Medical research

Protein twist and squeeze confers cancer drug resistance

In 1986, cellular biochemist Kazumitsu Ueda, currently at Kyoto University's Institute for Integrated Cell-Material Sciences (iCeMS), discovered that a protein called ABCB1 could transport multiple chemotherapeutics out of ...


New tool for watching and controlling neural activity

A new molecular probe from Stanford University could help reveal how our brains think and remember. This tool, called Fast Light and Calcium-Regulated Expression or FLiCRE (pronounced "flicker"), can be sent inside any cell ...

Medical research

Diabetic drug could slow the progression of Parkinson's disease

A hallmark of Parkinson's disease is the degeneration of a group of dopaminergic neurons in the brain, which play key roles in movement initiation and co-ordination. When these neurons degenerate it leads to akinesia (lack ...

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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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