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Archive for the ‘biological’ category: Page 57

Aug 10, 2023

Small-molecule autocatalysis may have paved the way for the emergence of evolution by natural selection

Posted by in categories: biological, chemistry, evolution, genetics

The discipline of systems chemistry deals with the analysis and synthesis of various autocatalytic systems and is therefore closely related to the study of the origin of life, since it investigates systems that can be considered as a transition between chemical and biological evolution: more complex than simple molecules, but simpler than living cells.

Tibor Gánti described the theory of self-replicating microspheres as early as 1978. These still lacked , but concealed within their membranes an autocatalytic metabolic network of small molecules, isolated (compartmentalized) within their membranes.

As the autocatalytic process takes place, the membrane-building material is also produced, leading to the division of the sphere. This system may appear to be a , and although it lacks genetic material, this can only be verified experimentally. These microspheres can be considered as “infrabiological” , since they do not reach the level of biological organization, but they exceed the complexity of normal chemical reactions.

Aug 7, 2023

Single-particle photoacoustic vibrational spectroscopy using optical microresonators

Posted by in categories: biological, chemistry, particle physics

Pythagoras first discovered that the vibrations of strings are drastically enhanced at certain frequencies. This discovery forms the basis of our tone system. Such natural vibrations ubiquitously exist in objects regardless of their size scales and are widely utilized to derive their species, constituents, and morphology. For example, molecular vibrations at a terahertz rate have become the most common fingerprints for the identification of chemicals and the structural analysis of large biomolecules.

Recently, natural vibrations of particles at the mesoscopic scale have received growing interest, since this category includes a wide range of functional particles, as well as most and viruses. However, natural vibrations of these mesoscopic particles have remained hidden from existing technologies.

These particles with sizes ranging from 100 nm to 100 μm are expected to vibrate faintly at megahertz to gigahertz rates. This frequency regime could not be resolved by current Raman and Brillouin spectroscopies, however, due to strong Rayleigh-wing scattering, while the performances of piezoelectric techniques that are widely exploited in macroscopic systems degrade significantly at frequencies beyond a few megahertz.

Aug 5, 2023

Turtles Use Earth’s Magnetic Fields And “Quantum Biology” To Get Their Bearings

Posted by in categories: biological, food, quantum physics

Turtles migrate thousands of miles out in the open ocean, charting epic courses in search of food, mates, and nesting grounds. Exactly how they find where they’re going has long puzzled scientists who suspected magnetic fields were involved, but were unsure of the exact mechanism through which turtles were sensing it.

We’ve since learned that turtles appear to recognize magnetic signatures of locations, such as the beach on which they hatched where females will later return to lay their own eggs. We know the magnetosphere is in constant flux, and turtle nesting sites have been found to shift in tandem, so how is it that they’re able to make sense of this invisible force?

Some answers to this question were revealed in a study that looked at the way snapping turtles can tell north from south, in a phenomenon known as spontaneous magnetic alignment. It was once thought to be a rare trait in the animal kingdom, but as Professor John Phillips from the Department of Biological Sciences at Virginia Tech told IFLScience, this is no longer the case.

Aug 5, 2023

CDC detects coronavirus, HIV, hepatitis and herpes at unlicensed California lab

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

Local and federal authorities spent months investigating a warehouse in Fresno County, California, that they suspect was home to an illegal, unlicensed laboratory full of lab mice, medical waste and hazardous materials.

The Fresno County Public Health Department has been “evaluating and assessing the activities of an unlicensed laboratory” in Reedley, the health department’s assistant director, Joe Prado, said in a statement Thursday. All of the biological agents were destroyed by July 7 following a legal abatement process by the agency.

“The evaluation required coordination and collaboration with multiple federal and state agencies to determine and classify biological and chemical contents onsite, in addition to assessing jurisdictional authority under this unique situation,” Prado said.

Aug 5, 2023

Dr. Joshua Tewksbury, Ph.D. — Director, Smithsonian Tropical Research Institute (STRI)

Posted by in categories: biological, climatology, education, sustainability

Is the Ira Rubinoff Director of the Smithsonian Tropical Research Institute (STRI https://www.si.edu/about/bios/joshua-tewksbury), part of the Smithsonian Institution, the world’s largest museum, education, and research complex. He oversees more than 400 employees, with an annual budget of $35 million. Headquartered in Panama City, Panama, with field sites around the world, STRI furthers the understanding and public awareness of tropical biodiversity and its importance to human welfare. In addition to its resident scientists and support staff, STRI’s facilities are used annually by some 1,400 visiting scientists, pre-and postdoctoral fellows and interns from around the world.

Dr. Tewksbury is an ecologist with more than two decades of research in conservation and biodiversity, as well as nearly a decade of executive leadership experience at international research institutes.

Continue reading “Dr. Joshua Tewksbury, Ph.D. — Director, Smithsonian Tropical Research Institute (STRI)” »

Aug 5, 2023

Exploring the self-organizing origins of life

Posted by in category: biological

Catalytic molecules can form metabolically active clusters by creating and following concentration gradients—this is the result of a new study by scientists from the Max Planck Institute for Dynamics and Self-Organization (MPI-DS). Their model predicts the self-organization of molecules involved in metabolic pathways, adding a possible new mechanism to the theory of the origin of life.

The results can help to better understand how participating in complex biological networks can form dynamic functional structures, and provide a platform for experiments on the origins of life.

One possible scenario for the is the spontaneous organization of interacting molecules into cell-like droplets. These molecular would form the first self-replicating metabolic cycles, which are ubiquitous in biology and common throughout all organisms. According to this paradigm, the first biomolecules would need to together through slow and overall inefficient processes.

Aug 2, 2023

Quantum-enhanced non-interferometric quantitative phase imaging

Posted by in categories: biological, nanotechnology, quantum physics

Optical phase retrieval and imaging appear in a wide variety of science fields, such as imaging of quasi-transparent biological samples or nanostructures metrological characterization, for example, in the semiconductor industry. At a fundamental level, the limit to imaging accuracy in classical systems comes from the intrinsic fluctuation of the illuminating light, since the photons that form it are emitted randomly by conventional sources and behave independently of one another.

Quantum correlation in light beams, in which photons show certain cooperation, can surpass those limits. Although obtained in phase estimation through first-order interference is well understood, interferometric schemes are not suitable for multi-parameter wide-field imaging, requiring raster scanning for extended samples.

In a new paper published in Light Science & Application, a team of scientists from the Quantum Optics Group of the Italian National Metrology Institute (INRiM), Italy, and from the Imaging Physics Dept. Optics Research Group, Faculty of Applied Sciences of Delft University of Technology, The Netherlands, has developed a technology exploiting quantum correlations to enhance imaging of phase profiles in a non-interferometric way.

Jul 31, 2023

Axolotl: The adorable amphibian that can regrow its body and stay looking young forever

Posted by in category: biological

The Mexican salamander is only found in two lakes and is considered critically endangered, with pollution and invasive predators driving the species’ decline.

Jul 30, 2023

Scientists unveil synergistic method for non-canonical amino acid synthesis

Posted by in categories: biological, chemistry

New chemistry, new enzymology. With a new method that merges the best of two worlds—the unique and complementary activities of enzymes and small-molecule photochemistry—researchers at UC Santa Barbara have opened the door to new catalytic reactions. Their synergistic method allows for new products and can streamline existing processes, in particular, the synthesis of non-canonical amino acids, which are important for therapeutic purposes.

“This method solves what in my opinion is one of the most important problems in our field: how to develop new catalytic reactions in a general sense that are new to both biology and chemistry,” said chemistry Professor Yang Yang, an author of a paper that appears in the journal Science. “On top of that, the process is stereoselective, meaning it can select for a preferred “shape” of the resulting amino .”

The synergistic photobiocatalytic method consists of two co-occurring catalytic reactions. The photochemical reaction generates a short-lived intermediate molecule that works with the reactive intermediate of the enzymatic process, resulting in the amino acid.

Jul 29, 2023

Robert Sapolsky: Justice and morality in the absence of free will | Full [Vert Dider] 2020

Posted by in categories: biological, neuroscience

In September 2020 we sat down with Robert Sapolsky, Stanford professor and the author of Human Behavioral Biology lectures (https://youtu.be/NNnIGh9g6fA) to discuss if it’s possible for our society to reconcile our understanding of justice with scientific understanding of human behaviour.

Why do humans, most likely, have no free will? How does that link to depression and other psychiatric disorders? Can people accept the idea that there is no free will and start using, what science tells us about the reasons behind our behaviour, as a basis for making sense of justice and morality? If yes, can we even imagine what such society would look like?

Continue reading “Robert Sapolsky: Justice and morality in the absence of free will | Full [Vert Dider] 2020” »

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