15,332 research outputs found
Two generic transfers and a synonymy for some North American Elateridae (Coleoptera)
During various studies, three instances of necessary taxonomic change were found. These changes are provided here to clarify the taxonomy of these taxa for those studies
Set Systems Containing Many Maximal Chains
The purpose of this short problem paper is to raise an extremal question on
set systems which seems to be natural and appealing. Our question is: which set
systems of a given size maximise the number of -element chains in the
power set ? We will show that for each fixed
there is a family of sets containing
such chains, and that this is asymptotically best possible. For smaller set
systems we are unable to answer the question. We conjecture that a `tower of
cubes' construction is extremal. We finish by mentioning briefly a connection
to an extremal problem on posets and a variant of our question for the grid
graph.Comment: 5 page
The first report of \u3ci\u3eLissomus\u3c/i\u3e Dalman (Coleoptera: Elateridae: Lissominae) from the Greater Antilles, with two new species from the Dominican Republic
Lissomus quisqueya new species and L. woodruffi new species are described. Both species are reported from the Dominican Republic on the island of Hispaniola. These are the first species of Lissomus Dalman reported from the Greater Antilles. Lissomus quisqueya is recorded from montane mesic forests in the Cordillera Central from Dajadon and La Vega provinces. Lissomus woodruffi is recorded from Barahona, Independencia and Pedernales provinces from montane mesic forest in the Sierra de Bahoruco. Morphologically, these species are most similar to members of the L. discedens Bonvouloir species group from Mesoamerica and South America. Known sites of occurrence of L. quisqueya and L. woodruffi are remnants of formerly more extensive mesic forests. Some of the specimens were found in secondary forests and ecotonal areas at sites near to primary forest or remnants, and all these forests are threatened by anthropogenic activities and stochastic climate changes.
Se describen por primera vez especies nuevas de Lissomus quisqueya y su especie hermana L. woodruffi. Ambas especies son de República Dominicana en la isla Hispaniola. Éstas son las primeras especies de Lissomus Dalman reportadas en las Antillas Mayores. Lissomus quisqueya se registra en bosques mésicos premontanos en la Cordillera Central de las provincias de Dajadon y La Vega. Lissomus woodruffi se registra en las provincias de Barahona, Independencia y Pedernales del bosque montano mésico de la Sierra de Bahoruco. Morfológicamente, este par de especies es muy similar a los miembros del grupo L. discedens Bonvouloir de Mesoamérica y Sudamérica. Los sitios conocidos de ocurrencia de L. quisqueya y L. woodruffi son ahora remanentes de bosques mésicos anteriormente más extensos. Aunque algunos de los escarabajos se encontraron en bosques secundarios y áreas ecotonales, dichos sitios estaban cerca de bosques primarios o remanentes, y todos están amenazados por actividades antropogénicas y cambios climáticos estocásticos
\u3ci\u3eTrixagus steineri\u3c/i\u3e (Coleoptera: Throscidae), a new species and fi rst genus record from The Bahamas
Trixagus steineri Johnson new species (Coleoptera: Throscidae) is described from New Providence Island, The Bahamas. This is the fi rst report of Trixagus Kugelann from The Bahamas and the first of Throscidae since the transfer of Lissominae to Elateridae
New research on bioregenerative air/water purification systems
For the past several years, air and water purification systems have been developed and used. This technology is based on the combined activities of plants and microorganisms as they function in a natural environment. More recently, researchers have begun to address the problems associated with indoor air pollution. Various common houseplants are currently being evaluated for their abilities to reduce concentrations of volatile organic compounds (VOCS) such as formaldehyde and benzene. With development of the Space Exploration Initiative, missions will increase in duration, and problems with resupply necessitates implementation of regenerative technology. Aspects of bioregenerative technology have been included in a habitat known as the BioHome. The ultimate goal is to use this technology in conjunction with physicochemical systems for air and water purification within closed systems. This study continued the risk assessment of bioregenerative technology with emphasis on biological hazards. In an effort to evaluate the risk for human infection, analyses were directed at enumeration of fecal streptococci and enteric viruses with the BioHome waste water treatment system
County-Specific Net Migration by Five-Year Age Groups, Hispanic Origin, Race and Sex 2000-2010
This report documents the methodology used to prepare county-level, net migration estimates by five-year age cohorts and sex, and by race and Hispanic origin, for the intercensal period from 2000 to 2010. The estimates were prepared using a vital statistics version of the forward cohort residual method (Siegel and Hamilton 1952) following the techniques used to prepare the 1990 to 2000 net migration estimates (Voss, McNiven, Johnson, Hammer, and Fuguitt 2004) as described in detail below. These numbers (and the net migration rates derivable from them) extend the set of decennial estimates of net migration that have been produced following each decennial census beginning with 1960 (net migration for the 1950s: Bowles and Tarver, 1965; 1960s: Bowles, Beale and Lee, 1975; 1970s: White, Mueser and Tierney, 1987; 1980s: Fuguitt, Beale, and Voss 2010; and 1990s: Voss, McNiven, Hammer, Johnson and Fuguitt, 2004)
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