Round-Robin evaluation of the methodology for filtration efficiency tests in different filter media against nanoparticles

The filtration of airborne nanoparticles is becoming an important issue as they are produced in large quantities from material synthesis and combustion emission. Current international standards dealing with efficiency test for filters and filter media focus on measurement of the minimum efficiency at the most penetrating particle size. The available knowledge and instruments provide a solid base for development of test methods to determine the effectiveness of filtration media against airborne nanoparticles down to single-digit nanometer range. An interlaboratory evaluation was performed under the Technical Committee 195 of European Committee for Standardization (CEN/TC195) for the development of the methodology to determine effectiveness of filtration media against airborne particles in the 3 – 500 nm range. Five different laboratories, ETH/Empa, University of Minnesota, Politecnico di Torino, Unifil and Camfil, participated in the round robin test in order to ensure the accuracy of the test method. The qualification of test rig and apparatus was performed prior of the filtration ef-ficiency measurement tests. Experimental data are presented and their validity is discussed

A similarity search algorithm to predict protein structures

Accurate prediction of protein structures is very important for many applications such as drug discovery and biotechnology. Building side chains is an essential to get any reliable prediction of the protein structure for any given a protein main chain conformation. Most of the methods that predict side chain conformations use statistically generated data from known protein structures. It is a computationally intractable problem to search suitable side chains from all possible rotamers simultaneously using information of known protein structures. Reducing the number of possibility is a main issue to predict side chain conformation. This paper proposes an enumeration based similarity search algorithm to predict side chain conformations. By introducing &ldquo;beam search&rdquo; technique, a significant number of unrelated side chain rotamers can easily be eliminated. As a result, we can search for suitable residue side chains from all possible side chain conformations.<br /