158 research outputs found
A telescopic jib for continuous adjustment
For special space applications, e.g. for experiments distant from any orbital platforms or manipulators a new kind of jibs with extreme extension capacity has to be designed. Considering the requirements, the telescopic principle is found to be the most promising. For the choice of the stiff structure, design criteria are evaluated. Special effort deals with the drive system. An electromechanical system can satisfy the requirements. First results of the development of such a drive are presented. The most significant features are: A telescopic assembly of tubes which can be mutually moved by a short spindle in the center of the package. An elastically suspended screw is located at the bottom of each tube. For the jib extension, these screws will be linked with the spindle. The control of their sequence and the adjustment of tubes in mutual end positions are performed by latches. A functional model proved the basic idea
Plant lectins: the ties that bind in root symbiosis and plant defense
Lectins are a diverse group of carbohydrate-binding proteins that are found within and associated with organisms from all kingdoms of life. Several different classes of plant lectins serve a diverse array of functions. The most prominent of these include participation in plant defense against predators and pathogens and involvement in symbiotic interactions between host plants and symbiotic microbes, including mycorrhizal fungi and nitrogen-fixing rhizobia. Extensive biological, biochemical, and molecular studies have shed light on the functions of plant lectins, and a plethora of uncharacterized lectin genes are being revealed at the genomic scale, suggesting unexplored and novel diversity in plant lectin structure and function. Integration of the results from these different types of research is beginning to yield a more detailed understanding of the function of lectins in symbiosis, defense, and plant biology in general
Characterization techniques for studying the properties of nanocarriers for systemic delivery
Nanocarriers have attracted a huge interest in the last decade as efficient drug delivery systems and diagnostic tools. They enable effective, targeted, controlled delivery of therapeutic molecules while lowering the side effects caused during the treatment. The physicochemical properties of nanoparticles determine their in vivo pharmacokinetics, biodistribution and tolerability. The most analyzed among these physicochemical properties are shape, size, surface charge and porosity and several techniques have been used to characterize these specific properties. These different techniques assess the particles under varying conditions, such as physical state, solvents etc. and as such probe, in addition to the particles themselves, artifacts due to sample preparation or environment during measurement. Here, we discuss the different methods to precisely evaluate these properties, including their advantages or disadvantages. In several cases, there are physical properties that can be evaluated by more than one technique. Different strengths and limitations of each technique complicate the choice of the most suitable method, while often a combinatorial characterization approach is needed
Distribution and properties of a âlectin- likeâ glycoprotein from leaves and stems ofDolichos biflorus: Implications on the role of lectins in plants
Determination of Surface Tension Components of Aqueous Solutions Using Fomblin HC/25 Perfluoropolyether Liquid Film as a Solid Substrate
Determination of Surface Tension Components of Aqueous Solutions Using Fomblin HC/25\uaePerfluoropolyether Liquid Film as a Solid Substrate
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