Challenges of physiological monitoring in a Navy operational setting

Challenges to physiological monitoring in the Navy include environmental extremes, acceptance of use by test subjects, data transfer, data interpretation, and capability of relating collected data to valid operational relevant criterion measures. These problems are discussed with respect to diving, electrophysiological monitoring, in-flight monitoring, aircrew fatigue, in-flight cardiac stress, and in-flight monitoring devices

Development of LANDSAT Derived Forest Cover Information for Integration into Adirondack Park GIS

Based upon observed changes in timber harvest practices partially attributable to forest biomass removable for energy supply purposes, the Adirondack Park Agency began in 1979 a multi-year project to implement a digital geographic information system (GIS). An initial developmental task was an inventory of forest cover information and analysis of forest resource change and availability. While developing the GIS, a pilot project was undertaken to evaluate the usefulness of LANDSAT derived land cover information for this purpose, and to explore the integration of LANDSAT data into the GIS. The prototype LANDSAT analysis project involved: (1) the use of both recent and historic data to derive land cover information for two dates; and (2) comparison of land cover over time to determine quantitative and geographic changes. The "recent data," 1978 full foliage data over portions of four LANDSAT scenes, was classified, using ground truth derived training samples in various forested and non-forested categories. Forested categories include the following: northern hardwoods, pine, spruce-fir, and pine plantation, while nonforested categories include wet-conifer, pasture, grassland, urban, exposed soil, agriculture, and water

Elgaria panamintina

Number of Pages: 4Integrative BiologyGeological Science

Positive contact resistance soldering unit

Ohmmeter is used to indicate positive contact between electrodes and workpiece. This permits good soldering and prevents damage to electronic devices

The measurement of sediment irrigation rates: A comparison of the BR- tracer and 222RN/226RA disequilibrium techniques

We have carried out a series of experiments designed to allow comparison of sediment irrigation rates determined simultaneously using two methods: the measurement of 222Rn/226Ra disequilibrium in pore waters, and the measurement of distributions of a tracer, Br−, which was added to the water overlying sediments at the start of incubation experiments. The experiments were carried out on fine-grained sediments from Buzzards Bay, MA. We made irrigation rate measurements on sediments in their natural state, as well as on sediments that had been treated to alter macrofaunal abundance and diversity. The range of irrigation rates measured was similar for both tracers, and was similar to rates measured at the study site previously by Martin and Sayles (1987). Furthermore, the two tracers gave similar patterns of irrigation rate variability between cores and with depth below the sediment-water interface. On the other hand, comparisons of individual cores showed significant differences in the absolute rates measured using the different tracers; in particular, the 222Rn/226Ra disequilibrium method yielded more rapid irrigation rate estimates at depths exceeding 10 cm below the sediment-water interface. These differences could be due to the inherent limitations on the sensitivity of the methods, to artifacts in measurement procedures, to differences in the permeability of burrow walls to the two tracers (Rn and Br−), or to differences in the time-scales on which the two tracers record irrigation events. Irrigation rates determined by the Br− tracer method were roughly correlated with the abundance of Nephtys incisa in the sediments, but were not related to abundances of the other numerically important deposit feeders, Nucula annulata and Mediomastus ambiseta.

Distribution of the Marsh Periwinkle Littorina irrorata (Say) in a Virginia Salt Marsh

Littorina irrorata varies over its geographic range in maximum size, preferred elevations relative to tidal datum planes, and in the type of vegetation it inhabits. On Wallops Island, Virginia, postlarvae of Littorina irrorata with shell lengths \u3c 5 mm long live almost exclusively in dead, curled-up leaves of Spartina alterniflora at elevations near mean tide level, below elevations occupied by larger conspecifics. Snails longer than 5 mm in length increase in average size with decreasing elevation. This distribution is opposite to that found by Hamilton (1978) in a marsh in Florida. No difference was found in our study area in growth rate of marked snails at two different elevations, so the size-elevation gradient probably is not caused by differences in growth rate. Snails 15 to 19 mm long are more active when exposed to reduced salinities than snails \u3e 21 mm long. The lowest salinities recorded in the marsh occurred at the highest elevations. This salinity effect, together with mortality from known size-selective predators, may account, at least in part, for the seaward increase in mean shell size

Distribution of the Marsh Periwinkle Littorina irrorata (Say) in a Virginia Salt Marsh

Littorina irrorata varies over its geographic range in maximum size, preferred elevations relative to tidal datum planes, and in the type of vegetation it inhabits. On Wallops Island, Virginia, postlarvae of Littorina irrorata with shell lengths \u3c 5 mm long live almost exclusively in dead, curled-up leaves of Spartina alterniflora at elevations near mean tide level, below elevations occupied by larger conspecifics. Snails longer than 5 mm in length increase in average size with decreasing elevation. This distribution is opposite to that found by Hamilton (1978) in a marsh in Florida. No difference was found in our study area in growth rate of marked snails at two different elevations, so the size-elevation gradient probably is not caused by differences in growth rate. Snails 15 to 19 mm long are more active when exposed to reduced salinities than snails \u3e 21 mm long. The lowest salinities recorded in the marsh occurred at the highest elevations. This salinity effect, together with mortality from known size-selective predators, may account, at least in part, for the seaward increase in mean shell size

Molecular phylogeny of brachiopods and phoronids based on nuclear-encoded small subunit ribosomal RNA gene sequences

Brachiopod and phoronid phylogeny is inferred from SSU rDNA sequences of 28 articulate and nine inarticulate brachiopods, three phoronids, two ectoprocts and various outgroups, using gene trees reconstructed by weighted parsimony, distance and maximum likelihood methods. Of these sequences, 33 from brachiopods, two from phoronids and one each from an ectoproct and a priapulan are newly determined. The brachiopod sequences belong to 31 different genera and thus survey about 10% of extant genus-level diversity. Sequences determined in different laboratories and those from closely related taxa agree well, but evidence is presented suggesting that one published phoronid sequence (GenBank accession UO12648) is a brachiopod-phoronid chimaera, and this sequence is excluded from the analyses. The chiton, Acanthopleura, is identified as the phenetically proximal outgroup; other selected outgroups were chosen to allow comparison with recent, non-molecular analyses of brachiopod phylogeny. The different outgroups and methods of phylogenetic reconstruction lead to similar results, with differences mainly in the resolution of weakly supported ancient and recent nodes, including the divergence of inarticulate brachiopod sub-phyla, the position of the rhynchonellids in relation to long- and short-looped articulate brachiopod clades and the relationships of some articulate brachiopod genera and species. Attention is drawn to the problem presented by nodes that are strongly supported by non-molecular evidence but receive only low bootstrap resampling support. Overall, the gene trees agree with morphology-based brachiopod taxonomy, but novel relationships are tentatively suggested for thecideidine and megathyrid brachiopods. Articulate brachiopods are found to be monophyletic in all reconstructions, but monophyly of inarticulate brachiopods and the possible inclusion of phoronids in the inarticulate brachiopod clade are less strongly established. Phoronids are clearly excluded from a sister-group relationship with articulate brachiopods, this proposed relationship being due to the rejected, chimaeric sequence (GenBank UO12648). Lineage relative rate tests show no heterogeneity of evolutionary rate among articulate brachiopod sequences, but indicate that inarticulate brachiopod plus phoronid sequences evolve somewhat more slowly. Both brachiopods and phoronids evolve slowly by comparison with other invertebrates. A number of palaeontologically dated times of earliest appearance are used to make upper and lower estimates of the global rate of brachiopod SSU rDNA evolution, and these estimates are used to infer the likely divergence times of other nodes in the gene tree. There is reasonable agreement between most inferred molecular and palaeontological ages. The estimated rates of SSU rDNA sequence evolution suggest that the last common ancestor of brachiopods, chitons and other protostome invertebrates (Lophotrochozoa and Ecdysozoa) lived deep in Precambrian time. Results of this first DNA-based, taxonomically representative analysis of brachiopod phylogeny are in broad agreement with current morphology-based classification and systematics and are largely consistent with the hypothesis that brachiopod shell ontogeny and morphology are a good guide to phylogeny

A challenging diagnosis of alpha-1-antitrypsin deficiency: identification of a patient with a novel F/Null phenotype

Alpha-1-antitrypsin (A1AT) deficiency is a genetic disease characterized by low levels and/or function of A1AT protein. A1AT deficiency can result in the development of COPD, liver disease, and certain skin conditions. The disease can be diagnosed by demonstrating a low level of A1AT protein and genotype screening for S and Z mutations, which are the most common. However, there are many genetic variants in A1AT deficiency, and this screening may miss rarer cases, such as those caused by dysfunctional protein. We identified a patient with a previously unreported F/null phenotype that was missed by routine screening. This case highlights the wide variation in possible mutations, limitations in diagnostics, and the importance of combining clinical suspicion with measurement of protein levels, phenotypic analysis, and in appropriate cases expanded genetic analysis