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Comment by Dr. Krishna Kumari Challa on April 19, 2023 at 10:03am

Quantum liquid becomes solid when heated!

Solids can be melted by heating, but in the quantum world it can also be the other way around: In a joint effort, an experimental team show how a quantum liquid forms supersolid structures through heating. The scientists obtained a first phase diagram for a supersolid at finite temperature.

Supersolids are a relatively new and exciting area of research. They exhibit both solid and superfluid properties simultaneously. In 2019, three research groups were able to demonstrate this state for the first time beyond doubt in ultracold quantum gases.

To explore the effect of thermal fluctuation, researchers developed and published in Nature Communications a theoretical model that can explain the experimental results and underlines the thesis that heating the quantum liquid can lead to the formation of a quantum crystal. The theoretical model shows that as the temperature rises, these structures can form more easily.

The surprising behavior, which contradicts our everyday observation, arises from the anisotropic nature of the dipole-dipole interaction of the strongly magnetic atoms of dysprosium.

 J. Sánchez-Baena et al, Heating a dipolar quantum fluid into a solid, Nature Communications (2023). DOI: 10.1038/s41467-023-37207-3

Comment by Dr. Krishna Kumari Challa on April 19, 2023 at 9:51am

Researchers develop carbon-negative concrete

A viable formula for a carbon-negative, environmentally friendly concrete that is nearly as strong as regular concrete has been developed by researchers.

In a proof-of-concept work, the researchers infused regular cement with environmentally friendly biochar, a type of charcoal made from organic waste, that had been strengthened beforehand with concrete wastewater. The biochar was able to suck up to 23% of its weight in carbon dioxide from the air while still reaching a strength comparable to ordinary cement.

The research could significantly reduce carbon emissions of the concrete industry, which is one of the most energy- and carbon-intensive of all manufacturing industries.

Zhipeng Li et al, Towards sustainable industrial application of carbon-negative concrete: Synergistic carbon-capture by concrete washout water and biochar, Materials Letters (2023). DOI: 10.1016/j.matlet.2023.134368

Comment by Dr. Krishna Kumari Challa on April 18, 2023 at 11:59am

Comment by Dr. Krishna Kumari Challa on April 18, 2023 at 9:48am

Dark Matter Matters

Comment by Dr. Krishna Kumari Challa on April 18, 2023 at 9:37am

Income rank linked to experience of physical pain, irrespective of whether in a rich or poor country, study suggests

A new study of worldwide polling data suggests that a person's income rank relative to their peers is linked to their experience of physical pain, with a lower income rank linked to a higher likelihood of experiencing pain. It is the first time such a relationship has been shown.

The study found the link to persist, to the same degree, irrespective of whether the person lives in a rich country or a poor country. Income rank is the position of an individual's absolute personal income amount in a list of those amounts ordered from lowest to highest. The higher the position in the list, the higher the income rank.

 Having less than others is physically painful: Income rank and pain around the world, Social Psychological and Personality Science (2023). DOI: 10.1177/19485506231167928

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Comment by Dr. Krishna Kumari Challa on April 18, 2023 at 8:54am

The Fight Against Misinformation with Dr. Sander van der Linden

Comment by Dr. Krishna Kumari Challa on April 17, 2023 at 11:46am

To understand the mechanism, one must know how cyclic peptides are structured: they consist of a central ring structure to which side chains are attached. The molecules are flexible and can dynamically change their structure to adapt to their environment.

 simulations reveal in detail how a cyclic peptide penetrates the membrane: First, the molecule anchor itself to the membrane’s surface, before penetrating it perpendicular to the membrane. It then changes its three-​dimensional shape while passing through, rotating once about its longitudinal axis before reaching the other side of the membrane, where it exits again.

These changes in shape have to do with the different environments the molecule experiences as it moves through the membrane: The body consists largely of water. Both inside and outside of cells, biochemical molecules are mostly present in aqueous solution. Cell membranes, on the other hand, are made up of fatty acids, so water-​repellent conditions prevail within them. To enable it to cross the membrane, the cyclic peptide changes its three-​dimensional shape to briefly become as hydrophobic as possible.

For the present study, the researchers investigated eight different cyclic peptides. These are model peptides with no medicinal effect – scientists at pharmaceutical giant Novartis developed them for basic research.

The new findings can now be used in discovering cyclic peptides as new drug candidates. However, the researchers point out a certain trade-​off: there are side chains that provide ideal conditions for cyclic peptides to anchor to the membrane surface, but that make it difficult for the peptides to cross the membrane. This new knowledge helps researchers to give advance thought to which side chains they want to use and where on the molecule they are most helpful. All of this could speed up drug discovery and development by ensuring right from the outset that researchers are investigating potential active ingredients that can eventually be taken as a tablet.

https://pubs.acs.org/doi/10.1021/acs.jmedchem.2c01837

Linker SM, Schellhaas C, Kamenik AS, Veldhuizen MM, Waibl F, Roth HJ, Fouché M, Rodde S, Riniker S: Lessons for Oral Bioavailability: How Conformationally Flexible Cyclic Peptides Enter and Cross Lipid Membranes, Journal of Medicinal Chemistry 2023, 66: 2773, doi: external page10.1021/acs.jmedchem.2c01837call_made

Part 2

Comment by Dr. Krishna Kumari Challa on April 17, 2023 at 11:42am

How drugs get into the blood

Computer simulations have helped researchers understand in detail how pharmaceutically active substances cross cell membranes. These findings can now be used to discover new drug candidates more efficiently.

There is a need for new drugs. For example, many of the antibiotics that we have been using for a long time are becoming less effective. Chemists and pharmaceutical scientists are frantically searching for new active substances, especially those that can penetrate cell membranes, as these are the only ones that patients can take orally in the form of a tablet or syrup. Only these active ingredients pass through the intestinal wall in the small intestine and enter the bloodstream to reach the affected area in the body. For active ingredients that cannot penetrate the cell membrane, physicians have no choice but to inject them directly into the bloodstream.

That is why researchers are trying to understand which molecules can penetrate cell membranes and how exactly they do this. For one important and promising class of substances – cyclic peptides – chemists  have now decoded additional details of the relevant mechanism. 

Only modelling allows researchers such detailed, high-​resolution insights.

Cyclic peptides are ring-​shaped molecules that are much larger than the small molecules that make up the majority of today’s drugs. In some areas of application, however, chemists and pharmaceutical scientists are coming up against their limits with small molecules, which is why they are turning to larger molecules like the cyclic peptides. This substance class includes many pharmaceutically active natural substances, such as cyclosporine, an immunosuppressant that for decades has been used after organ transplants, and many antibiotics.

Using computer modelling and a lot of supercomputer power, researchers were able to elucidate how cyclic peptides similar to cyclosporine cross a membrane.

Part 1 

Comment by Dr. Krishna Kumari Challa on April 17, 2023 at 8:56am

Link between a vitamin deficiency and  'double-jointedness' and hypermobile Ehlers-Danlos  syndrome

Researchers have discovered a possible genetic cause for hypermobility (commonly known as double-jointedness) and a range of associated connective tissue disorders such as hypermobile Ehlers-Danlos syndrome, according to preliminary findings published in the journal Heliyon.

You may know someone with overly flexible joints, a friend or family member who can easily slide into a split or bend limbs to impossible angles. But hypermobility is a more serious condition than being "double-jointed."

For those with hypermobile Ehlers-Danlos syndrome (EDS), the same conditions that create fragile connective tissue can cause a range of symptoms that, on the surface, can seem unrelated: physical conditions such as joint pain, chronic fatigue, thin tooth enamel, dizziness, digestive trouble and migraines; and psychiatric disorders, such as anxiety and depression. Women with hypermobile EDS may also be at increased risk for endometriosis or uterine fibroids.

Researchers have long struggled to find the cause of hypermobility and hypermobile EDS. Of the 13 subtypes of EDS, hypermobile EDS comprises more than 90% of the cases. But until this study, hypermobile EDS was the only subtype without a known genetic correlate. As a result, symptoms have often been treated individually rather than as the result of a single cause.

Researchers now have linked hypermobility to a deficiency of folate—the natural form of vitamin B9—caused by a variation of the MTHFR gene.

Those with this genetic variant can't metabolize folate, which causes unmetabolized folate to accumulate in the bloodstream. The folate deficiency may prevent key proteins from binding collagen to the extracellular matrix. This results in more elastic connective tissue, hypermobility, and a potential cascade of associated conditions.

The discovery could help doctors more accurately diagnose hypermobility and hypermobile EDS by looking for elevated folate levels in blood tests as well as the MTHFR genetic variant.

Jacques Courseault et al, Folate-dependent hypermobility syndrome: A proposed mechanism and diagnosis, Heliyon (2023). DOI: 10.1016/j.heliyon.2023.e15387

Comment by Dr. Krishna Kumari Challa on April 16, 2023 at 1:30pm

What Is an Annular Eclipse?

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