Osmoregulation of chloride channels in epithelial cells

__Abstract__ The plasma membrane of mammalian cells is formed by two layers of lipids (lipid bilayer), primarily phospholipids, glycolipids and cholesterol, in which many different proteins are embedded. Phospholipid consists of a glycerol backbone esterified to fatty acids (the "lipid tail") and, via a phosphate group, to either choline, serine, inositol or ethanolamine (the "head group"). Whereas the head group is hydrophilic and oriented towards the outer surface of the membrane, the lipid tail is hydrophobic and pointed towards the inner part. The plasma membrane is impermeable to large molecules like carbohydrates and proteins but readily permeable to small uncharged molecules like oxygen, water, and carbon dioxide. Molecules can move through the membrane either by direct diffusion or through specialized channels or transport proteins (facilitated diffusion). In an isolated system, as stated by the Second Law of Thermodynamics, all events move spontaneously from a higher energy state to a lower energy state and are driven by the tendency to increase the entropy (degree for randomness/ disorder). When molecules are evenly distributed throughout the available space, the entropy is at its maximum. Therefore, free moving molecules and atoms (i.e. not part of a crystal structure and not restrained by additional forces) tend to distribute themselves over an as large as possible area. As a consequence of the Second Law of Thermodynamics, differences in the concentrations of non-permeable solutes between the cell and its surrounding medium will result in a redistribution of the solvent (e.g. water) to maintain the lowest energy possible, a phenomenon known as osmosis. Therefore, in response to an osmotic imbalance, water will move across a semi-permeable membrane until the water molecules are equally distributed, resulting in swelling or shrinkage. The Gibbs-Don nan effect refers to the observation that under certain conditions charged molecules or ions fail to distribute evenly across a semi-permeable membrane. At the Gibbs-Donnan equilibrium, the total number of positive charges balanced the total number of negative charges (bulk electroneutrality). Due to the presence of charged membrane-impermeable macromolecules and the electrogenic Na+ /K+ pump, however, the Gibbs Donnan equilibrium will never be obtained in an intact cell, leading to an asymmetric distribution of permeable ions and the generation of the membrane potential. A consequence of the presence of negatively charged membrane-impermeable proteins is the constant tendency of cells to accumulate water. To counteract a potential increase in volume, sodium is removed from the cells by the Na+ /K+ pump on the expenditure of metabolic energy. Because alterations in cell volume may affect many biochemical and physiological processes, almost all cell types have additional mechanisms to regulate their volume and to limit or prevent swelling and shrinkage

Human Cytomegalovirus Cytoplasmic Virion Assembly Complex: Structure In Vivo And Role Of Pul103 In Its Biogenesis

Human Cytomegalovirus (HCMV) is a linear, double stranded DNA virus that causes severe disease in the immunocompromised, and is one of the common cause of congenital disease. Antivirals that are currently available for treatment target the DNA replication of the virus cycle, and are highly toxic. Finding new drug targets, such as proteins responsible for virion assembly and egress, would help to alleviate the disease burden. HCMV remodels the host cell to form a structure called the cytoplasmic virion assembly complex (cVAC), a site of virion maturation and egress. The first objective of this work is to study the structure of the cVAC in vivo by immunofluorescence assay using slides from children with congenital HCMV, and we discovered that the cVAC is also formed in vivo. The second objective is to elucidate the role of pUL103 in cVAC biogenesis in the early stages of infection using a regulatable pUL103-FKBP construct and Shield-1 ligand. We found that decreased levels of pUL103 at the early stages of infection is not critical for cVAC biogenesis at later times of the infection

Electro-optical method of distinguishing recyclable plastics

The UK produces 3 million tonnes of plastic waste each year, of which 85% is landfilled, 8% is incinerated and only 7% recycled. Recycling just one plastic bottle saves enough energy to power a 60W light bulb for six hours. Our local East Riding of Yorkshire Council is trying to reduce the amount of waste by recycling different types of waste. However, not all plastics can be recycled by the council currently. The aim of this project is to develop a device that can distinguish between the different types of plastic which can be and cannot be recycled with the help of an infrared spectrometer. Different types of plastics (e.g., PVC, PET, HDPE) have different forms of spectra. Materials can be identified by comparing their spectra to reference spectra. The aim here is to make a cheap and simple device to do this in the home. This could be in a form of a box containing an infrared source that will illuminate the plastic to be tested, perhaps through a set of filters of plastics that can be recycled. If the light passes through both filter and plastic under test onto a detector this will collect the radiation and pass a signal to an electronic circuit to indicate its suitability for recycling

Electro-optical method of distinguishing recyclable plastics

The UK produces 3 million tonnes of plastic waste each year, of which 85% is landfilled, 8% is incinerated and only 7% recycled. Recycling just one plastic bottle saves enough energy to power a 60W light bulb for six hours. Our local East Riding of Yorkshire Council is trying to reduce the amount of waste by recycling different types of waste. However, not all plastics can be recycled by the council currently. The aim of this project is to develop a device that can distinguish between the different types of plastic which can be and cannot be recycled with the help of an infrared spectrometer. Different types of plastics (e.g., PVC, PET, HDPE) have different forms of spectra. Materials can be identified by comparing their spectra to reference spectra. The aim here is to make a cheap and simple device to do this in the home. This could be in a form of a box containing an infrared source that will illuminate the plastic to be tested, perhaps through a set of filters of plastics that can be recycled. If the light passes through both filter and plastic under test onto a detector this will collect the radiation and pass a signal to an electronic circuit to indicate its suitability for recycling

Space Biosciences Division

In the Space Biosciences Division at NASA's Ames Research Center, we perform the biological research and technology development necessary to tackle the challenges of living in the extreme environments of space and to enable NASA's long-term human exploration mission. This brochure provides a broad overview for our research and development capabilities, several case study examples, and finally real-world applications and collaborative partnerships

REPRESENTASI FILM SEBAGAI DIPLOMASI BUDAYA (ANALISIS SEMIOTIKA BARTHES FILM ME VS MAMI SEBAGAI DIPLOMASI BUDAYA PADANG)

Entertainment industry is growing along with the development of communication technology especially in the film industry. Various films are created with a specific discourse or agenda. Not apart from the effort to introduce a culture, propaganda, tourism and so forth. One of the interesting things is cultural diplomacy that is done through a movie. Like one example of Me vs. Mami film that seeks to introduce Padang culture. With semiotics analysis Roland Barthes, the researchers are interested to see the representation posed in film scenes to introduce Padang culture as a form of cultural diplomacy.Keywords : Film, Cultural Diplomacy, Roland Barthes Semiotic

Microwave Photonics: Current challenges towards widespread application

Microwave Photonics, a symbiotic field of research that brings together the worlds of optics and radio frequency is currently facing several challenges in its transition from a niche to a truly widespread technology essential to support the ever-increasing values for speed, bandwidth, processing capability and dynamic range that will be required in next generation hybrid access networks. We outline these challenges, which are the subject of the contributions to this focus issue

Experimental demonstration of high-speed full-duplex reconfigurable free-space card-to-card optical interconnects

A high-speed full-duplex free space based card-to-card optical interconnect architecture with flexibility and reconfigurablity is proposed and experimentally demonstrated. 3×3 10Gb/s data transmission for up to 30cm is achieved with receiver sensitivity better than -11.5dBm

Performance of reconfigurable free-space card-to-card optical interconnects under atmospheric turbulence

Free-space based card-to-card optical interconnects are promising candidates for the provision of parallel high-speed and reconfigurable interconnectivity in data-centers and high-performance computing clusters. However, the atmospheric turbulence may degrade the interconnect performance due to the beam wander, signal scintillation, and beam broadening effects. In this paper, the experimental investigation of the impact of both moderate and comparatively strong atmospheric turbulence on the bit-error-rate (BER) performance of our proposed reconfigurable free-space card-to-card optical interconnects is presented. Experimental results show that the BER performance does suffer power penalties of ∼0.5 dB and ∼1.6 dB at BER of 10 -9 under moderate and strong levels of turbulence respectively

Free-space optics for high speed reconfigurable card-to-card optical interconnects

High-speed card-to-card optical interconnects are highly demanded in high-performance computing and data centers. Compared with other solutions, free-space optical interconnects have the capability of providing both reconfigurability and flexibility. In this paper we propose and experimentally demonstrate a free-space based reconfigurable optical interconnect architecture and it is capable of connecting cards located both inside the same rack as well as in different racks. Results show that 3xiO Gb/s data transmission is achieved with a worst-case receiver sensitivity better than -9.38 dBm