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Comment by Dr. Krishna Kumari Challa on December 24, 2020 at 9:42am

Tiny Medical Devices with Shape Memory Polymers

Comment by Dr. Krishna Kumari Challa on December 24, 2020 at 9:33am

Making jet fuel out of carbon dioxide

A team of researchers affiliated with several institutions in the U.K. and one in Saudi Arabia has developed a way to produce jet fuel using carbon dioxide as a main ingredient. In their paper published in the journal Nature Communications, the group describes their process and its efficiency.

The researchers used a process called the organic combustion method to convert carbon dioxide in the air into jet fuel and other products. It involved using an iron catalyst (with added potassium and manganese) along with hydrogen, citric acid and carbon dioxide heated to 350 degrees C. The process forced the carbon atoms apart from the oxygen atoms in CO₂ molecules, which then bonded with hydrogen atoms, producing the kind of hydrocarbon molecules that comprise liquid jet fuel. The process also resulted in the creation of water molecules and other products.

Testing showed that over 20 hours, the process converted 38% of the carbon dioxide in a pressurized chamber into jet fuel and other products. The jet fuel made up 48% of the produced products—the others were water, propylene and ethylene. The researchers also note that using this fuel in aircraft would be carbon-neutral because burning it would release the same amount of carbon dioxide that was used to make it.

The researchers also claim their process is less expensive than other methods used to produce fuel for airplanes, such as those that convert hydrogen and water into fuel—primarily because it uses less electricity. They also point out that conversion systems could be installed in plants that currently emit a lot of carbon dioxide, such as coal fired power plants.

Benzhen Yao et al. Transforming carbon dioxide into jet fuel using an organic combustion-synthesized Fe-Mn-K catalyst, Nature Communications (2020). DOI: 10.1038/s41467-020-20214-z

https://phys.org/news/2020-12-jet-fuel-carbon-dioxide.html?utm_sour...

Comment by Dr. Krishna Kumari Challa on December 24, 2020 at 9:31am

Four ways microbial fuel cells might revolutionize electricity production in the future

The world population is estimated to reach 9.5 billion by 2050. Given that most of our current energy is generated from fossil fuels, this creates significant challenges when it comes to providing enough sustainable electricity while mitigating climate change.

One idea that has gained traction over recent years is generating electricity using bacteria in devices called microbial fuel cells (MFCs). These fuel cells rely on the ability of certain naturally occurring microorganisms that have the ability to "breathe" metals, exchanging electrons to create electricity. This process can be fuelled using substances called substrates, which include organic materials found in wastewater.

At the moment microbial fuel cells are able to generate electricity to power small devices such as calculators, small fans and LEDs.

https://theconversation.com/four-ways-microbial-fuel-cells-might-re...

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Christmas trees can be green because of a photosynthetic short-cut

How can conifers that are used for example as Christmas trees keep their green needles over the boreal winter when most trees shed their leaves? Science has not provided a good answer to this question but now an international team of scientists, including researchers from Umeå University, has deciphered that a short-cut in the photosynthetic machinery allows the needles of pine trees to stay green. The study was published in the journal Nature Communications.

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Protein tells developing cells to stick together

Tohoku University scientists have, for the first time, provided experimental evidence that cell stickiness helps them stay sorted within correct compartments during development. How tightly cells clump together, known as cell adhesion, appears to be enabled by a protein better known for its role in the immune system. The findings were detailed in the journal Nature Communications.

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Comment by Dr. Krishna Kumari Challa on December 24, 2020 at 9:20am

Play sport or watch it? You’re probably emitting an astonishing amount of CO₂!

Few people would stop to consider if their sporting activities damage the environment. But research shows people in some places use a huge chunk of their “personal carbon budget” driving to and from sport events each year – either to watch or participate, or to transport children. Travel for soccer, swimming, cricket, football, basketball and tennis featured most commonly, followed by gym, jogging, walking and golf. The analysis assumed walking and biking to an activity emits no greenhouse gases. Public transport accounts for less than 0.02 kilograms per kilometre (kg/km). A combustion engine car produces an average 0.29 kg/km. Such sport-related travel behaviour may be due to various factors, including: a long distance to sporting facilities sports facilities not served by public transport and not connected to safe cycle paths lifestyle choice and convenience persistent habits due to lack of awareness and role models. So now it’s time sports organisations turned their collective minds to better understanding the costs and damage caused by CO₂ emissions – and finding solutions.

https://theconversation.com/drive-to-football-take-your-kids-to-the...

Comment by Dr. Krishna Kumari Challa on December 24, 2020 at 9:11am

Plastic is blowing in the wind

As the plastic in our oceans breaks up into smaller and smaller bits without breaking down chemically, the resulting microplastics are becoming a serious ecological problem. A new study at the Weizmann Institute of Science reveals a troubling aspect of microplastics—defined as particles smaller than 5 mm across. They are swept up into the atmosphere and carried on the wind to far-flung parts of the ocean, including those that appear to be clear. Analysis reveals that such minuscule fragments can stay airborne for hours or days, spreading the potential to harm the marine environment and, by climbing up the food chain, to affect human health.

A handful of studies have found microplastics in the atmosphere right above the water near shorelines.

 Trainic, M., Flores, J.M., Pinkas, I. et al. Airborne microplastic particles detected in the remote marine atmosphere. Commun Earth Environ 1, 64 (2020). doi.org/10.1038/s43247-020-00061-

https://phys.org/news/2020-12-plastic.html?utm_source=nwletter&...

Comment by Dr. Krishna Kumari Challa on December 24, 2020 at 9:00am

** Highest levels of microplastics found in molluscs, new study says

Mussels, oysters and scallops have the highest levels of microplastic contamination among seafood, a new study reveals.

The research looked at more than 50 studies between 2014 and 2020 to investigate the levels of microplastic contamination globally in fish and shellfish.

Scientists are still trying to understand the health implications for humans consuming fish and shellfish contaminated with these tiny particles of waste plastic, which finds its ways into waterways and oceans through waste mismanagement.

The paper, "Microplastic contamination of seafood intended for human consumption: a systematic review and meta-analysis" is published in Environmental Health Perspectives.

Research reveals microplastic content levels in seafood

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Journal information: Environmental Health Perspectives 

https://phys.org/news/2020-12-highest-microplastics-molluscs.html?u...

Comment by Dr. Krishna Kumari Challa on December 24, 2020 at 8:55am

Research team reports new class of antibiotics active against a wide range of bacteria

 Scientists have discovered a new class of compounds that uniquely combine direct antibiotic killing of pan drug-resistant bacterial pathogens with a simultaneous rapid immune response for combatting antimicrobial resistance (AMR).

Existing antibiotics target essential bacterial functions, including nucleic acid and protein synthesis, building of the cell membrane, and metabolic pathways. However, bacteria can acquire drug resistance by mutating the bacterial target the antibiotic is directed against, inactivating the drugs or pumping them out.

However, harnessing the immune system to simultaneously attack bacteria on two different fronts makes it hard for them to develop resistance. 

So researchers focused on a metabolic pathway that is essential for most bacteria but absent in humans, making it an ideal target for antibiotic development. This pathway, called methyl-D-erythritol phosphate (MEP) or non-mevalonate pathway, is responsible for biosynthesis of isoprenoids—molecules required for cell survival in most pathogenic bacteria. The lab targeted the IspH enzyme, an essential enzyme in isoprenoid biosynthesis, as a way to block this pathway and kill the microbes. Given the broad presence of IspH in the bacterial world, this approach may target a wide range of bacteria.

Researchers used computer modeling to screen several million commercially available compounds for their ability to bind with the enzyme, and selected the most potent ones that inhibited IspH function as starting points for drug discovery.

The team demonstrated that the IspH inhibitors stimulated the immune system with more potent bacterial killing activity and specificity than current best-in-class antibiotics when tested in vitro on clinical isolates of antibiotic-resistant bacteria, including a wide range of pathogenic gram negative and gram positive bacteria. In preclinical models of gram negative bacterial infection, the bactericidal effects of the IspH inhibitors outperformed traditional pan antibiotics. All compounds tested were shown to be nontoxic to human cells.

IspH inhibitors kill Gram-negative bacteria and mobilize immune clearance, Nature (2020). DOI: 10.1038/s41586-020-03074-x , www.nature.com/articles/s41586-020-03074-x

https://medicalxpress.com/news/2020-12-team-class-antibiotics-wide-...

Comment by Dr. Krishna Kumari Challa on December 23, 2020 at 10:26am

We Just Got Closer to Smartphone Screens That Can 'Heal' Their Own Cracks

Dropping your smartphone often means living with a cracked screen until your next upgrade, or footing an expensive repair bill – but researchers have been busy bringing self-healing display technology closer to a practical reality.

A team from the Korea Institute of Science and Technology (KIST) has developed a self-healing electronic material that can repair its own cracks and other physical damage, and it has one secret ingredient: linseed oil.

Linseed oil is made from flax plant seeds, and these same seeds were adapted by the researchers in a similar way in order to add them to colourless polyimide (CPI) – an alternative to glass that's already finding uses in folding smartphone screens.

That added oil ingredient is able to seep into cracks made when the CPI is fractured, and – if the scientists are able to get it working reliably at scale, could mean screens that are able to bandage their own wounds after a smash.

Researchers were able to develop a self-healing, colourless polyimide that can radically solve the physical properties and lifespan of damaged polymer materials.

The linseed oil that aids this self-healing was first loaded into microcapsules which were then mixed with a silicone material. That material was then used as a coating on top of CPI in the experiments the researchers ran.

The way that the material is designed means that breaks in the CPI also lead to breaks in the microcapsules, releasing the stored oil to repair the damage. When the oil substance hits the air, it hardens, and the material is almost as good as new.

Even better, this all works at room temperature and without the need for external pressure, unlike similar self-healing materials that have been explored before. Higher temperatures, greater humidity and ultraviolet light can speed up the healing process, the researchers report.

https://www.sciencedirect.com/science/article/abs/pii/S135983682033...

https://www.sciencealert.com/we-re-another-step-towards-smartphone-...

Comment by Dr. Krishna Kumari Challa on December 23, 2020 at 10:16am

How Does SpaceX Build Their Rockets

Comment by Dr. Krishna Kumari Challa on December 23, 2020 at 10:08am

Scientists invent glue activated by magnetic field

Scientists from Nanyang Technological University, Singapore (NTU Singapore), have developed a new way to cure adhesives using a magnetic field.

Conventional adhesives like epoxy which are used to bond plastic, ceramics and wood are typically designed to cure using moisture, heat or light. They often require specific curing temperatures, ranging from room temperature up to 80 degrees Celsius.

The curing process is necessary to cross-link and bond the glue with the two secured surfaces as the glue crystallizes and hardens to achieve its final strength.

NTU's new 'magnetocuring' glue can cure by passing it through a magnetic field. This is very useful in certain environmental conditions where current adhesives do not work well. Also, when the adhesive is sandwiched between insulating material like rubber or wood, traditional activators like heat, light and air cannot easily reach the adhesive.

The new adhesive is made of two main components—a commercially available epoxy that is cured through heat, and oxide nanoparticles made from a chemical combination including manganese, zinc and iron (MnxZn_1-xFe₂O₄).

These nanoparticles are designed to heat up when electromagnetic energy is passed through them, activating the curing process. The maximum temperature and rate of heating can be controlled by these special nanoparticles, eliminating overheating and hotspot formation.

Richa Chaudhary et al, Magnetocuring of temperature failsafe epoxy adhesives, Applied Materials Today (2020). DOI: 10.1016/j.apmt.2020.100824

https://phys.org/news/2020-12-scientists-magnetic-field.html?utm_so...

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