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A change in just one letter in the code that makes up a cancer-causing gene can significantly affect how aggressive a tumor is or how well a patient with cancer responds to a particular therapy. A new, very precise gene-editing tool created by Weill Cornell Medicine investigators will enable scientists to study the impact of these specific genetic changes in preclinical models rather than being limited to more broadly targeted tactics, such as deleting the entire gene.

The tool was described in a study published Aug. 10 in Nature Biotechnology. Dr. Lukas Dow, an associate professor of biochemistry in medicine at Weill Cornell Medicine, and his colleagues genetically engineered mice to carry an enzyme that allows the scientists to change a single base or “letter” in the mouse’s genetic code. The enzyme can be turned on or off by feeding the mice an antibiotic called doxycycline, reducing the prospect of unintended genetic changes occurring over time. The tool can also grow miniature versions of intestine, lung, and pancreas tissue called organoids from the mice, enabling even more molecular and biochemical studies of the impact of these precise genetic changes.

“We are excited about using this technology to try and understand the genetic changes that influence a patient’s response to cancer therapies,” said Dr. Dow, who is also a member of the Sandra and Edward Meyer Cancer Center at Weill Cornell Medicine.

Multiple complementary DNA strands can be thermally annealed into desired entities to engineer DNA nanostructures. In a new study now published in Nature Nanotechnology, Caroline Rossi-Gendron and a team of researchers in chemistry, materials science and biology in France and Japan used a magnesium-free buffer containing sodium chloride, complex cocktails of DNA strands and proteins to self-assemble isothermally at room temperature or physiological temperature into user-defined nanostructures including nanogrids, DNA origami and single-stranded tile assemblies.

This self-assembly relied on thermodynamics, proceeding through multiple folding pathways to create highly configurable nanostructures. The method allowed the self-selection of the most stable shape in a large pool of competitive DNA strands. Interestingly, DNA origami can shift isothermally from an initially stable shape to a radically different one through an exchange of constitutive staple strands. This expanded the collection of shapes and functions obtained via isothermal self-assembly to create the foundation for adaptive nanomachines and facilitate evolutionary nanostructure discovery.

Self-assembly occurs when naturally occurring or rationally designed entities can embed necessary information to spontaneously interact and self-organize into functional superstructures of interest. Typically, synthetic self-assembled materials result from the organization of a repeating single component to create a stable supramolecular assembly containing micelles or colloidal crystals with a prescribed set of useful properties. Such constructs have limited reconfigurability, making it highly challenging to produce the desired structures.

Researchers have long thought that rewards like food or money encourage learning in the brain by causing the release of the “feel-good” hormone dopamine, known to reinforce storage of new information. Now, a new study in rodents describes how learning still occurs in the absence of an immediate incentive.

Led by researchers at NYU Grossman School of Medicine, the study explored the relationship between dopamine and the brain chemical acetylcholine, also known to play a role in learning and memory. Past research had shown that these two hormones compete with one another, so that a boost in one causes a decline in the other. Rewards were thought to promote learning by simultaneously triggering an increase in dopamine and a decrease in acetylcholine.

This sudden hormone imbalance is believed to open a window of opportunity for brain cells to adjust to new circumstances and form memories for later use. Known as neuroplasticity, this process is a major feature of learning as well as recovery after injury. However, the question had remained whether food and other external rewards are the only drivers for this memory system, or whether our brains instead are able to create the same conditions that are favorable to learning without outside help.

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 genetic material, 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 living cell, and although it lacks genetic material, this can only be verified experimentally. These microspheres can be considered as “infrabiological” chemical systems, since they do not reach the level of biological organization, but they exceed the complexity of normal chemical reactions.

A team from the University of Chicago.

Founded in 1,890, the University of Chicago (UChicago, U of C, or Chicago) is a private research university in Chicago, Illinois. Located on a 217-acre campus in Chicago’s Hyde Park neighborhood, near Lake Michigan, the school holds top-ten positions in various national and international rankings. UChicago is also well known for its professional schools: Pritzker School of Medicine, Booth School of Business, Law School, School of Social Service Administration, Harris School of Public Policy Studies, Divinity School and the Graham School of Continuing Liberal and Professional Studies, and Pritzker School of Molecular Engineering.

A key aspect of how the brain learns and enables decision-making processes is through synaptic interactions. Electrical transmission and communication in a network of synapses are modulated by extracellular fields generated by ionic chemical gradients. Emulating such spatial interactions in synthetic networks can be of potential use for neuromorphic learning and the hardware implementation of artificial intelligence. Here, we demonstrate that in a network of hydrogen-doped perovskite nickelate devices, electric bias across a single junction can tune the coupling strength between the neighboring cells. Electrical transport measurements and spatially resolved diffraction and nanoprobe X-ray and scanning microwave impedance spectroscopic studies suggest that graded proton distribution in the inhomogeneous medium of hydrogen-doped nickelate film enables this behavior.

Deep space is a hostile environment for humans, which makes the long journey to Mars a serious stumbling block for manned missions. A nuclear-powered rocket could slash the journey time, and NASA has announced plans to test the technology by 2027 at the latest.

Most spacecraft to date have used chemical rockets packed with fuel and oxidizer, which rely on combustion to propel them through space. A nuclear-powered rocket would instead use a fission reactor to heat liquid hydrogen to very high temperatures and then blast it out the back of the spacecraft.

These kinds of engines could be up to three times more efficient than those in conventional rockets, and could cut the time to transit from Earth to Mars from roughly seven months to as little as six weeks. NASA has teamed up with DARPA to make the idea a reality, signing a deal with defense contractor Lockheed Martin to launch a working prototype into space as early as 2025.

Weird things happen on the quantum level. Whole clouds of particles can become entangled, their individuality lost as they act as one.

Now scientists have observed, for the first time, ultracold atoms cooled to a quantum state chemically reacting as a collective, rather than haphazardly forming new molecules after bumping into each other by chance.

“What we saw lined up with the theoretical predictions,” says Cheng Chin, a physicist at the University of Chicago and senior author of the study. “This has been a scientific goal for 20 years, so it’s a very exciting era.”

“This has been a scientific goal for 20 years, so it’s a very exciting era.”

In a significant advance, scientists have obtained the first proof of a phenomenon known as “quantum superchemistry.” This effect was previously predicted but never actually observed in the laboratory.

The University of Chicago researchers that led this experiment characterize quantum superchemistry as a “phenomenon where particles in the same quantum state undergo collectively accelerated reactions.”

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