Oncology & Cancer

Body's natural signal carriers can help melanoma spread

A new study from Finland sheds fresh light on how melanoma cells interact with other cells via extracellular vesicles they secrete. The researchers found that extracellular vesicles secreted by melanoma cells use the so-called ...

Immunology

Antibodies gather and form a circle for defensive attack

Antibodies play a crucial role in our immune system by linking antigen recognition with complement activation for attacking foreign cells. Using high-speed atomic force microscopy, collaborative groups, including researchers ...

Diseases, Conditions, Syndromes

Skin and mucous membrane lesions as complication of pneumonia

Painful inflammatory lesions of the skin and mucous membranes may occur in children who develop bacterial pneumonia. A research group at the University Children's Hospital Zurich has recently developed a new diagnostic blood ...

Neuroscience

Study reveals mysteries of critical brain receptor complex

Glutamate receptors in the brain called AMPARs are critical for synaptic plasticity, learning and memory. Poorly functioning AMPARs have been linked to a wide range of neurological and psychiatric disorders including seizures, ...

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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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