In Drosophila melanogaster olfactory sensory neurons (OSNs) establish synapses with projection neurons (PNs) and local interneurons within antennal lobe (AL) glomeruli. Substantial knowledge regarding this circuitry has been obtained by functional studies, whereas ultrastructural evidence of synaptic contacts is scarce. To fill this gap, we studied serial sections of three glomeruli using electron microscopy. Ectopic expression of a membrane-bound peroxidase allowed us to map synaptic sites along PN dendrites. Our data prove for the first time that each of the three major types of AL neurons is both pre-and postsynaptic to the other two types, as previously indicated by functional studies. PN dendrites carry a large proportion of output synapses, with approximately one output per every three input synapses. Detailed reconstructions of PN dendrites showed that these synapses are distributed unevenly, with input and output sites partially segregated along a proximal-distal gradient and the thinnest branches carrying solely input synapses. Moreover, our data indicate synapse clustering, as we found evidence of dendritic tiling of PN dendrites. PN output synapses exhibited T-shaped presynaptic densities, mostly arranged as tetrads. In contrast, output synapses from putative OSNs showed elongated presynaptic densities in which the T-bar platform was supported by several pedestals and contacted as many as 20 postsynaptic profiles. We also discovered synaptic contacts between the putative OSNs. The average synaptic density in the glomerular neuropil was about two synapses/mm 3 . These results are discussed with regard to current models of olfactory glomerular microcircuits across species. J. Comp. Neurol. 524:1920-1956, 2016. INDEXING TERMS: Drosophila melanogaster; olfactory system; glomerulus; projection neuron; ultrastructure; synaptic microcircuitsThe neural circuitry of the antennal lobe (AL) of the vinegar fly Drosophila melanogaster is one of the principal models for the study of how chemosensory information is processed in the brain. Thus it has been investigated intensively with a variety of anatomical, physiological, and genetic methods (Stocker, 1994;Vosshall and Stocker, 2007;Wilson, 2011). Very little is known, however, about the synaptic circuitry, synapse structure, numbers, and identity of pre-and postsynaptic components of this brain center.The olfactory sensory neurons (OSNs) located in the antennae and maxillary palps send axons to the AL, where they form synapses with different types of interneurons within functional and morphological units called glomeruli (Stocker, 1994;Couto et al., 2005). These generic structural features of glomerular anatomy are preserved across species (Hildebrand and Shepherd, 1997;Ache and Young, 2005;Martin et al., 2011). Olfactory glomeruli are spherical structures of synaptic neuropilThis is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work...

This paper describes methods for estimating building losses that were developed for the FEMA/NIBS earthquake loss estimation methodology (Whitman et al., 1997). These methods are of a new form and represent a significant step forward in the prediction of earthquake impacts. Unlike previous building loss models that are based on Modified Mercalli Intensity, the new methods use quantitative measures of ground shaking (and ground failure) and analyze model building types in a similar manner to the engineering analysis of a single structure. Direct economic losses predicted by these new methods for typical single-family homes compare well with observed losses to Los Angeles County residences damaged by the 1994 Northridge Earthquake.

This study investigates the relationship between the intelligibility and quality of modified speech in noise and in quiet. Speech signals were processed by seven algorithms designed to increase speech intelligibility in noise without altering speech intensity. In three noise maskers, including both stationary and fluctuating noise at two signal-to-noise ratios (SNR), listeners identified keywords from unmodified or modified sentences. The intelligibility performance of each type of speech was measured as the listeners' word recognition rate in each condition, while the quality was rated as a mean opinion score. In quiet, only the perceptual quality of each type of speech was assessed. The results suggest that when listening in noise, modification performance on improving intelligibility is more important than its potential negative impact on speech quality. However, when listening in quiet or at SNRs in which intelligibility is no longer an issue to listeners, the impact to speech quality due to modification becomes a concern.

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In the Imperial County, California, earthquake of 15th October 1979, the Imperial County Services Building was seriously damaged — and has subsequently been demolished. At the time of the earthquake there were approximately 123 occupants in the six‐storey reinforced concrete building which housed a number of county service departments. This paper investigates occupant behavior in a building subjected to an earthquake, and describes, in detail, what people do during and immediately subsequent to the shock.