836,296 research outputs found

    Kafirin structure and functionality

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    The structural and functional properties of kafirins are reviewed. Three classes of kafirin: the a, Ăź and ? forms have been identified at the protein level and one, the d, has been identified only at the gene and transcript levels. All forms show high homology with the equivalent zein proteins. By analogy with the zeins it is believed that the a-kafirins probably have an extended hairpin structure in solution, comprising elements of a-helix, Ăź-sheet and turns folded back on itself. Kafirins are the most hydrophobic of the prolamins as shown by their solubility, and calculated hydration free energies. The proteins exhibit extensive cross-linking by disulphide bonds and on cooking form indigestible aggregates which are not solubilised by reduction of disulphide bonds. In spite of continuing studies, the reasons for the low digestibility of the protein remain uncertain and there may be several factors involved. Other research has shown that kafirins may have non-food uses and may be used to form films

    Increasing optical metamaterials functionality

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    Gold Split Ring Resonators (SRRs) were fabricated on silicon substrates by electron beam lithography and lift-off, with overall dimensions of approximately 200 nm. Reflectance spectra from the SRRs are similar to those published elsewhere. New devices are proposed based on the additional functionality afforded by the use of a silicon substrate

    Measuring neuromuscular junction functionality

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    Neuromuscular junction (NMJ) functionality plays a pivotal role when studying diseases in which the communication between motor neuron and muscle is impaired, such as aging and amyotrophic lateral sclerosis (ALS). Here we describe an experimental protocol that can be used to measure NMJ functionality by combining two types of electrical stimulation: direct muscle membrane stimulation and the stimulation through the nerve. The comparison of the muscle response to these two different stimulations can help to define, at the functional level, potential alterations in the NMJ that lead to functional decline in muscle. Ex vivo preparations are suited to well-controlled studies. Here we describe an intensive protocol to measure several parameters of muscle and NMJ functionality for the soleus-sciatic nerve preparation and for the diaphragm-phrenic nerve preparation. The protocol lasts approximately 60 min and is conducted uninterruptedly by means of a custom-made software that measures the twitch kinetics properties, the force-frequency relationship for both muscle and nerve stimulations, and two parameters specific to NMJ functionality, i.e. neurotransmission failure and intratetanic fatigue. This methodology was used to detect damages in soleus and diaphragm muscle-nerve preparations by using SOD1G93A transgenic mouse, an experimental model of ALS that ubiquitously overexpresses the mutant antioxidant enzyme superoxide dismutase 1 (SOD1)

    Multiple Functionality in Nanotube Transistors

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    Calculations of quantum transport in a carbon nanotube transistor show that such a device offers unique functionality. It can operate as a ballistic field-effect transistor, with excellent characteristics even when scaled to 10 nm dimensions. At larger gate voltages, channel inversion leads to resonant tunneling through an electrostatically defined nanoscale quantum dot. Thus the transistor becomes a gated resonant tunelling device, with negative differential resistance at a tunable threshold. For the dimensions considered here, the device operates in the Coulomb blockade regime, even at room temperature.Comment: To appear in Phys. Rev. Let

    Evolution in the Design and Functionality of Rubrics: from “Square” Rubrics to “Federated” Rubrics

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    The assessment of learning remains one of the most controversial and challenging aspects for teachers. Among some recent technical solutions, methods and techniques like eRubrics emerge in an attempt to solve the situation. Understanding that all teaching contexts are different and there can be no single solution for all cases, specific measures are adapted to contexts where teachers receive support from institutions and communities of practice. This paper presents the evolution of the eRubric service [1] which started from a first experience with paper rubrics, and, with time and after several I+D+R [2] educational projects, has evolved thanks to the support of a community of practice [3] and the exchange of experiences between teachers and researchers. This paper shows the results and functionality of the eRubrics service up to the date of publicationa.) Project I+D+i EDU2010-15432: eRubric federated service for assessing university learning http://erubrica.uma.es/?page_id=434. b.) Centre for the Design of eRubrics. National Distance Education System -Sined- Mexico. [http://erubrica.uma.es/?page_id=389

    TLC determination of functionality in prepolymers

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    Application of thin-layer chromatographics provides rapid qualitative determination of functional distribution in experimental prepolymer. Functionality distribution is of fundamental importance for it determines; (1) manner in which given carboxyl-terminated prepolymer will cure and (2) physical properties of resulting product

    Materials chemistry: Design, Synthesis and Functionality

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    The need to synthesise new materials is driven by the need for materials with specific functionality, which is in turn driven by the intended final application. In this talk we will explore the design of materials based on the application for which they are intended and the ways in which they can be synthesised and characterised. From the materials perspective we will focus on inorganic–organic hybrid materials, metal phosphonates and metal oxides, and discuss how we can make such materials which exhibit properties of luminescence and antimicrobial activity. Characterisation of materials using crystallography, photoluminescence and adsorption spectroscopies, and how the biological activity of materials is determined will be discussed.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
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