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We describe four new species in the genus Cymatodera Gray (Coleoptera: Cleridae: Tillinae): Cymatodera acuminata and Cymatodera unica from Mexico, Cymatodera parva from El Salvador and Honduras, and Cymatodera magdalena from Colombia. A distribution map of the new species is given. All relevant diagnostic characters are extensively figured and discussed. Finally, we include some biogeographic and taxonomic remarks for selected species.
Contrast sensitivity functions reveal information about a subject’s overall visual ability and have been investigated in several species of nonhuman primates (NHPs) with experimentally induced amblyopia and glaucoma. However, there are no published studies comparing contrast sensitivity functions across these species of normal NHPs. The purpose of this investigation was to compare contrast sensitivity across these primates to determine whether they are similar. Ten normal humans and eight normal NHPs (Macaca fascicularis) took part in this project. Previously published data from Macaca mulatta and Macaca nemestrina were also compared. Threshold was operationally defined as two misses in a row for a descending method of limits. A similar paradigm was used for the humans except that the descending method of limits was combined with a spatial, two-alternative forced choice (2-AFC) technique. The contrast sensitivity functions were fit with a double exponential function. The averaged peak contrast sensitivity, peak spatial frequency, acuity, and area under the curve for the humans were 268.9, 3.40 cpd, 27.3 cpd, and 2345.4 and for the Macaca fascicularis were 99.2, 3.93 cpd, 26.1 cpd, and 980.9. A two-sample t-test indicated that the peak contrast sensitivities (P = 0.001) and areas under the curve (P = 0.010) were significantly different. The peak spatial frequencies (P = 0.150) and the extrapolated visual acuities (P = 0.763) were not different. The contrast sensitivities for the Macaca fascicularis, Macaca mulatta, and Macaca nemestrina were qualitatively and quantitatively similar. The contrast sensitivity functions for the NHPs had lower peak contrast sensitivities and areas under the curve than the humans. Even though different methods have been used to measure contrast sensitivity in different species of NHP, the functions are similar. The contrast sensitivity differences and similarities between humans and NHPs need to be considered when using NHPs to study human disease.
OBJECTIVES/SPECIFIC AIMS: Identify objective neurological substrates of cognitive fatigue in Parkinson’s disease and in aging. METHODS/STUDY POPULATION: Structural and diffusion MRI. Behavioral assessments for aged adults and Parkinson’s disease. RESULTS/ANTICIPATED RESULTS: Gray and white matter deficits that correlate with deficits in the basal ganglia for fatigued Parkinson’s disease patients Versus anterior cingulate cortex in healthy aged adults with fatigue. DISCUSSION/SIGNIFICANCE OF IMPACT: Over 50% of patients with Parkison’s disease and 38% of healthy older adults suffer from cognitive fatigue. However, diagnostics are limited to subjective surveys and there are no treatments for either population. Therefore, objective measures are greatly needed for better diagnosis and development of treatment targets.
Gravitational interactions allow one to investigate the nature of matter in the universe independent of the properties that make it luminous. Much as studies of the dynamics of galaxies and clusters of galaxies have indicated the presence of dark matter, gravitational lensing provides an independent probe of the large scale distribution of dark matter in the universe.
Linear polarization measurements at milliarcsecond resolution have been made at λ6 cm using four stations of the U. S. VLBI Network and the Mark III recording system. Calibration of the cross-polarization contamination of the feeds was done using the cross- to parallel-hand fringe ratios of the essentially unpolarized source 0Q 208, and is believed accurate to 0.5%. Other sources, such as AO 0235+164 and 0106+013, which are nearly unresolved in the unpolarized fringes, show clear signs of resolution in their polarized fringes. A preliminary map of the BL Lacertae object OJ 287 is compatible with a weakly-polarized optically-thick core and a highly-polarized optically-thin jet about 5 mas in length.
An antenna in geostationary orbit was used for VLBI observations at 2.3 GHz, in combination with ground antennas in Australia and Japan. 23 of the 25 observed sources were detected on orbiter-ground baselines, with baseline lengths as large as 2.15 earth diameters. Brightness temperatures between 1012 K and 4 × 1012 K were measured for 10 sources.
Weeds are one of the most significant, and controllable, threats to crop production in North America. Monetary losses because of reduced soybean yield and decreased quality because of weed interference, as well as costs of controlling weeds, have a significant economic impact on net returns to producers. Previous Weed Science Society of America (WSSA) Weed Loss Committee reports, as chaired by Chandler (1984) and Bridges (1992), provided snapshots of the comparative crop yield losses because of weeds across geographic regions and crops within these regions after the implementation of weed control tactics. This manuscript is a second report from the current WSSA Weed Loss Committee on crop yield losses because of weeds, specifically in soybean. Yield loss estimates were determined from comparative observations of soybean yields between the weedy control and plots with greater than 95% weed control in studies conducted from 2007 to 2013. Researchers from each US state and Canadian province provided at least three and up to ten individual comparisons for each year, which were then averaged within a year, and then averaged over the seven years. These percent yield loss values were used to determine total soybean yield loss in t ha−1 and bu acre−1 based on average soybean yields for each state or province as well as current commodity prices for a given year as summarized by USDA-NASS (2014) and Statistics Canada (2015). Averaged across 2007 to 2013, weed interference in soybean caused a 52.1% yield loss. Based on 2012 census data in the US and Canada soybean was grown on 30,798,512 and 1,679,203 hectares with production of 80 million and 5 million tonnes, respectively. Using an average soybean price across 2007 to 2013 of US $389.81 t−1 ($10.61 bu−1), farm gate value would be reduced by US $16.2 billion in the US and $1.0 billion in Canada annually if no weed management tactics were employed.
Crop losses from weed interference have a significant effect on net returns for producers. Herein, potential corn yield loss because of weed interference across the primary corn-producing regions of the United States and Canada are documented. Yield-loss estimates were determined from comparative, quantitative observations of corn yields between nontreated and treatments providing greater than 95% weed control in studies conducted from 2007 to 2013. Researchers from each state and province provided data from replicated, small-plot studies from at least 3 and up to 10 individual comparisons per year, which were then averaged within a year, and then averaged over the seven years. The resulting percent yield-loss values were used to determine potential total corn yield loss in t ha−1 and bu acre−1 based on average corn yield for each state or province, as well as corn commodity price for each year as summarized by USDA-NASS (2014) and Statistics Canada (2015). Averaged across the seven years, weed interference in corn in the United States and Canada caused an average of 50% yield loss, which equates to a loss of 148 million tonnes of corn valued at over U.S.$26.7 billion annually.
The samples in this list were measured by the methane proportional counter method reported by Burke and Meinschein (1955). Shell samples were mechanically cleaned and washed with water. Where necessary, cold, very dilute HCI was used to remove the powdery exterior. Sedimentary wood and mud or clay samples were treated with hot concentrated HCI and washed with water before burning. Four other types of materials recovered from sediments were dated: (1) the total organic carbon, (2) benzene-soluble organic material, (3) foraminiferal tests, and (4) “dispersed carbonate”. The foraminiferal samples were recovered from the sediment by washing on a 120-mesh screen. These were then converted to carbon dioxide by acid treatment. “Dispersed carbonate” was recovered in the form of CO2, by acid (HCI) treatment of the sediment wash which had been depleted of Foraminifera. The total organic carbon samples were recovered by combustion to CO2 after all carbonates had been removed by acid treatment. Organic extractables were also converted to CO2 by combustion.
The radio source 0957+561 was identified by Walsh et al. (1979, Nature 279, pp.381–384) with a pair of quasars, 6.1 apart on the sky, whose optical emission and absorption spectra are nearly identical. Walsh et al. suggested a gravitational lens interpretation in which a single object is split into two images by an intervening massive object. Using the Very Large Array of the NRAO we have made a 6-cm wavelength radio map of 0957+561. The map shows unresolved sources of 36 and 30 mJy coincident with the optical N and S quasars, and a complex extended source of ~130 mJy (Roberts, Greenfield, and Burke: 1979, Science August 31). The extended emission lies on an arc containing the N quasar, and consists of two resolved sources containing 75 and 28 mJy, located 5.8 and 5.6 NE of the N quasar, a weak source of ~10 mJy about 5.5 SW of the N quasar, and a suggestion of a bridge connecting the NE and SW sources and the N quasar. There is no evidence of radio emission from a massive object between the two quasars. Although the existence of the extended source does not rule out a gravitational lens model for 0957+561, the underlying source required would have an unusual morphology. In addition, if the refracting object is at the redshift of the absorption seen in both quasars, its mass would have to be at least 2 × 1014 solar masses. Further observations at the VLA could rule out the gravitational lens model for 0957+561 if a second image corresponding to the NE extended component is not found.
Using an 8-meter Würzburg parabola on an equatorial mount in Washington, D. C., we have completed about half of the necessary observations and reductions for a survey of the 1420-Mc/s hydrogen emission for all sky areas near the galactic plane which are visible here.
The luminosity of the brightest Hiiregions of M31 was determined with the NRAO 3-element interferometer at 3.7 cm and 11 cm wavelength. It is unlikely that M31 has any superbright Hiiregions such as W51 or W49; our Galaxy has between 10 and 20 Hiiregions that are more luminous than any in M31.