring resistant mutants represent a small fraction of the mutations that could possibly occur (the complete mutational space), with most drug binding-site mutations to date having been overlooked.

To address this challenge, a new study by researchers to generate the full inventory of mutations in the bacterial species Escherichia coli where the antibiotic rifampicin attaches to and disables an essential bacterial enzyme known as RNA polymerase (RNAP).

The study authors created 760 unique RNAP mutants by replacing each of the 38 amino acid building blocks that make up the rifampicin binding site on E. coli with each of the 20 amino acid options present in nature. Growth of this mutant pool was then tested under different conditions, including treatment with rifampicin.

Published online August 30 in the journal Nature, the study found two mutants, L521Y and T525D, that are hyper-sensitive to rifampicin. Not only does the antibiotic prevent these mutants from growing, it nearly obliterates the mutant bacterial populations. This is a remarkable finding, say the authors, because rifampicin normally does not kill E. coli, or many other bacterial pathogens, but only stops their growth.

This work provides a map of antibiotic-bacterial RNAP interactions that will be of value to chemists working to build on the study effects by changing, not bacterial binding site residues, but instead the structure of rifampicin and other antibiotics so that they bind tighter for increased potency.

These techniques could be applied to map the binding sites of other drug types, and especially to those vulnerable to resistance.

Evgeny Nudler, High-resolution landscape of an antibiotic binding site, Nature (2023). DOI: 10.1038/s41586-023-06495-6. www.nature.com/articles/s41586-023-06495-6

What mummies reveal: The scents ancient Egyptians used

In an innovative endeavor to create a sensory bridge to the ancient past, a team of researchers has recreated one of the scents used in the mummification of an important Egyptian woman more than 3,500 years ago.

The research team found that the balms contained a blend of beeswax, plant oil, fats, bitumen, Pinaceae resins (most likely larch resin), a balsamic substance, and dammar or Pistacia tree resin.

Coined "the scent of the eternity," the ancient aroma will be presented at the Moesgaard Museum in Denmark in an upcoming exhibition, offering visitors a unique sensory experience to encounter firsthand an ambient smell from antiquity—and catch a whiff of the ancient Egyptian process of mummification.

The team's research centered on the mummification substances used to embalm the noble lady Senetnay in the 18th dynasty, circa 1450 BCE. The researchers utilized advanced analytical techniques—including gas chromatography-mass spectrometry, high-temperature gas chromatography-mass spectrometry, and liquid chromatography-tandem mass spectrometry—to reconstruct the substances that helped to preserve and scent Senetnay for eternity. Their research has been published in Scientific Reports.

Researchers analyzed balm residues found in two canopic jars from the mummification equipment of Senetnay that were excavated over a century ago by Howard Carter from Tomb KV42 in the Valley of the Kings.

These complex and diverse ingredients, unique to this early time period, offer a novel understanding of the sophisticated mummification practices and Egypt's far-reaching trade-routes.

The ingredients in the balm make it clear that the ancient Egyptians were sourcing materials from beyond their realm from an early date.

Among those imported ingredients were larch tree resin, which likely came from the northern Mediterranean, and possibly dammars, which come exclusively from trees in Southeast Asian tropical forests. If the presence of dammar resin is confirmed, as in balms recently identified from Saqqara dating to the 1st millennium BCE, it would suggest that the ancient Egyptians had access to this Southeast Asian resin via long-distant trade almost a millennium earlier than previously known.

 Barbara Huber, Biomolecular characterization of 3500-year-old ancient Egyptian mummification balms from the Valley of the Kings, Scientific Reports (2023). DOI: 10.1038/s41598-023-39393-y. www.nature.com/articles/s41598-023-39393-y

Scientists devise new way to eliminate cancer cells' evasion of immune system

Tumour cells are notoriously skilled masters of immune disguise and, in many ways, real-life versions of what it's like hiding under the fictional invisibility cloak.

But new research suggests that cancer cells can be forced to lose their invisibility and reveal their presence, factors that can help boost anti-cancer therapeutic activity and guarantee the death of tumor cells.

The new research, conducted by an international collaboration of scientists,  involved an elegant series of experiments in both human and animal cell lines. The research, still in the laboratory phase, is aimed at forcing cancer cells to reveal their antigens, the biomarkers on their surfaces. Once the antigens are revealed, aggressive immune forces can locate and destroy the cancer.

Cancer cells downregulate their antigen presentation molecules to maintain their invisibility—avoiding detection by immune cells. Prior research has focused on how to help immune cells better recognize tumor cells. The new investigation demonstrates that there might be another way to aid the immune system in overcoming cancer cell evasion: targeting the cancer cells themselves.

Decreased antigen presentation contributes to the ability of cancer cells to evade the immune system. So researchers  reprogrammed cancer cells in the lab, a change that transformed the cells into tumour-derived antigen-presenting cells—APCs. Once transformed, the cells were visible to the immune system. They used the minimal gene regulatory network of type 1 conventional dendritic cells to reprogram cancer cells into professional antigen-presenting cells, tumor-APCs.

The study lays the foundation for the development of immunotherapies that would allow reprogramming of cancer cells to antigen-presenting cells in situ.

The team of scientists borrowed a page from Mother Nature to arrive their unique way to peel away the invisibility cloak of tumor cells. In the blood exists a trio of cell types known as antigen presenting cells, or APCs. But this trio is not just any old group of three, they are known in the official biological nomenclature as professional APCs, and they include macrophages, B cells and dendritic cells. Their job as a professional APC (each has other important duties) is to present potentially dangerous antigens to T cells.

The multinational group of scientists demonstrated that cancer cells can be reprogrammed and made to cooperate in the business of making tumour antigens visible to killer T cells. Using transcription factors associated with antigen-presenting conventional type 1 dendritic cells, the team created tumor antigen-presenting cells in both mouse and human cancer cell lines. Once reprogrammed by way of transcription factors, these transformed cells were able to induce effective killer T cell activity. Reprogramming restored the expression of antigen presentation complexes and costimulatory molecules on the surfaces of tumour cells, allowing the presentation of endogenous tumour antigens on MHC-I [major histocompatibility complex-1] and facilitating targeted killing by CD8+ T cells.

Part 1

Functionally, tumor-APCs engulfed and processed proteins and dead cells, secreted inflammatory cytokines, and cross-presented antigens to naïve CD8⁺ T cells. Human primary tumor cells could also be reprogrammed to increase their capability to present antigen and to activate patient-specific tumor-infiltrating lymphocytes.

What the team actually developed was a new way to lift the cloak of invisibility from cancer cells, which are infamously adept masters of disguise. When the researchers injected lab-treated tumor-APCs directly into established melanoma tumors in mice, they observed decreased tumor growth, improved responsiveness to immune checkpoint inhibition therapy, and increased survival rates among the animals.

 Olga Zimmermannova et al, Restoring tumor immunogenicity with dendritic cell reprogramming, Science Immunology (2023). DOI: 10.1126/sciimmunol.add4817

Part 2

Boys who smoke in their early teens found to risk passing on harmful epigenetic traits to future children

A new study suggests boys who smoke in their early teens risk damaging the genes of their future children, increasing their chances of developing asthma, obesity and low lung function.

Research published in Clinical Epigenetics is the first human study to reveal the biological mechanism behind the impact of fathers' early teenage smoking on their children. Researchers  investigated the epigenetic profiles of 875 people, aged 7 to 50, and the smoking behaviours of their fathers.

They found epigenetic changes at 19 sites mapped to 14 genes in the children of fathers who smoked before the age of 15. These changes in the way DNA is packaged in cells (methylation) regulate gene expression (switching them on and off) and are associated with asthma, obesity and wheezing.

These studies have shown that the health of future generations depends on the actions and decisions made by young people today—long before they are parents—in particular for boys in early puberty and mothers/grandmothers both pre-pregnancy and during pregnancy.

Changes in epigenetic markers were much more pronounced in children whose fathers started smoking during puberty than those whose fathers had started smoking at any time before conception. Early puberty may represent a critical window of physiological changes in boys. This is when the stem cells are being established which will make sperm for the rest of their lives.

 Negusse Kitaba et al, Fathers' preconception smoking and offspring DNA methylation., Clinical Epigenetics (2023). DOI: 10.1186/s13148-023-01540-7

COVID infection risk rises the longer you are exposed — even for vaccinated people

Scientists Warn 1 Billion People on Track to Die From Climate Change

The fossil fuels that humanity burns today will be a death sentence for many lives tomorrow.

A recent review of 180 articles on the human death rate of climate change has settled on a deeply distressing number. Over the next century or so, conservative estimates suggest a billion people could die from climate catastrophes, possibly more.

One is a rough rule of thumb called the '1000-ton rule'. Under this framework, every thousand tons of carbon that humanity burns is said to indirectly condemn a future person to death.

Groundwater depletion rates in India could triple in coming decades as climate warms, study warns

A new  study finds that farmers in India have adapted to warming temperatures by intensifying the withdrawal of groundwater used for irrigation. If the trend continues, the rate of groundwater loss could triple by 2080, further threatening India's food and water security.

Reduced water availability in India due to ground water depletion and climate change could threaten the livelihoods of more than one-third of the country's 1.4 billion residents and has global implications. India recently overtook China to become the world's most populous nation and is the second-largest global producer of common cereal grains including rice and wheat.

This is of concern, given that India is the world's largest consumer of groundwater and is a critical resource for the regional and global food supply.

Without policies and interventions to conserve groundwater, we find that warming temperatures will likely amplify India's already existing groundwater depletion problem, further challenging India's food and water security in the face of climate change.

 Nishan Bhattarai, Warming temperatures exacerbate groundwater depletion rates in India, Science Advances (2023). DOI: 10.1126/sciadv.adi1401. www.science.org/doi/10.1126/sciadv.adi1401

Human ancestors nearly went extinct
Roughly 900,000 years ago, climate changes sweeping the globe might have pushed our distant ancestors to the brink of extinction. The unknown human-like species was reduced to just 1,280 breeding individuals, creating a genetic bottleneck that is still detectable in the DNA of modern-day humans. The population didn’t expand for more than 100,000 years, after which it bloomed again and the progenitors of our species and of our extinct relatives, the Denisovans and the Neanderthals, emerged.

The work, published in Science, suggests a drastic reduction in the population of our ancestors well before our species, Homo sapiens, emerged. The population of breeding individuals was reduced to just 1,280 and didn’t expand again for another 117,000 years.

About 98.7% of human ancestors were lost then.

The fossil record in Africa and Eurasia between 950,000 and 650,000 years ago is patchy and that “the discovery of this bottleneck may explain the chronological gap.

The researchers’ method allowed them to reconstruct ancient population dynamics on the basis of genetic data from present-day humans. By constructing a complex family tree of genes, the team was able to examine the finer branches of the tree with greater precision, identifying significant evolutionary events.

The technique put the spotlight on the period 800,000 to one million years ago — for which there is much unknown — in a way that hasn’t been done before.

Around 813,000 years ago, the population of pre-humans began to swell again. How our ancestors managed to survive, and what allowed them to flourish once more, remains unclear, though.

https://www.science.org/doi/10.1126/science.abq7487?utm_source=Natu...