Frequency stabilization for mobile satellite terminals via LORAN

Digital satellite communication systems require careful management of frequency stability. Historically, frequency stability has been accomplished by continuously powered, high cost, high performance reference oscillators. Today's low cost mobile satellite communication equipment must operate under wide ranging environmental conditions, stabilize quickly after application of power, and provide adequate performance margin to overcome RF link impairments unique to the land mobile environment. Methods for frequency stabilization in land mobile applications must meet these objectives without incurring excessive performance degradation. A frequency stabilization scheme utilizing the LORAN (Long Range Navigation) system is presented

The Effects of Aerobic vs Anaerobic Exercise on Cognitive Function in College Aged Individuals

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A 3D searchable database of transgenic zebrafish gal4 and cre lines for functional neuroanatomy studies

Citation: Marquart, G. D., Tabor, K. M., Brown, M., Strykowski, J. L., Varshney, G. K., LaFave, M. C., . . . Burgess, H. A. (2015). A 3D searchable database of transgenic zebrafish gal4 and cre lines for functional neuroanatomy studies. Frontiers in Neural Circuits, 9(November), 1-17. doi:10.3389/fncir.2015.00078Transgenic methods enable the selective manipulation of neurons for functional mapping of neuronal circuits. Using confocal microscopy, we have imaged the cellular-level expression of 109 transgenic lines in live 6 day post fertilization larvae, including 80 Gal4 enhancer trap lines, 9 Cre enhancer trap lines and 20 transgenic lines that express fluorescent proteins in defined gene-specific patterns. Image stacks were acquired at single micron resolution, together with a broadly expressed neural marker, which we used to align enhancer trap reporter patterns into a common 3-dimensional reference space. To facilitate use of this resource, we have written software that enables searching for transgenic lines that label cells within a selectable 3-dimensional region of interest (ROI) or neuroanatomical area. This software also enables the intersectional expression of transgenes to be predicted, a feature which we validated by detecting cells with co-expression of Cre and Gal4. Many of the imaged enhancer trap lines show intrinsic brain-specific expression. However, to increase the utility of lines that also drive expression in non-neuronal tissue we have designed a novel UAS reporter, that suppresses expression in heart, muscle, and skin through the incorporation of microRNA binding sites in a synthetic 3? untranslated region. Finally, we mapped the site of transgene integration, thus providing molecular identification of the expression pattern for most lines. Cumulatively, this library of enhancer trap lines provides genetic access to 70% of the larval brain and is therefore a powerful and broadly accessible tool for the dissection of neural circuits in larval zebrafish. © 2015 Marquart, Tabor, Brown, Strykowski, Varshney, LaFave, Mueller, Burgess, Higashijima and Burgess

A Central Partition of Molecular Conformational Space. IV. Extracting information from the graph of cells

In previous works [physics/0204035, physics/0404052, physics/0509126] a procedure was described for dividing the $3 \times N$-dimensional conformational space of a molecular system into a number of discrete cells, this partition allowed the building of a combinatorial structure from data sampled in molecular dynamics trajectories: the graph of cells, that encodes the set of cells in conformational space that are visited by the system in its thermal wandering. Here we outline a set of procedures for extracting useful information from this structure: 1st) interesting regions in the volume occupied by the system in conformational space can be bounded by a polyhedral cone whose faces are determined empirically from a set of relations between the coordinates of the molecule, 2nd) it is also shown that this cone can be decomposed into a hierarchical set of smaller cones, 3rd) the set of cells in a cone can be encoded by a simple combinatorial sequence.Comment: added an intrduction and reference

Prepontine Non-giant Neurons Drive Flexible Escape Behavior in Zebrafish

Many species execute ballistic escape reactions to avoid imminent danger. Despite fast reaction times, responses are often highly regulated, reflecting a trade-off between costly motor actions and perceived threat level. However, how sensory cues are integrated within premotor escape circuits remains poorly understood. Here, we show that in zebrafish, less precipitous threats elicit a delayed escape, characterized by flexible trajectories, which are driven by a cluster of 38 prepontine neurons that are completely separate from the fast escape pathway. Whereas neurons that initiate rapid escapes receive direct auditory input and drive motor neurons, input and output pathways for delayed escapes are indirect, facilitating integration of cross-modal sensory information. These results show that rapid decision-making in the escape system is enabled by parallel pathways for ballistic responses and flexible delayed actions and defines a neuronal substrate for hierarchical choice in the vertebrate nervous system

Identification of a Novel 0.7-kb Polyadenylated Transcript in the LAT Promoter Region of HSV-1 That Is Strain Specific and May Contribute to Virulence

AbstractHerpes Simplex virus expresses latency-associated transcripts (LATs) the function of which remains obscure despite increasing knowledge of their structure and expression. Upstream of the LAT coding region is a region of the genome that is poorly characterized although it lies in an area that is responsible for modulation of reactivation efficiency in two different animal models. Transcript mapping with strains 17, McKrae, KOS, and F has revealed strain differences in this region of the viral genome. Strain 17 and McKrae expressed a novel polyadenylated 0.7-kb transcript that is absent from KOS and F. This transcript is expressed in the LAT direction and has the kinetics of a true late gene during the lytic cycle of infection. A deletion mutant, 17ΔBsa, which does not express the 0.7-kb RNA, is less virulent than the parental strain 17. A rescuant with F sequence (17ΔBsa/RF) shows virulence similar to F, whereas a rescuant with strain 17 sequence (17ΔBsa/R17) is similar to strain 17. Virulence is altered by deletion or substitution in the region encoding the 0.7-kb transcript (BsaI-BsaI); however, reactivation in the mouse explant cocultivation assay or the adrenergically induced rabbit reactivation model remained unchanged. The importance of this region for virulence is discussed

Modeling Subsistence Change in the Late Prehistoric Period in the Interior Lower Coastal Plain of South Carolina

Recent research on Middle-Late Woodland and Mississippian subsistence-settlement change has modified substantially the traditional models of late fall, coastal to interior transhumance patterns along the southeastern Atlantic Coast. The archeological, ethnohistorical, and environmental data suggest that the interior Lower Coastal Plain of South Carolina was exploited on a year-round basis during the late prehistoric period. These data and those recovered from two archeological sites, which were investigated by the Institute of Archeology and Anthropology for the U. S. Army Corps of Engineers\u27 Cooper River Rediversion Project, indicate differences in the subsistence strategies between the Middle-Late Woodland and Mississippian populations, however. The Middle-Late Woodland settlement pattern appears to reflect generalized exploitation of riverine and interriverine resources, whereas the Mississippian exploitation strategy apparently focuses on the intensive exploitation of a relatively narrow range of specific, high density, riverine resources. A series of interrelated hypotheses, deduced from economic ecological theory, characterizes the expected nature of these differences. The hypotheses are tested using paleoecological data and deriving archeological measures of functional variability for the artifact assemblages recovered from sites 38BK235 and 3BBK236 located in the riverine zone. The results support intensive exploitation of the interior riverine zone in the summer and early fall by both Middle-Late Woodland and Mississippian groups, with the Mississippian occupation having more and better defined activity areas and showing a greater range of diversity and functional specificity in the artifact assemblage.https://scholarcommons.sc.edu/archanth_anthro_studies/1006/thumbnail.jp