A Cation-π Interaction in the Binding Site of the Glycine Receptor Is Mediated by a Phenylalanine Residue

Cys-loop receptor binding sites characteristically contain many aromatic amino acids. In nicotinic ACh and 5-HT3 receptors, a Trp residue forms a cation-{pi} interaction with the agonist, whereas in GABAA receptors, a Tyr performs this role. The glycine receptor binding site, however, contains predominantly Phe residues. Homology models suggest that two of these Phe side chains, Phe159 and Phe207, and possibly a third, Phe63, are positioned such that they could contribute to a cation-{pi} interaction with the primary amine of glycine. Here, we test this hypothesis by incorporation of a series of fluorinated Phe derivatives using unnatural amino acid mutagenesis. The data reveal a clear correlation between the glycine EC50 value and the cation-{pi} binding ability of the fluorinated Phe derivatives at position 159, but not at positions 207 or 63, indicating a single cation-{pi} interaction between glycine and Phe159. The data thus provide an anchor point for locating glycine in its binding site, and demonstrate for the first time a cation-{pi} interaction between Phe and a neurotransmitter

Statistical aspects in the Styrian Salmonella surveillance program in pigs

Surveillance and Monitoring programs to substantiate freedom of disease are becoming increasingly important. Sample sizes and the right selection of the samples play a decisive role. In the course of this paper the sampling schemes for the Styrian Salmonella surveillance program in pigs are presented. The influence of diagnostic tests on the result of the estimation of prevalence is discussed and different sample sizes depending on the sensitivity and the specificity of the used diagnostic test are calculated

Technical Support Document: Development of the Advanced Energy Design Guide for K-12 Schools--30% Energy Savings

This Technical Support Document describes the process and methodology for the development of the Advanced Energy Design Guide for K-12 School Buildings (K-12 AEDG), a design guidance document intended to provide recommendations for achieving 30% energy savings in K-12 Schools over levels contained in ANSI/ASHRAE/IESNA Standard 90.1-1999, Energy Standard for Buildings Except Low-Rise Residential Buildings. The 30% energy savings target is the first step toward achieving net-zero energy schools; schools that, on an annual basis, draw from outside sources less or equal energy than they generate on site from renewable energy sources

Diagonally Neighbour Transitive Codes and Frequency Permutation Arrays

Constant composition codes have been proposed as suitable coding schemes to solve the narrow band and impulse noise problems associated with powerline communication. In particular, a certain class of constant composition codes called frequency permutation arrays have been suggested as ideal, in some sense, for these purposes. In this paper we characterise a family of neighbour transitive codes in Hamming graphs in which frequency permutation arrays play a central rode. We also classify all the permutation codes generated by groups in this family

Results of the Styrian Salmonella surveillance in pigs

A comprehensive study has been performed to obtain an overview of the Salmonella situation in Styrian slaughter pig herds. Based on a representative sampling plan 833 slaughter pigs were tested for Salmonella in four test series (winter 1997 to summer 1998). The samples, faeces as well as mesenteric and liver lymph nodes, were taken directly at the slaughter line and examined in the laboratory within 24 hours. The examination of the slaughter pigs so far yielded a Salmonella detection rate of 2.9% and a confidence interval (S =95%) from 1.9% to 4.2%. Salmonella was most frequently isolated from the mesenteric and liver lymph nodes (20 isolates; 2.4% ), but was found in the intestinal contents in only 7 cases (0.8% ). In three slaughter pigs both lymph nodes and intestinal contents were Salmonella-positive. The total of 27 Salmonella isolates comprised six different serovars. The most frequent serovars were S. enteritidis, S. typhimurium and S. hadar. 4 serovars of S. typhimurium DT 104 and 5 serovars of S. hadar were identified as multiresistent. The examination of the cut surfaces of 1,040 split carcasses by means of a wipe swab sample yielded a Salmonella detection rate of 0.4%. In the serological examination of 2,3 10 blood samples of slaughter pigs from 330 pig farms, using the SALMOTYPE0 Meat Juice ELISA, 14 animals (0.6%)from IOfarms (3%) were found to be positive, and 41 animals (1.8%) from 27 farms (8.2%) were suspected to be positive. 2,255 samples (97.6%) from 293 herds (88.8%) were found to be negative

Development of Design Guidance for K-12 Schools from 30% to 50% Energy Savings: Preprint

This paper describes the development of energy efficiency recommendations for achieving 30% whole-building energy savings in K-12 schools over levels achieved by following the ANSI/ASHRAE/IESNA Standard 90.1. These design recommendations look at building envelope, fenestration, lighting systems (including electrical lights and daylighting), HVAC systems, building automation and controls, outside air treatment, and service water heating