COBE's search for structure in the Big Bang

The launch of Cosmic Background Explorer (COBE) and the definition of Earth Observing System (EOS) are two of the major events at NASA-Goddard. The three experiments contained in COBE (Differential Microwave Radiometer (DMR), Far Infrared Absolute Spectrophotometer (FIRAS), and Diffuse Infrared Background Experiment (DIRBE)) are very important in measuring the big bang. DMR measures the isotropy of the cosmic background (direction of the radiation). FIRAS looks at the spectrum over the whole sky, searching for deviations, and DIRBE operates in the infrared part of the spectrum gathering evidence of the earliest galaxy formation. By special techniques, the radiation coming from the solar system will be distinguished from that of extragalactic origin. Unique graphics will be used to represent the temperature of the emitting material. A cosmic event will be modeled of such importance that it will affect cosmological theory for generations to come. EOS will monitor changes in the Earth's geophysics during a whole solar color cycle

Quantitative Imaging Ion Microscopy: A Short Review

A short review of recent efforts being made in the quantification of images in ion microscopy is given. Special aspects of instrumentation, detection and acquisition, which are unique to direct imaging secondary ion mass spectrometry, are discussed in relation to the successful application of traditional empirical quantification schemes. Application of such quantification schemes requires proper sample preparation, standardization, analysis, and quite often, special techniques in image processing and the correlation of ion microscopy with other microscopies. Quantification within this technique is a difficult goal which can only be realized if the analyst pays strict attention to every step of the analytical process

Aerospace medicine and biology: A cumulative index to a continuing bibliography (supplement 306)

This publication is a cumulative index to the abstracts contained in the Supplements 294 through 305 of Aerospace Medicine and Biology: A Continuing Bibliography. It includes seven indexes - subject, personal author, corporate source, foreign technology, contract number, report number, and accession number

Contemporary mesozooplankton communities of the Beaufort Sea

Thesis (M.S.) University of Alaska Fairbanks, 2015Zooplankton are critical trophic links and important modifiers of organic carbon cycles, yet are poorly characterized for much of the Arctic's Beaufort Sea, particularly in mesopelagic (> 200 m) waters. Zooplankton were sampled with 150 and 505 μm mesh nets in the upper 200 m in sections of the Beaufort Sea between Barrow Canyon and the Mackenzie River during August and September 2010-2013 to characterize the species composition, abundance, and biomass of epipelagic Beaufort Sea zooplankton communities. I observed 106 taxonomic zooplankton categories during four field seasons across both mesh sizes; copepods exhibited the highest species richness (38 species), followed by cnidarians (16 species) and amphipods (14 species). Average holozooplankton abundance ranged from 1110-3880 ind. m⁻³ in the 150-μm net and 47-215 ind. m⁻³ in the 505-μm net. Average holozooplankton biomass ranged from 23.8-76.9 mg dry-weight (DW) m⁻³ and 13.9-57.6 mg DW m⁻³ in the 150-μm and 505-μm nets, respectively. Spatial structure of zooplankton communities reflected a blending of across- and along-shelf temperature and salinity gradients that were driven by relative contributions of different water mass types. To characterize mesopelagic zooplankton communities of the Beaufort Sea, I collected stratified zooplankton samples and physical oceanographic data at stations along the Beaufort Sea slope during August 2013. I documented 93 taxonomic categories; greatest diversity was observed in the copepods (48 species), followed by the cnidarians (10 species) and amphipods (8 species). Distinct zooplankton communities were associated with the three main water masses in the study region: the Polar Mixed Layer (PML), Arctic Halocline Water (AHW), and Atlantic Water (AW). Average abundance and biomass were highest (1150 ind. m⁻³ and 27.1 mg DW m⁻³ , respectively) in the PML (0-50 m) and declined with depth, to a minimum in the 500-1000 m layer of AW (15 ind. m⁻³ and 0.6 mg DW m⁻³). Conversely, species richness increased with depth. Community structure was highly correlated with salinity and depth, both in terms of abundance (Spearman correlation (ρ) = 0.84, p < 0.01) and biomass (ρ = 0.81, p < 0.01). Zooplankton communities in the Beaufort Sea exhibit structure along three axes: alongshore, across-shore, and depth-related. Community structure along these axes reflects hydrographic gradients created by different water masses and physical factors in the study region. This work provides a contemporary benchmark for Beaufort Sea zooplankton community species composition, abundance, and biomass from which future change may be assessed