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Comment by Dr. Krishna Kumari Challa on December 4, 2020 at 5:48am

**How plants compete for underground real estate affects climate change and food production

You might have observed plants competing for sunlight—the way they stretch upwards and outwards to block each other's access to the sun's rays—but out of sight, another type of competition is happening underground. In the same way that you might change the way you forage for free snacks in the break room when your colleagues are present, plants change their use of underground resources when they're planted alongside other plants.

In a paper published today in Science, an international team of researchers  sheds light on the underground life of plants. Their research used a combination of modeling and a greenhouse experiment to discover whether plants invest differently in root structures when planted alone versus when planted alongside a neighbour.

Plants make two different types of roots: fine roots that absorb water and nutrients from the soil, and coarse transportation roots that transport these substances back to the plant's center. Plant "investment" in roots involves both the total volume of roots produced and the way in which these roots are distributed throughout the soil. A plant could concentrate all of its roots directly beneath its shoots, or it could spread its roots out horizontally to forage in the adjacent soil—which risks competition with the roots of neighboring plants.

The team's model predicted two potential outcomes for root investment when plants find themselves sharing soil. In the first outcome, the neighboring plants "cooperate" by segregating their root systems to reduce overlap, which leads to producing less roots overall than they would if they were solitary. In the second outcome, when a plant senses reduced resources on one side due to the presence of a neighbor, it shortens its root system on that side but invests more in roots directly below its stem.

Natural selection predicts this second scenario, because each plant acts to increase its own fitness, regardless of how those actions impact other individuals. If plants are very close together, this increased investment in root volume, despite segregation of those roots, could result in a tragedy of the commons, whereby the resources (in this case, soil moisture and nutrients) are depleted.

When this was tested on pepper plants, the team discovered that the outcome depends on how close a pair of plants are to each other. If planted very close together, plants will be more likely to heavily invest in their root systems to try to outcompete each other for finite underground resources; if they are planted further apart, they will likely invest less in their root systems than a solitary plant would.

Specifically, they found that when planted near others, pepper plants increased investment in roots locally and reduced how far they stretched their roots horizontally, to reduce overlap with neighbors. There was no evidence for a "tragedy of the commons" scenario, since there was no difference in the total root biomass or relative investment in roots compared to aboveground structures (including the number of seeds produced per plant) for solitary versus co-habiting plants.

 C. Cabal el al., "The exploitative segregation of plant roots," Science (2020). science.sciencemag.org/cgi/doi … 1126/science.aba9877

https://phys.org/news/2020-12-underground-real-estate-affects-clima...

Comment by Dr. Krishna Kumari Challa on December 4, 2020 at 5:42am

Physicists capture the sound of a 'perfect' fluid

For physicists, a perfect flow is more specific, referring to a fluid that flows with the smallest amount of friction, or viscosity, allowed by the laws of quantum mechanics. Such perfectly fluid behaviour is rare in nature, but it is thought to occur in the cores of neutron stars and in the soupy plasma of the early universe.

Now physicists have created a perfect fluid in the laboratory, and listened to how sound waves travel through it. The recording is a product of a glissando of sound waves that the team sent through a carefully controlled gas of elementary particles known as fermions. The pitches that can be heard are the particular frequencies at which the gas resonates like a plucked string.

The researchers analyzed thousands of sound waves traveling through this gas, to measure its "sound diffusion," or how quickly sound dissipates in the gas, which is related directly to a material's viscosity, or internal friction.

Surprisingly, they found that the fluid's sound diffusion was so low as to be described by a "quantum" amount of friction, given by a constant of nature known as Planck's constant, and the mass of the individual fermions in the fluid.

This fundamental value confirmed that the strongly interacting fermion gas behaves as a perfect fluid, and is universal in nature. The results, published today in the journal Science, demonstrate the first time that scientists have been able to measure sound diffusion in a perfect fluid.

Scientists can now use the fluid as a model of other, more complicated perfect flows, to estimate the viscosity of the plasma in the early universe, as well as the quantum friction within neutron stars—properties that would otherwise be impossible to calculate. Scientists might even be able to approximately predict the sounds they make.

"Universal sound diffusion in a strongly interacting Fermi gas" Science (2020). science.sciencemag.org/cgi/doi … 1126/science.aaz5756

https://phys.org/news/2020-12-physicists-capture-fluid.html?utm_sou...

Comment by Dr. Krishna Kumari Challa on December 3, 2020 at 12:01pm

Organic Molecules

Comment by Dr. Krishna Kumari Challa on December 3, 2020 at 11:30am

Peer Review: Implementing a "publish, then review" model of publishing

From July 2021 eLife will only review manuscripts already published as preprints, and will focus its editorial process on producing public reviews to be posted alongside the preprints.

https://elifesciences.org/articles/64910?utm_source=content_alert&a...

Comment by Dr. Krishna Kumari Challa on December 3, 2020 at 11:23am

Engineering a viral solution to cancer

Virotherapy is a treatment using biotechnology to convert viruses into therapeutic agents by reprogramming viruses to treat diseases. There are three main branches of virotherapy: anti-cancer oncolytic viruses,

While doctors can successfully treat some types of skin cancer at the surface with human-engineered viruses, scientists have yet to find a way to inject these types of viruses to seek and destroy other cancers in the body, such as lung cancer.

But medical researchers at Case Western Reserve University and Emory University are reporting remarkable success in eliminating human cancer cells in mouse models by injecting a modified strain of adenovirus into the bloodstream.

Oncolytic viruses, some found in nature and others modified in the laboratory, are a class of viruses that can infect and kill tumor cells, reproducing efficiently in the tumor without harming healthy cells.

These Scientists performed cryo-electron microscopy and structural modeling to visualize the engineered adenovirus generated by other scientists. Each change in the engineered virus allowed it to evade a particular defense by the body.

 tweaked the adenovirus (named the Ad5-3M virus, indicating three different engineered mutations) to successfully skirt three antiviral immune responses.

Those three responses were:

• Binding: Factors in the blood itself bind the virus and try to clear it through the liver.

• Cytokine storm: Flexible loops on the structure of the virus interact with the body’s host cells, triggering a massive and possibly deadly release of a group of proteins or peptides called cytokines.

• Pathogen clearance: Multiple components of the immune system act in a concerted way to clear pathogens from the body.

https://thedaily.case.edu/engineering-a-viral-solution-to-cancer/

https://researchnews.cc/news/3902/Engineering-a-viral-solution-to-c...

Comment by Dr. Krishna Kumari Challa on December 3, 2020 at 11:08am

Reversal of biological clock restores vision in old mice

‘Reprogramming’ approach seems to makes old cells young again.

anti-ageing treatment restores sight in mice

Scientists recently have restored sight in mice using a "milestone" treatment that returns cells to a more youthful state and could one day help treat glaucoma and other age-related diseases.

The process offers the tantalising possibility of effectively turning back time at the cellular level, helping cells recover the ability to heal damage caused by injury, disease and age.

The treatment is based on the properties that cells have when the body is developing as an embryo. At that time, cells can repair and regenerate themselves, but that capacity declines rapidly with age.

The scientists reasoned that if cells could be induced to return to that youthful state, they would be able to repair damage.

To turn back the clock, they modified a process usually used to create the "blank slate" cells known as induced pluripotent stem cells.

Those cells are created by injecting a cocktail of four proteins that help reprogramme a cell.

The team did not want to reprogramme cells all the way back to that blank-slate status, but to restore them to a more youthful condition.

So they tweaked the cocktail, using just three of the "youth-restoring" proteins -- dubbed OSK -- in the hope they could turn the clock back to just the right point.

They targeted the retinal ganglion cells in the eye, which are linked to the brain through connections called axons.

These axons form the optic nerve -- and damage to them caused by injury, ageing or disease causes poor vision and blindness.

To test the effects of the cocktail, they first injected OSK into the eyes of mice with optic nerve injuries.

They saw a twofold increase in the number of surviving retinal ganglion cells and a fivefold increase in nerve regrowth.

The treatment allowed the nerves to grow back towards the brain. Normally they would simply die.

https://www.nature.com/articles/d41586-020-03403-0#:~:text=Research....

https://researchnews.cc/news/3916/-Milestone--anti-ageing-treatment...

Comment by Dr. Krishna Kumari Challa on December 3, 2020 at 9:30am

**

Protein molecules in cells function as miniature antennas

Researchers led by Josef Lazar of the Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences (IOCB Prague) have demonstrated that molecules of fluorescent proteins act as antennas with optical properties (i.e. the ability to absorb and emit light) dependent on their spatial orientation. First discovered in jellyfish, fluorescent proteins are nowadays widely used in studies of molecular processes in living cells and organisms. The newly described properties of these molecules will find applications in basic biological research as well as in novel drug discovery. A team of researchers from IOCB Prague, the Institute of Microbiology, and the Institute of Molecular Genetics of the Czech Academy of Sciences has published the findings in the journal Proceedings of the National Academy of Sciences.

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Carbon dioxide converted to ethylene—the 'rice of the industry'

In recent times, electrochemical conversion (e-chemical) technology—which converts carbon dioxide to high-value-added compounds using renewable electricity—has gained research attention as a carbon capture utilization (CCU) technology. This green carbon resource technology employs electrochemical reactions using carbon dioxide and water as the only feedstock chemical to synthesize various compounds, instead of conventional fossil fuels. Electrochemical CO2 conversion can produce value-added and important molecules in the petrochemical industry such as carbon monoxide and ethylene. Ethylene, referred to as the 'rice of the industry,' is widely used to produce various chemical products and polymers, but it is more challenging to produce from electrochemical CO2 reduction. The lack of understanding of the reaction pathway by which carbon dioxide is converted to ethylene has limited development of high-performance catalyst systems and in advancing its application to produce more valuable chemicals.

Comment by Dr. Krishna Kumari Challa on December 3, 2020 at 9:21am

Plant-generated electricity

Comment by Dr. Krishna Kumari Challa on December 3, 2020 at 9:21am

How microorganisms can produce renewable energy for us

We can generate electricity from microorganisms as an alternative to the usual power from water, wind, solar or steam.

Scientists have been studying the ability of microorganisms - the smallest living things on Earth—to produce energy other than for their natural activities for more than a century. This transformation is what scientists call a bioelectrochemical system.

Microbial fuel cell (MFC) is one form of bioelectrochemical system.

This system generally has one anode chamber (negative electrode) and one cathode chamber (positive electrode). MFC works in a similar way to batteries.

Microorganisms decompose organic or inorganic matters (or substrates) in the anode chamber to produce electrons. These electrons flow from anode to cathode via an external circuit made of conductive materials, such as copper-based wires, to generate electricity.

Deciding on the types of microorganism to generate the energy is an influential factor.

To date, the groups of microorganisms that demonstrate the ability to transfer electrons from their cells to the electrodes—called exoelectrogens – are in particular Geobacter and Shewnella.

Geobacter sulfurreducens KN400 can generate up to 3.9 Watts of electricity per square meter (W/m²) of anode area. Shewanella putrefaciens produces up to 4.4 W/m².

For its spaceship, NASA generates energy from Shewanella oneidensis bacteria.

Other microorganisms such as Rhodopseudomonas palustris DX1, Candida melibiosica, Saccharomyces ... also demonstrate exoelectrogenic capabilities.

A new exoelectrogenic microorganism is Desulfuromonas acetexigens.

Exoelectrogens can be obtained from various environments, such as waste water, compost, manure, dirt, river or lake sediments, swamps and marine ecosystems.

https://theconversation.com/this-is-how-microorganisms-can-produce-...

Comment by Dr. Krishna Kumari Challa on December 3, 2020 at 9:05am

Cancer cells 'remove blindfold' to spread

Cunning ways of cancer cells

Cancer cells spread by switching on and off abilities to sense their surroundings, move, hide and grow new tumours, a new study has found.

This sensitivity to their surroundings is the key ability that makes small numbers of cancer cells better at spreading than other cells in a tumour, scientists  discovered.

The researchers developed a new method combining evolutionary biology and artificial intelligence techniques to study the movement and shape of cancer cells in more detail than ever, to learn why some can move more easily to different parts of the body and grow new tumours.

They found some cells displayed an apparent 'awareness' and ability to react to their surroundings, that was previously thought to be lost in of cancer. This means they may be able to adapt their shape to navigate barriers like blood vessel walls or other competing cells far more efficiently in order to replicate elsewhere.

 A phenotypic switch in the dispersal strategy of breast cancer cells selected for metastatic colonisation, Proceedings of the Royal Society B (2020). rspb.royalsocietypublishing.or … .1098/rspb.2020.2523

https://phys.org/news/2020-12-cancer-cells-blindfold.html?utm_sourc...

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