Diseases, Conditions, Syndromes

Breakthrough on diarrhea virus opens up for new vaccines

Researchers at Umeå University in Sweden have for the first time at the atomic level succeeded in mapping what a virus looks like that causes diarrhea and annually kills about 50,000 children in the world. The discovery ...

Medical research

Two molecular handshakes for hearing

We hear sounds in part because tiny filaments inside our inner ears help convert voices, music and noises into electrical signals that are sent to our brains for processing. Now, scientists have mapped and simulated those ...

Dentistry

Complexity of human tooth enamel revealed at atomic level

Scientists used a combination of advanced microscopy and chemical detection techniques to uncover the structural makeup of human tooth enamel at unprecedented atomic resolution, revealing lattice patterns and unexpected irregularities. ...

Health

What the brain really thinks about forever chemicals

The human-made chemicals that make our kitchen pans stick-free, our athletic wear water-repellent and firefighting chemicals more efficient do their jobs incredibly well, but it's at the expense of lingering in the body and ...

Neuroscience

Molecular bodyguards against Parkinson's disease

Chaperone proteins in human cells dynamically interact with the protein α-Synuclein, which is strongly associated with Parkinson's disease. A disturbed relationship to these "bodyguards" leads to cell damage and the formation ...

Immunology

Early immune response may improve cancer immunotherapies

In a paper published in the Journal of Biological Chemistry, University of Illinois at Chicago researchers and colleagues report a new mechanism for detecting foreign material during early immune responses.

Medical research

Skeletal imitation reveals how bones grow atom-by-atom

Researchers from Chalmers University of Technology, Sweden, have discovered how our bones grow at an atomic level, showing how an unstructured mass orders itself into a perfectly arranged bone structure. The discovery offers ...

Diseases, Conditions, Syndromes

Research reveals new insights into hepatitis B

Researchers at the University of Delaware, working with colleagues at Indiana University, have gained new insights into the virus that causes hepatitis B—a life-threatening and incurable infection that afflicts more than ...

Health

Is margarine actually better for me than butter?

Only 20 years ago butter was the public villain – contributing to raised cholesterol levels and public concern over an increased risk of heart disease. Now this public perception seems to have been reversed, and reality ...

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Perturbation theory (quantum mechanics)

In quantum mechanics, perturbation theory is a set of approximation schemes directly related to mathematical perturbation for describing a complicated quantum system in terms of a simpler one. The idea is to start with a simple system for which a mathematical solution is known, and add an additional "perturbing" Hamiltonian representing a weak disturbance to the system. If the disturbance is not too large, the various physical quantities associated with the perturbed system (e.g. its energy levels and eigenstates) can, from considerations of continuity, be expressed as 'corrections' to those of the simple system. These corrections, being 'small' compared to the size of the quantities themselves, can be calculated using approximate methods such as asymptotic series. We can therefore study the complicated system based on our knowledge of the simpler one.

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