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Archive for the ‘chemistry’ category: Page 286

May 15, 2020

MIT Nanosensor Can Alert a Smartphone When Plants Are Stressed

Posted by in categories: chemistry, mobile phones, nanotechnology

Carbon nanotubes embedded in leaves detect chemical signals that are produced when a plant is damaged.

MIT engineers have developed a way to closely track how plants respond to stresses such as injury, infection, and light damage, using sensors made of carbon nanotubes. These sensors can be embedded in plant leaves, where they report on hydrogen peroxide signaling waves.

Plants use hydrogen peroxide to communicate within their leaves, sending out a distress signal that stimulates leaf cells to produce compounds that will help them repair damage or fend off predators such as insects. The new sensors can use these hydrogen peroxide signals to distinguish between different types of stress, as well as between different species of plants.

May 15, 2020

Researchers develop an artificial chloroplast

Posted by in categories: biotech/medical, chemistry, food, nanotechnology

Over billions of years, microorganisms and plants evolved the remarkable process we know as photosynthesis. Photosynthesis converts sun energy into chemical energy, thus providing all life on Earth with food and oxygen. The cellular compartments housing the molecular machines, the chloroplasts, are probably the most important natural engines on earth. Many scientists consider artificially rebuilding and controlling the photosynthetic process the “Apollo project of our time.” It would mean the ability to produce clean energy—clean fuel, clean carbon compounds such as antibiotics, and other products simply from light and carbon dioxide.

But how to build a living, photosynthetic cell from scratch? Key to mimicking the processes of a living cell is to get its components to work together at the right time and place. At the Max Planck Society, this ambitious goal is pursued in an interdisciplinary multi-lab initiative, the MaxSynBio network. Now the Marburg research team led by director Tobias Erb has succeeded successfully created a platform for the automated construction of cell-sized photosynthetically active compartments, “artificial chloroplasts,” that are able to capture and convert the greenhouse gas dioxide with light.

May 14, 2020

Scientists say doing this type of exercise will make your brain more powerful

Posted by in categories: chemistry, health, neuroscience

According to Li and Spitzer, running on a treadmill, or performing another sustained aerobic exercise—like dancing or kickboxing—on a regular basis might actually enhance motor skill-based learning.

When comparing the brains of mice that exercised versus those who did not, Li and Spitzer found that specific neurons switched their chemical signals (neurotransmitters), after exercising, which led to improved learning for motor skill-specific acquisition.

While physical exercise is proven to promote motor skill learning in normal individuals as well as those with neurological disorders, the mechanism of action is unclear. The study found that that one just week of voluntary wheel running enhances the acquisition of motor skills in normal adult mice. Voluntary being the keyword here.

May 14, 2020

A new, highly sensitive chemical sensor uses protein nanowires

Posted by in categories: biotech/medical, chemistry, engineering, food, health, nanotechnology

Writing in the journal NanoResearch, a team at the University of Massachusetts Amherst reports this week that they have developed bioelectronic ammonia gas sensors that are among the most sensitive ever made.

The sensor uses electric-charge-conducting protein derived from the bacterium Geobacter to provide biomaterials for electrical devices. More than 30 years ago, senior author and microbiologist Derek Lovley discovered Geobacter in river mud. The microbes grow hair-like protein filaments that work as nanoscale “wires” to transfer charges for their nourishment and to communicate with other bacteria.

First author and doctoral student Alexander Smith, with his advisor Jun Yao and Lovley, say they designed this first sensor to measure ammonia because that gas is important to agriculture, the environment and biomedicine. For example, in humans, ammonia on the breath may signal disease, while in poultry farming, the gas must be closely monitored and controlled for bird health and comfort and to avoid feed imbalances and production losses.

May 12, 2020

Nanofiber membranes transformed into 3D scaffolds

Posted by in categories: biotech/medical, chemistry, robotics/AI

In the movie “Transformers,” cars morph into robots, jets or a variety of machinery. A similar concept inspired a group of researchers to combine gas foaming, which is a blend of chemicals that induces gas bubbling, and 3D molding technologies to quickly transform electrospun membranes into complex 3D shapes for biomedical applications.

In Applied Physics Reviews, the group reports on its new approach that demonstrates significant improvements in speed and quality compared with other methods. The work is also the first successful demonstration of formation of 3D neural constructs with an ordered structure through differentiation of human neural progenitor/ on these transformed 3D scaffolds.

“Electrospinning is a technology to produce nanofiber membranes,” said co-author Jingwei Xie, at the University of Nebraska Medical Center. “The physics principle behind it involves applying an electrical force to overcome the surface tension of a solution to elongate a solution jet into continuous and ultrafine fibers after solvent evaporation.”

May 12, 2020

Epigenetic changes during aging and their reprogramming potential

Posted by in categories: biotech/medical, chemistry, genetics, life extension

If you are interested in age reversal, and you haven’t read Dr David Sinclair (Harvard Medical School) yet, then I’d recommend this research paper.

“Excitingly, new studies show that age-related epigenetic changes can be reversed with interventions such as cyclic expression of the Yamanaka reprogramming factors. This review presents a summary of epigenetic changes that occur in aging, highlights studies indicating that epigenetic changes may contribute to the aging process and outlines the current state of research into interventions to reprogram age-related epigenetic changes.”


The aging process results in significant epigenetic changes at all levels of chromatin and DNA organization. These include reduced global heterochromatin, nucleosome remodeling and loss, changes in histone marks, global DNA hypomethylation with CpG island hypermethylation, and the relocalization of chromatin modifying factors. Exactly how and why these changes occur is not fully understood, but evidence that these epigenetic changes affect longevity and may cause aging, is growing. Excitingly, new studies show that age-related epigenetic changes can be reversed with interventions such as cyclic expression of the Yamanaka reprogramming factors. This review presents a summary of epigenetic changes that occur in aging, highlights studies indicating that epigenetic changes may contribute to the aging process and outlines the current state of research into interventions to reprogram age-related epigenetic changes.

Continue reading “Epigenetic changes during aging and their reprogramming potential” »

May 11, 2020

Electromagnetic water cloak eliminates drag and wake

Posted by in categories: chemistry, particle physics

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object’s wake, greatly reducing its drag while simultaneously helping it avoid detection.

The idea originated at Duke University in 2011 when researchers outlined the general concept. By matching the acceleration of the surrounding water to an ’s movement, it would theoretically be possible to greatly increase its propulsion efficiency while leaving the surrounding sea undisturbed. The theory was an extension of the group’s pioneering work in metamaterials, where a material’s structure, rather than its chemistry, creates desired properties.

Six years later, Yaroslav Urzhumov, adjunct assistant professor of electrical and computer engineering at Duke, has updated the theory by detailing a potential approach. But rather than using a complex system of very small pumps as originally speculated, Urzhumov is turning to electromagnetic fields and the dense concentration of charged particles found in saltwater.

May 11, 2020

Revealed: Plants Molecular ‘Alarm’ System That Protects Them From Predators

Posted by in categories: chemistry, military

Scientists uncover how oral secretions of the cotton leaf worm trigger defense responses in a plant.

In nature, every species must be equipped with a strategy to be able to survive in response to danger. Plants, too, have innate systems that are triggered in response to a particular threat, such as insects feeding on them.

For example, some plants sense “herbivore-derived danger signals” (HDS), which are specific chemicals in oral secretions of insects. This activates a cascade of events in the plant’s defense machinery, which leads to the plant developing “resistance” to (or “immunity” against) the predator. But despite decades of research, exactly how plants recognize these signals has remained a bit of a mystery.

May 10, 2020

Reversing age: dual species measurement of epigenetic age with a single clock

Posted by in categories: biotech/medical, chemistry, finance, genetics, life extension, neuroscience

Young blood plasma is known to confer beneficial effects on various organs in mice. However, it was not known whether young plasma rejuvenates cells and tissues at the epigenetic level; whether it alters the epigenetic clock, which is a highly-accurate molecular biomarker of aging. To address this question, we developed and validated six different epigenetic clocks for rat tissues that are based on DNA methylation values derived from n=593 tissue samples. As indicated by their respective names, the rat pan-tissue clock can be applied to DNA methylation profiles from all rat tissues, while the rat brain-, liver-, and blood clocks apply to the corresponding tissue types. We also developed two epigenetic clocks that apply to both human and rat tissues by adding n=850 human tissue samples to the training data. We employed these six clocks to investigate the rejuvenation effects of a plasma fraction treatment in different rat tissues. The treatment more than halved the epigenetic ages of blood, heart, and liver tissue. A less pronounced, but statistically significant, rejuvenation effect could be observed in the hypothalamus. The treatment was accompanied by progressive improvement in the function of these organs as ascertained through numerous biochemical/physiological biomarkers and behavioral responses to assess cognitive functions. Cellular senescence, which is not associated with epigenetic aging, was also considerably reduced in vital organs. Overall, this study demonstrates that a plasma-derived treatment markedly reverses aging according to epigenetic clocks and benchmark biomarkers of aging.

Several authors are founders, owners, employees (Harold Katcher and Akshay Sanghavi) or consultants of Nugenics Research (Steve Horvath and Agnivesh Shrivastava) which plans to commercialize the “Elixir” treatment. Other authors (Kavita Singh, Shraddha Khairnar) received financial support from Nugenics Research. The other authors do not have conflict of interest.

May 8, 2020

Chemistry breakthrough could speed up drug development

Posted by in categories: biotech/medical, chemistry, nanotechnology

Scientists have successfully developed a new technique to reliably grow crystals of organic soluble molecules from nanoscale droplets, unlocking the potential of accelerated new drug development.

Chemistry experts from Newcastle and Durham universities, working in collaboration with SPT Labtech, have grown the small crystals from nanoscale encapsulated droplets. Their innovative method, involving the use of inert oils to control evaporative solvent loss, has the potential to enhance the development pipeline.

Whilst crystallization of organic soluble is a technique used by scientists all over the world, the ability to do so with such small quantities of analyte is ground-breaking.