Medical research

New mechanism for dysfunctional insulin release identified

In a new study, researchers at Uppsala University have identified a previously unknown mechanism that regulates release of insulin, a hormone that lowers blood glucose levels, from the β-cells (beta cells) of the pancreas. ...

Oncology & Cancer

Novel anti-cancer nanomedicine for efficient chemotherapy

Researchers at the University of Helsinki in collaboration with researchers from Åbo Akademi University, Finland and Huazhong University of Science and Technology, China have developed a new anti-cancer nanomedicine for ...

Cardiology

Defective cilia linked to heart valve birth defects

Bicuspid aortic valve (BAV) is the most common heart valve birth defect and one of the most common birth defects of any type, affecting around 70 million people worldwide. A healthy aortic valve has three leaflets; in BAV ...

Diseases, Conditions, Syndromes

Papillomaviruses may be able to be spread by blood

Papillomavirus has traditionally been considered strictly a sexually transmitted disease, but a recent study found that rabbit and mouse papillomaviruses could be transferred by blood to their respective hosts.

Neuroscience

Mechanism of epilepsy causing membrane protein discovered

On August 21, Korea Brain Research Institute announced that a team led by principal researcher Lim Hyun-Ho discovered a new 3-D structure and membrane protein mechanism which causes epilepsy and muscle problems. The study ...

Diseases, Conditions, Syndromes

Dengue fever outbreak hits Latin America and Caribbean region

The Pan American Health Organization is warning against a deadly spike in dengue fever in Latin America and the Caribbean, and is calling on communities to eliminate mosquito breeding sites to combat the virus.

Medical research

Mosquito 'spit glands' hold key to curbing malaria, study shows

Mosquitoes can harbor thousands of malaria-causing parasites in their bodies, yet while slurping blood from a victim, they transmit just a tiny fraction of them. In an effort to define precisely the location of the parasite ...

Diabetes

New role for microtubules in diabetes

The failure of pancreatic beta cells to release appropriate amounts of insulin in response to rising blood glucose levels is a hallmark of type 2 diabetes.

Genetics

Molecular cause for severe multi-organ syndrome

Three unrelated families on three continents (from continental Portugal, the United States and Brazil), all with healthy ancestors, had children with a very rare multi-organ condition that causes early-onset retinal degeneration, ...

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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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