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Archive for the ‘biological’ category: Page 142

Aug 15, 2020

To understand the machinery of life, this scientist breaks it on purpose

Posted by in categories: biological, genetics

“We expected that the hammer of natural selection also comes down randomly, but that is not what we found,” he said. “Rather, it does not act randomly but has a strong bias, favoring those mutations that provide the largest fitness advantage while it smashes down other less beneficial mutations, even though they also provide a benefit to the organism.”

In other words, evolution is not a multitasker when it comes to fixing problems.

“It seems that evolution is myopic,” Venkataram said. “It focuses on the most immediate problem, puts a Band-Aid on and then it moves on to the next problem, without thoroughly finishing the problem it was working on before.”

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Aug 14, 2020

Exponential scaling of frictional forces in cells

Posted by in categories: biological, chemistry

AMOLF researchers have presented a theory that describes the friction between biological filaments that are crosslinked by proteins. Surprisingly, their theory predicts that the friction force scales highly nonlinearly with the number of crosslinkers. The authors believe that cells use this scaling not only to stabilize cellular structures, but also to control their size. The new findings are important for the understanding of the dynamics of cellular structures such as the mitotic spindle, which pulls chromosomes apart during cell division.

Motor proteins versus frictional forces

Many consist of long filaments that are crosslinked by motor proteins and non-motor proteins (see figure). These so-called cytoskeletal structures not only give cells their mechanical stability, but also enable them to crawl over surfaces and to pull chromosome apart during . Force generation is typically attributed to motor proteins, which, using chemical fuel, can move the filaments with respect to one another. However, these motor forces are opposed by frictional forces that are generated by passive, non–. These frictional forces are a central determinant of the mechanical properties of cytoskeletal structures, and they limit the speed and efficiency with which these structures are formed. Moreover, they can even be vital for their stability, because if the motor forces are not opposed by the forces generated by the passive crosslinkers, the structures can even fall apart.

Aug 8, 2020

Omniviolence Is Coming and the World Isn’t Ready

Posted by in categories: bioengineering, biological, cybercrime/malcode, drones, internet, law enforcement, nanotechnology, robotics/AI

The terrorist or psychopath of the future, however, will have not just the Internet or drones—called “slaughterbots” in this video from the Future of Life Institute—but also synthetic biology, nanotechnology, and advanced AI systems at their disposal. These tools make wreaking havoc across international borders trivial, which raises the question: Will emerging technologies make the state system obsolete? It’s hard to see why not. What justifies the existence of the state, English philosopher Thomas Hobbes argued, is a “social contract.” People give up certain freedoms in exchange for state-provided security, whereby the state acts as a neutral “referee” that can intervene when people get into disputes, punish people who steal and murder, and enforce contracts signed by parties with competing interests.

The trouble is that if anyone anywhere can attack anyone anywhere else, then states will become—and are becoming—unable to satisfy their primary duty as referee.

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Aug 7, 2020

New science behind biodegradable algae-based flip-flops

Posted by in categories: biological, chemistry, science, sustainability

As the world’s most popular shoe, flip-flops account for a troubling percentage of plastic waste that ends up in landfills, on seashores and in our oceans. Scientists at the University of California San Diego have spent years working to resolve this problem, and now they have taken a step farther toward accomplishing this mission.

Sticking with their chemistry, the team of researchers formulated , made from algae oil, to meet commercial specifications for midsole shoes and the foot-bed of flip-flops. The results of their study are published in Bioresource Technology Reports and describe the team’s successful development of these sustainable, consumer-ready and .

The research was a collaboration between UC San Diego and startup company Algenesis Materials—a and technology company. The project was co-led by graduate student Natasha Gunawan from the labs of professors Michael Burkart (Division of Physical Sciences) and Stephen Mayfield (Division of Biological Sciences), and by Marissa Tessman from Algenesis. It is the latest in a series of recent research publications that collectively, according to Burkart, offer a complete solution to the plastics problem—at least for polyurethanes.

Aug 7, 2020

Oldest enzyme in cellular respiration isolated

Posted by in categories: biological, habitats

In the first billion years, there was no oxygen on Earth. Life developed in an anoxic environment. Early bacteria probably obtained their energy by breaking down various substances by means of fermentation. However, there also seems to have been a kind of “oxygen-free respiration.” This was suggested by studies on primordial microbes that are still found in anoxic habitats today.

“We already saw ten years ago that there are genes in these microbes that perhaps encode for a primordial respiration . Since then, we—as well as other groups worldwide—have attempted to prove the existence of this respiratory enzyme and to isolate it. For a long time unsuccessfully because the complex was too fragile and fell apart at each attempt to isolate it from the membrane. We found the fragments, but were unable to piece them together again,” explains Professor Volker Müller from the Department of Molecular Microbiology and Bioenergetics at Goethe University.

Through hard work and perseverance, his doctoral researchers Martin Kuhns and Dragan Trifunovic then achieved a breakthrough in two successive doctoral theses. “In our desperation, we at some point took a heat-loving bacterium, Thermotoga maritima, which grows at temperatures between 60 and 90°C,” explains Trifunovic, who will shortly complete his doctorate. “Thermotoga also contains Rnf genes, and we hoped that the Rnf enzyme in this bacterium would be a bit more stable. Over the years, we then managed to develop a method for isolating the entire Rnf enzyme from the membrane of these bacteria.”

Aug 6, 2020

Social bonds in adulthood don’t mediate early life trauma

Posted by in categories: biological, health

When baboons experience trauma in early life, they have higher levels of stress hormones in adulthood—a potential marker of poor health—than their peers who don’t experience trauma, even if they have strong social relationships as adults, according to a study led by a University of Michigan researcher.

The study examined the links between childhood adversity, adult social relationships and glucocorticoid concentrations. The goal was to determine whether one of the reasons that baboons who experience early trauma live shorter, less healthy lives was because they fail to develop strong social relationships in adulthood, which could be beneficial to health.

U-M biological anthropologist Stacy Rosenbaum and her co-authors found that while early life adversity didn’t strongly affect baboons’ ability to have social relationships, any positive effect of those relationships was much smaller than the large negative effects of early life trauma.

Aug 5, 2020

Unusual nanoparticles could benefit the quest to build a quantum computer

Posted by in categories: biological, chemistry, climatology, computing, engineering, nanotechnology, quantum physics, sustainability

Imagine tiny crystals that “blink” like fireflies and can convert carbon dioxide, a key cause of climate change, into fuels.

A Rutgers-led team has created ultra-small dioxide crystals that exhibit unusual “blinking” behavior and may help to produce methane and other fuels, according to a study in the journal Angewandte Chemie. The crystals, also known as nanoparticles, stay charged for a long time and could benefit efforts to develop quantum computers.

“Our findings are quite important and intriguing in a number of ways, and more research is needed to understand how these exotic crystals work and to fulfill their potential,” said senior author Tewodros (Teddy) Asefa, a professor in the Department of Chemistry and Chemical Biology in the School of Arts and Sciences at Rutgers University-New Brunswick. He’s also a professor in the Department of Chemical and Biochemical Engineering in the School of Engineering.

Aug 3, 2020

Skrillex — Kill Everybody (Bare Noize Remix)

Posted by in category: biological

MetaRomantism and “Evil”

MetaRomanticism can be thought of as an attempt to reform Romanticism, which seems necessary since it seems to be a constant companion to Modernism and it is especially dangerous when it has access to Modernist tools that is uses while refusing to be rational. Perhaps this explains the horrors of Nazism in the 20th century. Nazis were irrationalist Romantics that stole the Modernist tools of Weimar Germany and nearly destroyed human civilization and they attached themselves to Dharma traditions that sometime support versions of annihilationism.

How can MetaRomanticism help?

Continue reading “Skrillex — Kill Everybody (Bare Noize Remix)” »

Aug 3, 2020

Transcranial Stimulation to Prevent Fear Memories From Returning

Posted by in categories: biological, neuroscience

Summary: Repetitive transcranial memory stimulation applied to the dorsolateral prefrontal cortex modifies the negative effects of fear memories. The findings could have implications for the treatment of PTSD.

Source: University of Bologna

A research group from the University of Bologna has succeeded in modifying the negative effect of a returning memory that triggers fear, and developed a new non-invasive experimental protocol. The result of this study, published in the journal Current Biology, is an innovative protocol that combines fear conditioning—a stimulus associated with something unpleasant that induces a negative memory—and the neurostimulation of a specific site of the prefrontal cortex.

Aug 1, 2020

‘Drawn-on-skin’ electronics offer breakthrough in wearable monitors

Posted by in categories: biological, engineering, health, wearables

A team of researchers led by Cunjiang Yu, Bill D. Cook Associate Professor of Mechanical Engineering at the University of Houston, has developed a new form of electronics known as “drawn-on-skin electronics,” allowing multifunctional sensors and circuits to be drawn on the skin with an ink pen.

The advance, the researchers report in Nature Communications, allows for the collection of more precise, motion artifact-free health data, solving the long-standing problem of collecting precise biological data through a when the subject is in motion.

The imprecision may not be important when your FitBit registers 4,000 steps instead of 4,200, but sensors designed to check heart function, temperature and other physical signals must be accurate if they are to be used for diagnostics and treatment.