Earth
On the DNA assembly line, two proofreading proteins work together as an emergency stop button to prevent replication errors. New research from North Carolina State University and the University of North Carolina at Chapel Hill shows how these proteins - MutL and MutS - prevent DNA replication errors by creating an immobile structure that calls more proteins to the site to repair the error. This structure could also prevent the mismatched region from being "packed" back into the cell during division.
The idea of the cell as a city is a common introduction to biology, conjuring depictions of the cell's organelles as power plants, factories, roads, libraries, warehouses and more. Like a city, these structures require a great deal of resources to build and operate, and when resources are scarce, internal components must be recycled to provide essential building blocks, particularly amino acids, to sustain vital functions.
Viruses are scary. They invade our cells like invisible armies, and each type brings its own strategy of attack. While viruses devastate communities of humans and animals, scientists scramble to fight back. Many utilize electron microscopy, a tool that can "see" what individual molecules in the virus are doing. Yet even the most sophisticated technology requires that the sample be frozen and immobilized to get the highest resolution.
Beavers and wolverines in Northern Alberta are using industry-created borrow pits as homes and feeding grounds, according to a new study by University of Alberta ecologists.
The research examined the relationship between local wildlife and borrow pits, which are industry-created sites where material such as soil, gravel, or sand has been dug up for road construction. The results show that when revegetated the sites provide homes for beavers, which in turn support the survival of wolverines.
Amphibians have few options to avoid the under appreciated one-two punch of climate change, according to a new study from Simon Fraser University researchers and others.
Rising summer temperatures are also resulting in higher rates of dehydration among wet-skinned amphibians as they attempt to keep themselves cool.
Antarctica is considered one of the Earth's largest, most pristine remaining wildernesses. Yet since its formal discovery 200 years ago, the continent has seen accelerating and potentially impactful human activity.
How widespread this activity is across the continent has never been quantified. We know Antarctica has no cities, agriculture or industry. But we have never had a good idea of where humans have been, how much of the continent remains untouched or largely unimpacted, and to what extent these largely unimpacted areas serve to protect biodiversity.
DALLAS, JULY 16, 2020 -- The rate of recurrent strokes significantly declined among Mexican Americans in a long-term study, according to new research published today in Stroke, a journal of the American Stroke Association, a division of the American Heart Association.
Recurrent stroke rates declined faster in Mexican Americans than in non-Hispanics whites. By the end of the study in 2013, the differences between these two groups had vanished. Mexican Americans had a significant reduction in stroke recurrence even though the death rate from stroke remained steady.
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 titanium 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.
Monolayer graphene, an atomic-layer thick sheet of carbon has found immense applications in diverse fields including chemical sensors, detecting single molecule adsorption events electronically. Therefore, monitoring physisorbed molecule induced changes of the electrical response of graphene has become ubiquitous in graphene based sensors. Electric field tuning of the physisorbed molecule-graphene interaction results in enhanced gas sensing due to unique electric field dependent charge-transfer between the adsorbed gas and graphene.
Taking advantages of intramolecular motion of D-A based aggregation-induced emission (AIE) molecular rotors and one-dimensional (1D) polymer fibers, highly sensitive optical fiber sensors that respond to ambient humidity rapidly and reversibly with observable chromatic fluorescence change are developed. Moisture environments induce the swelling of the polymer fibers, activating intramolecular motions of AIE molecules to result in red-shifted fluorescence and linear response to ambient relative humidity (RH).
Some dog breeds have higher risk of developing certain cancers and joint disorders if neutered or spayed within their first year of life. Until now, studies had only assessed that risk in a few breeds. A new, 10-year study by researchers at the University of California, Davis, examined 35 dog breeds and found vulnerability from neutering varies greatly depending on the breed. The study was published in the journal Frontiers in Veterinary Science.
Reprogramming of immune cells enhances effects of radiotherapy in preclinical models of brain cancer
JULY 15, 2020, NEW YORK-- A Ludwig Cancer Research study has dissected how radiotherapy alters the behavior of immune cells known as macrophages found in glioblastoma (GBM) tumors and shown how these cells might be reprogrammed with an existing drug to suppress the invariable recurrence of the aggressive brain cancer.
An international research group led by Chiba University Professor Shiki Yagai has for the first time succeeded in forming self-assembled "polycatenanes," which are structures comprised of mechanically interlocked small molecule rings. The research group also succeeded in observing the geometric structure of the polycatenanes by using atomic force microscopy (AFM). This work, published in the journal Nature, is the first to achieve synthesis of nano-polycatenanes through molecular self-assembly without using additional molecular templates.
The development of the mammalian placenta depends upon an unusual twist that separates DNA's classic double helix into a single-stranded form, Yale researchers report July 15 in the journal Nature.
The Yale team also identified the molecular regulator that acts upon this single strand to accelerate or stop placental development, a discovery with implications not only for diseases of pregnancy but also for understanding how cancer tumors proliferate.
New research from Arizona State and Stanford Universities is augmenting meteorological studies that predict global warming trends and heat waves, adding human originated factors into the equation.
The process quantifies the changing statistics of temperature evolution before global warming in the early 20th century and recent heat wave events to serve as the early warning signals for potential catastrophic changes. In addition, the study illustrates the contrast between urban and rural early warning signals for extreme heat waves.