Neuroscience

Neuronal Parkinson inclusions are different than expected

An international team of researchers involving members of the University of Basel's Biozentrum challenges the conventional understanding of the cause of Parkinson's disease. The researchers have shown that the inclusions ...

Ophthalmology

Shedding light on rhodopsin dynamics in the retina

Photoreceptor cells in our eyes can adjust to both weak and strong light levels, but we still don't know exactly how they do it. Emeritus Professor Fumio Hayashi of Kobe University and his colleagues revealed that the photoreceptor ...

Alzheimer's disease & dementia

Modified protein can prevent Alzheimer's disease in mice

The amyloid precursor protein has always been vilified as a major cause of Alzheimer's disease. One of its fragments, the amyloid-beta peptide, can break off and accumulate in the brain, giving rise to the puffy white globs ...

Medical research

Drug to treat malaria could mitigate hereditary hearing loss

The ability to hear depends on proteins to reach the outer membrane of sensory cells in the inner ear. But in certain types of hereditary hearing loss, mutations in the protein prevent it from reaching these membranes. Using ...

Oncology & Cancer

Missing molecule hobbles cell movement

Cells missing a certain protein on their surface can't move normally, UConn researchers report in Science Signaling. The research could give insight into how cells move and repair wounds in normal tissue, as well as how cancer ...

Diseases, Conditions, Syndromes

'Buzzing' in ear alerted boy to very unwelcome visitor

(HealthDay)—The Connecticut 9-year-old knew something was wrong. Three days after a routine day in the school playground, he felt something "foreign" in his right ear and persistent buzzing noises.

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Membrane

A membrane is a layer of material which serves as a selective barrier between two phases and remains impermeable to specific particles, molecules, or substances when exposed to the action of a driving force. Some components are allowed passage by the membrane into a permeate stream, whereas others are retained by it and accumulate in the retentate stream.

Membranes can be of various thickness, with homogeneous or heterogeneous structure. Membrane can also be classified according to their pore diameter. According to IUPAC, there are three different types of pore size classifications: microporous (dp < 2nm), mesoporous (2nm < dp < 50nm) and macroporous (dp > 50nm). Membranes can be neutral or charged, and particles transport can be active or passive. The latter can be facilitated by pressure, concentration, chemical or electrical gradients of the membrane process. Membranes can be generally classified into three groups: inorganic, polymeric or biological membranes. These three types of membranes differ significantly in their structure and functionality.

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