335 research outputs found
Clingfishes (Gobiesocidae) from Belize and Honduras, Central America, with a Redescription of Gobiesox barbatulus Starks
Six marine species and a single freshwater species of clingfish are reported from collections made by the authors in Belize and Honduras, Central America, during the period 1970 through 1980. Acyrtops amplicirrus Briggs, Acyrtus rubiginosus (Poey), and Gobiesox barbatulus Starks are reported for the first time from the western Caribbean and Gobiesox nudus (Linnaeus) is recorded for the first time from Honduras. Acyrtops amplicirrus is tentatively recognized as distinct from A. beryllina (Hildebrand and Ginsburg). Gobiesox barbatulus Starks is distinguished from G. strumosus on the basis of development of barbels on the pre- and suborbital areas, fringing of the dermal flaps on the anterior nostrils, and more numerous and narrow lines radiating from the eye in the case of G. barbatulus. Principal components analysis of 13 morphometric characters resulted in clear separation of the two forms along the first component axis. Both species are mainland forms occurring in turbid and often brackish water. Gobiesox barbatulus is a southern form occurring from Brazil to Belize, G. strumosus is a northern form occurring from Campeche, Mexico to Virginia. The apparent distributional boundary (centered on east coast of the Yucatan Peninsula, Mexico) between the two agrees with the boundary between the northern and southern continental shorefish faunas recognized by Robins (1971) and Gilbert (1973)
Eviota lentiginosa, a new dwarfgoby from Norfolk Island, Australia (Teleostei: Gobiidae).
A new endemic species of dwarfgoby, Eviota lentiginosa n. sp., is described from Norfolk Island, an isolated island 1400 km east of the Australian mainland. The new species is distinguished by having the cephalic sensory-canal pore system with only the IT pore lacking (Pattern 2); a flat, rounded, plate-like male urogenital papilla; the dorsal/anal fin-ray formula 8/8; all pectoral-fin rays apparently unbranched; the fifth pelvic-fin ray absent; a dark spot on the lower half of the pectoral-fin base; and the body color yellow with a peppering of small brown melanophores in life. It is the sixth species of Eviota known from Norfolk Island
Eviota algida, a new dwarfgoby species from the upwelling waters off Nusa Penida, Indonesia (Teleostei: Gobiidae)
A new species of dwarfgoby, Eviota algida, with a complete cephalic sensory-canal pore pattern (pattern I), a dorsal/anal-fin formula usually 8/8, pectoral-fin rays branched, 5th pelvic-fin ray absent, anterior dorsal-fin spines filamentous in males, a subcutaneous dark spot at center of caudal peduncle over preural centrum, male urogenital papilla black, and a red eye with gold specks, is described from a deep, cold-water upwelling area off Nusa Penida Island, Bali, Indonesi
Bioplastic (PHBV) addition to soil alters microbial community structure and negatively affects plant-microbial metabolic functioning in maize
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Category Fluency Test: Normative Data for English- and Spanish-Speaking Elderly
Category fluency tasks are an important component of neuropsychological assessment, especially when evaluating for dementia syndromes. The growth in the number of Spanish-speaking elderly in the United States has increased the need for appropriate neuropsychological measures and normative data for this population. This study provides norms for English and Spanish speakers, over the age of 50, on 3 frequently used measures of category fluency: animals, vegetables, and fruits. In addition, it examines the impact of age, education, gender, language, and depressed mood on total fluency scores and on scores on each of these fluency measures. A sample of 702 cognitively intact elderly, 424 English speakers, and 278 Spanish speakers, participated in the study. Normative data are provided stratified by language, age, education, and gender. Results evidence that regardless of the primary language of the examinee, age, education, and gender are the strongest predictors of total category fluency scores, with gender being the best predictor of performance after adjusting for age and education. English and Spanish speakers obtained similar scores on animal and fruit fluency, but English speakers generated more vegetable exemplars than Spanish speakers. Results also indicate that different fluency measures are affected by various factors to different degrees. (JINS, 2000, 6, 760–769.
Radio Astronomy
Contains research objectives and summary of research on seven research projects.M.I.T. Sloan Fund for Basic ResearchNational Aeronautics and Space Administration (Contract NAS5-21980)National Aeronautics and Space Administration (Contract NAS5-22485)National Aeronautics and Space Administration (Contract NAS5-23677)National Aeronautics and Space Administration (Contract NAS5-22929)U. S. Air Force - Electronic Systems Division (Contract F19628-75-C-0122)National Science Foundation (Grant AST73-05043-A02)National Science Foundation (Grant AST73-05042-A03
JWST Optical Telescope Element Center of Curvature Test
The James Webb Space Telescope (JWST) Optical Telescope Element (OTE) and Integrated Science Instrument Module (ISIM) completed element level integration and test programs and were integrated to the next level of assembly called OTE/ISIM (OTIS) at Goddard Space Flight Center (GSFC) in Greenbelt, Maryland in 2016. Before shipping the OTIS to Johnson Space Center (JSC) for optical test at cryogenic temperature a series of vibration and acoustic tests were performed. To help ensure that the OTIS was ready to be shipped to JSC an optical center of curvature (CoC) test was performed to measure changes in the mirror's optical performance to verify that the telescope's primary mirror was not adversely impacted by the environmental testing and help us in understanding potential anomalies identified during the JSC tests. The primary is a 6.5 meter diameter mirror consisting of 18 individual hexagonal segments. Each segment is an off-axis asphere. There are a total of three prescriptions repeated six times each. As part of the CoC test each segment was individually measured using a high-speed interferometer (HSI) designed and built specifically for this test. This interferometer is capable of characterizing both static and dynamic characteristics of the mirrors. The latter capability was used, with the aid of a vibration stinger applying a low-level input force, to measure the dynamic characteristic changes of the PM backplane structure. This paper describes the CoC test setup and both static and dynamic test results
Five anthropogenic factors that will radically alter forest conditions and management needs in the Northern United States
The Northern United States includes the 20 states bounded by Maine, Maryland, Missouri, and Minnesota. With 70 million ha of forestland and 124 million people, it is the most densely forested (42% of land area) and most densely populated (74 people/km2) quadrant of the United States. Three recent, large-scale, multiresource assessments of forest conditions provide insight about trends and issues in the North, and collectively these and other supporting documents highlight factors that will be extraordinarily influential in large-scale northern forest management needs over the next 50 years. This review article discusses five of those factors: (1) northern forests lack age-class diversity and will uniformly grow old without management interventions or natural disturbances, (2) the area of forestland in the North will decrease as a consequence of expanding urban areas, (3) invasive species will alter forest density, diversity, and function, (4) management intensity for timber is low in northern forests and likely to remain so, and (5) management for nontimber objectives will gain relevance but will be challenging to implement. Suggested actions to address these factors include the following: develop quantifiable state and regional goals for forest diversity, understand the spatial and structural impacts of urban expansion on forests, develop symbiotic relationships among forest owners, forest managers, forest industry and the other stakeholders to support contemporary conservation goals, and work to understand the many dimensions of forest change. In the next several decades, climate change seems unlikely to overwhelm or negate any of the five factors discussed in this article; rather it will add another complicating dimension.Natural Resource Ecology and Managemen
Evaluating The National Land Cover Database Tree Canopy and Impervious Cover Estimates Across the Conterminous United States: A Comparison with Photo-Interpreted Estimates
The 2001 National Land Cover Database (NLCD) provides 30-m resolution estimates of percentage tree canopy and percentage impervious cover for the conterminous United States. Previous estimates that compared NLCD tree canopy and impervious cover estimates with photo-interpreted cover estimates within selected counties and places revealed that NLCD underestimates tree and impervious cover. Based on these previous results, a wall-to-wall comprehensive national analysis was conducted to determine if and how NLCD derived estimates of tree and impervious cover varies from photo-interpreted values across the conterminous United States. Results of this analysis reveal that NLCD significantly underestimates tree cover in 64 of the 65 zones used to create the NCLD cover maps, with a national average underestimation of 9.7% (standard error (SE) = 1.0%) and a maximum underestimation of 28.4% in mapping zone 3. Impervious cover was also underestimated in 44 zones with an average underestimation of 1.4% (SE = 0.4%) and a maximum underestimation of 5.7% in mapping zone 56. Understanding the degree of underestimation by mapping zone can lead to better estimates of tree and impervious cover and a better understanding of the potential limitations associated with NLCD cover estimates
Global regularity in ultradifferentiable classes
Se estudia la w-regularidad de soluciones de ciertos operadores que son globalmente hipoelípticos en el toro N-dimensional. Se aplican estos resultados para probar la w-regularidad global de ciertas clases de sublaplacianos. En este sentido, se extiende trabajo previo en el contexto de la clases analíticas y de Gevrey. Se dan varios ejemplos de w-hipoelipticidad local y global.The research of the authors was partially supported by MEC and FEDER Project MTM2010-15200.Albanese, AA.; Jornet Casanova, D. (2014). Global regularity in ultradifferentiable classes. Annali di Matematica Pura ed Applicata. 193(2):369-387. https://doi.org/10.1007/s10231-012-0279-5S3693871932Albanese A.A., Jornet D., Oliaro A.: Quasianalytic wave front sets for solutions of linear partial differential operators. Integr. Equ. Oper. 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