2,330 research outputs found
Aucklandea and Leschenea, Two New Monotypic Genera from New Zealand (Coleoptera: Staphylinidae: Pselaphinae), and a Key to New Zealand Genera of the Supertribe Faronitae
© 2015, Entomological Society of America. All rights reserved. Two new genera and two new species of New Zealand endemic pselaphine staphylinid beetles are described as follows: Aucklandea Park and Carlton, gen. nov., based on Aucklandea fusca Park and Carlton, sp. nov.; and Leschenea Park and Carlton, gen. nov., based on Leschenea richardi Park and Carlton, sp. nov. Illustrations of habitus and major diagnostic characters, distribution maps, and an identification key of all New Zealand genera of the pselaphine supertribe Faronitae are provided
Phyllosilicate Deposits in Shalbatana Vallis
Shalbatana Vallis is an ancient river valley on Mars, the westernmost of the southern Chryse outflow channels. The geologic history of this area has significant implications for understanding Mars' hydrologic and climate history. The highland flood basalts are cut by large collapse depressions, multiple outflow channels, and chaotic terrain. An intravalley paleolake with a depth of over 400 m, in the 125 km diameter Orson Welles crater (Fig. 1) and the adjacent section of Shalbatana Vallis, was deduced from Mars Orbiter Laser Altimeter (MOLA) topography, evidence of shorelines and the occurrence of fan-delta deposits, including Gilbert-style deltas [1]. A number of CRISM (Compact Reconnaissance Imaging Spectrometer for Mars) images with strong phyllosilicate signatures have been identified throughout the channel and nearby highlands (Fig. 1). A majority of the signatures are concentrated in areas exposed by impact cratering. Since such minerals can form by a variety of different geological processes, such as weathering, burial diagenesis, and hydrothermal alteration [2], the nature of the phyllosilicate deposits in the Shalbatana Vallis region may provide insights into the formation processes that took place and help to place constraints on the early aqueous activity in the region
Effect of channel size on sweet potato storage root enlargement in the Tuskegee University hydroponic nutrient film system
The potential of the sweet potato as a food source for future long term manned space missions is being evaluated for NASA's Controlled Ecological Life Support Systems (CELSS) program. Sweet potatoes have been successfully grown in a specially designed Tuskegee University nutrient film technique (TU NFT) system. This hydroponic system yielded storage roots as high as 1790 g/plant fresh weight. In order to determine the effect of channel size on the yield of sweet potatoes, the width and depth of the growing channels were varied in two separate experiments. Widths were studied using the rectangular TU NFT channels with widths of 15 cm (6 in), 30 cm (12 in) and 45 cm (18 in). Channel depths of 5 cm (2 in), 10 cm (4 in), and 15 cm (6 in) were studied using a standard NASA fan shaped Biomass Production Chamber (BPC) channel. A comparison of preliminary results indicated that, except for storage root number, the growth and yield of sweet potatoes were not affected by channel width. Storage root yield was affected by channel depth although storage root number and foliage growth were not. Both experiments are being repeated
Marine Bioinvasions and Climate Change
BACKGROUND
Invasive species are second only to habitat destruction as the greatest cause of species endangerment and global biodiversity loss. Invasive species can cause severe and permanent damage to the ecosystems they invade. Consequences of invasion include competition with or predation upon native species, hybridization, carrying or supporting harmful pathogens and parasites that may affect wildlife and human health, disturbing ecosystem function through alteration of food webs and nutrient recycling rates, acting as ecosystem engineers and altering habitat structure, and degradation of the aesthetic quality of our natural resources. In many cases we may not fully know the native animals and plants in an area. For example, Aureophycus aleuticus, a large kelp was just described with similar discoveries of new taxa in many other latitudes. Invasive species have the potential to permanently change ecosystems before we fully understand the native communities. Recent studies suggest that invasive species share similar traits that allow for easier establishment in habitats that become disrupted by climate change. The examples below highlight some of the ongoing and expected changes to marine ecosystems that may occur as a result of the interactions between global climate change and biological invasion
Effect of biweekly shoot tip harvests on the growth and yield of Georgia Jet sweet potato grown hydroponically
Sweet potato shoot tips have been shown to be a nutritious green vegetable. A study was conducted to determine the effect of biweekly shoot tip harvests on the growth and yield of Georgia Jet sweet potato grown in the greenhouse using the nutrient film technique (NFT). The nutrient solution consisted of a modified half Hoagland solution. Biweekly shoot tip harvests, beginning 42 days after planting, provided substantial amounts of vegetable greens and did not affect the fresh and dry foliage weights or the storage root number and fresh and dry storage root weights at final harvest. The rates of anion and cation uptake were not affected by tip harvests
Life Beneath Glacial Ice - Earth(!) Mars(?) Europa(?)
We are investigating a set of cold springs that deposit sulfur and carbonate minerals on the surface of a Canadian arctic glacier. The spring waters and mineral deposits contain microorganisms, as well as clear evidence that biological processes mediate subglacial chemistry, mineralogy, and isotope fractionation . The formation of native sulphur and associated deposits are related to bacterially mediated reduction and oxidation of sulphur below the glacier. A non-volcanic, topography driven geothermal system, harboring a microbiological community, operates in an extremely cold environment and discharges through solid ice. Microbial life can thus exist in isolated geothermal refuges despite long-term subfreezing surface conditions. Earth history includes several periods of essentially total glaciation. lee in the near subsurface of Mars may have discharged liquid water in the recent past Cracks in the ice crust of Europa have apparently allowed the release of water to the surface. Chemolithotrophic bacteria, such as those in the Canadian springs, could have survived beneath the ice of "Snowball Earth", and life forms with similar characteristics might exist beneath the ice of Mars or Europa. Discharges of water from such refuges may have brought to the surface living microbes, as well as longlasting chemical, mineralogical, and isotopic indications of subsurface life
Quantum-limited metrology and Bose-Einstein condensates
We discuss a quantum-metrology protocol designed to estimate a physical
parameter in a Bose-Einstein condensate of N atoms, and we show that the
measurement uncertainty can decrease faster than 1/N. The 1/N scaling is
usually thought to be the best possible in any measurement scheme. From the
perspective of quantum information theory, we outline the main idea that leads
to a measurement uncertainty that scales better than 1/N. We examine in detail
some potential problems and challenges that arise in implementing such a
measurement protocol using a Bose-Einstein condensate. We discuss how some of
these issues can be dealt with by using lower-dimensional condensates trapped
in nonharmonic potentials.Comment: 32 pages, 1 figure, updated reference
Sample Curation at a Lunar Outpost
The six Apollo surface missions returned 2,196 individual rock and soil samples, with a total mass of 381.6 kg. Samples were collected based on visual examination by the astronauts and consultation with geologists in the science back room in Houston. The samples were photographed during collection, packaged in uniquely-identified containers, and transported to the Lunar Module. All samples collected on the Moon were returned to Earth. NASA's upcoming return to the Moon will be different. Astronauts will have extended stays at an out-post and will collect more samples than they will return. They will need curation and analysis facilities on the Moon in order to carefully select samples for return to Earth
Reversible quantum operations and their application to teleportation
Quantum operations provide a general description of the state changes allowed
by quantum mechanics. Simple necessary and sufficient conditions for an ideal
quantum operation to be reversible by a unitary operation are derived in this
paper. These results generalize recent work on reversible measurements by
Mabuchi and Zoller [Phys. Rev. Lett. {\bf 76}, 3108 (1996)]. Quantum
teleportation can be understood as a special case of the problem of reversing
quantum operations. We characterize completely teleportation schemes of the
type proposed by Bennett {\it et al.} [Phys. Rev. Lett. {\bf 70}, 1895 (1993)].Comment: 10 pages, Revte
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