A first look at biosensors

This is a very elementary guide to biosensors, outlining the principles of operation of some optoelectronic and current measuring biosensors. Factors which can influence successful translation to the marketplace are addressed.     

A new look at the acetolysis method

The acetolysis method intreduced byGunnar Erdtman is still a very welcome and highly successful technique in palynology. However, acetolysis destroys all pollen material with the exception of sporopollenin that forms the outer pollen wall, the exine. Modern palynology in its application to plant systematics and phylogeny must consider all sporoderm characters, not only those of the exine. The neglect of the intine may distort some principal palynological aspects. This is illustrated by cases of total breakdown or gross modification of thin exine structures (e.g. inBeilschmiedia, Strelitzia) and by the clarification of apertures (e.g.,Polyalthia, Fissistigma, Calluna). In our view the investigation of both acetolysed and non-acetolysed pollen is obligatory for a well balanced view of pollen structure and function.     

A closer look at the cholesterol sensor

Transport of the sterol regulatory element-binding protein (SREBP) cleavage-activating protein (SCAP)–SREBP complex from the endoplasmic reticulum (ER) to the Golgi is the central event mediating the cholesterol-feedback process in mammalian cells. A conformational change in SCAP is a crucial step; when cholesterol levels are high, the conformation of SCAP enables the SCAP–SREBP complex to associate with an insulin-induced gene (INSIG) retention protein in the ER. By contrast, when cholesterol levels are low, SCAP switches to a conformation that enables the dissociation of the retention protein and the association of SCAP–SREBP with COP II vesicles.     

A fresh look at the open rhinoplasty technique

Use of the open rhinoplasty technique (ORT) in certain nasal and septal deformities has proven to be an invaluable asset in the rhinoplasty armamentarium of the authors. Primarily owing to the markedly increased exposure with this technique, more accurate assessment of the deformities is possible and additional or improved surgical maneuvers become available, particularly in the tip. Sculpting the entire cartilaginous and/or bony vault, as well as correcting difficult septal malalignments, can be carried out under better direct vision with greater precision, accuracy, and predictability. This has led to improved and more consistent final results. Previous criticisms of unsightly columellar scars have been virtually eliminated through the use of improved surgical techniques and simple magnification. Overall, open rhinoplasty technique can provide many distinct advantages in certain nasal deformities with no real disadvantages over conventional closed techniques.