321 research outputs found

    Statistical analyses of hemp cannabinoid test results

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    Cannabis sativa L. is a flowering plant used for recreational and industrial purposes that produces a class of compounds called cannabinoids. Industrial hemp is a strain of Cannabis sativa L. that has been propagated to have a low Δ 9 tetrahydrocannabinol (Δ 9 THC) and a high cannabidiol (CBD) content. With recent advancements in legislation, farms are now growing hemp for fiber, CBD production and other hemp derived product purposes but crops risk being destroyed if THC content levels exceed the current maximum legal limit of 0.3%. For the present study hemp samples were dried, ground, extracted with various alcohols, filtered, and assayed by ultra-High Pressure Liquid Chromatography with ultraviolet detection (uHPLC-UV) and Gas Chromatography with flame ionization detection (GC-FID) for ten cannabinoids, with primary focus on THC and CBD. Three replicates were done for each sample strictly following published protocols. We have found that the results of analyses vary considerably due to variations in cannabinoid content in plant biomass, different hemp varieties, growing location and before/after drying. The random sampling procedure, the heterogeneity of the crop and large standard deviations for analyses affected results. We have statistically evaluated data and conclude that large sample standard deviations are intrinsic with the protocols. These may lead to crops that are actually within the legal limit being destroyed by regulators. As a result, it was concluded that either 0.3% THC should not be applied as an absolute value for legality but should be associated with sample standard deviation for replicates of analyses, or the absolute criterion be raised to 0.5%

    Pearl millet parental lines 843A and 843B

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    Pearl millet (Pennisetum glaucum) parental line 843B was developed by 9 generations of pedigree selection of the backcross of Tift23D2B1 to PI185542. Line 843A was derived by backcrossing PI185642 × Tift23D2A1 to Tift23D2A1. Both lines are short-statured d2 dwarf lines, averaging 42 days to 50% flowering in India during the rainy season. Plants produce 3-4 candle-shaped panicles with large grains (11-12 g 1000-grain weight) and grey colour. Line 843A is the seed parent of early-maturing hybrid HHB67

    Pearl Millet Parental Lines 842A and 842B

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    Pearl millet (Pennisetum glaucum) parental maintainer line 842B and male sterile line 842 A were derived by pedigree selection from the second backcross of Tift23D2B1 to PI185642 and from 4 generations of backcrossing of PI185642 to Tift23D2A1, respectively, at Kansas State University. Line 842A has stable male sterility across seasons and sites, carries the d2 dwarfing gene, is early maturing and produces 12-3 candle-shaped panicles. It is the seed parent of several hybrid varieties, including HHB68 and a dwarf variety

    Milliarcsecond angular resolution of reddened stellar sources in the vicinity of the Galactic Center

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    For the first time, the lunar occultation technique has been employed on a very large telescope in the near-IR with the aim of achieving systematically milliarcsecond resolution on stellar sources. We have demonstrated the burst mode of the ISAAC instrument, using a fast read-out on a small area of the detector to record many tens of seconds of data at a time on fields of few squared arcsec. We have used the opportunity to record a large number of LO events during a passage of the Moon close to the Galactic Center in March 2006. We have developed a data pipeline for the treatment of LO data, including the automated estimation of the main data analysis parameters using a wavelet-based method, and the preliminary fitting and plotting of all light curves. We recorded 51 LO events over about four hours. Of these, 30 resulted of sufficient quality to enable a detailed fitting. We detected two binaries with subarcsec projected separation and three stars with a marginally resolved angular diameter of about 2 mas. Two more SiO masers, were found to be resolved and in one case we could recover the brightness profile of the extended emission, which is well consistent with an optically thin shell. The remaining unresolved stars were used to characterize the performance of the method. The LO technique at a very large telescope is a powerful and efficient method to achieve angular resolution, sensitivity, and dynamic range that are among the best possible today with any technique. The selection of targets is naturally limited and LOs are fixed-time events, however each observation requires only a few minutes including overheads. As such, LOs are ideally suited to fill small gaps of idle time between standard observations.Comment: A&A in pres

    Performance limitations of small-format high-speed infrared arrays for active control loops in interferometry and adaptive optics

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    The detector mounted in the VLTI fringe sensor FINITO is a 256x256 HgCdTe array with a cut-off wavelength of 1.9 micron. The same arrays having cut-off wavelengths of 2.5 micron will be used in the tip tilt sensor IRIS and the PRIMA instrument of the VLT interferometer. The arrays are part of an active control loop with integration times as short as a few hundred microseconds. The fringe tracker FINITO uses only 7 pixels of the array. To take advantage of the four parallel channels of the PICNIC multiplexer, the pixels illuminated in each quadrant are positioned at the same location within the quadrants. A noise analysis of the PICNIC array shows that the main sensitivity limitation of the array is contained in the low frequency part of the noise power spectrum. Similar behaviour has been observed with other infrared arrays. In an effort to optimize the unit cell pixel buffer to achieve high speed and low noise, a prototype multiplexer is being developed at Rockwell for adaptive optics. However, low frequency noise may still be the limiting factor dominating the noise performance of infrared arrays. To overcome this noise barrier, detector architectures have to be envisaged which should allow double correlated sampling on shorter time scales than a full exposure. This might be accomplished by some kind of gate in the IR material which allows charge to be shifted from an integrating well in the infrared pixel to a small sensing node capacitance of the multiplexer unit cell buffer

    An overview of the mid-infrared spectro-interferometer MATISSE: science, concept, and current status

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    MATISSE is the second-generation mid-infrared spectrograph and imager for the Very Large Telescope Interferometer (VLTI) at Paranal. This new interferometric instrument will allow significant advances by opening new avenues in various fundamental research fields: studying the planet-forming region of disks around young stellar objects, understanding the surface structures and mass loss phenomena affecting evolved stars, and probing the environments of black holes in active galactic nuclei. As a first breakthrough, MATISSE will enlarge the spectral domain of current optical interferometers by offering the L and M bands in addition to the N band. This will open a wide wavelength domain, ranging from 2.8 to 13 um, exploring angular scales as small as 3 mas (L band) / 10 mas (N band). As a second breakthrough, MATISSE will allow mid-infrared imaging - closure-phase aperture-synthesis imaging - with up to four Unit Telescopes (UT) or Auxiliary Telescopes (AT) of the VLTI. Moreover, MATISSE will offer a spectral resolution range from R ~ 30 to R ~ 5000. Here, we present one of the main science objectives, the study of protoplanetary disks, that has driven the instrument design and motivated several VLTI upgrades (GRA4MAT and NAOMI). We introduce the physical concept of MATISSE including a description of the signal on the detectors and an evaluation of the expected performances. We also discuss the current status of the MATISSE instrument, which is entering its testing phase, and the foreseen schedule for the next two years that will lead to the first light at Paranal.Comment: SPIE Astronomical Telescopes and Instrumentation conference, June 2016, 11 pages, 6 Figure

    Dbf2–Mob1 drives relocalization of protein phosphatase Cdc14 to the cytoplasm during exit from mitosis

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    Exit from mitosis is characterized by a precipitous decline in cyclin-dependent kinase (Cdk) activity, dissolution of mitotic structures, and cytokinesis. In Saccharomyces cerevisiae, mitotic exit is driven by a protein phosphatase, Cdc14, which is in part responsible for counteracting Cdk activity. Throughout interphase, Cdc14 is sequestered in the nucleolus, but successful anaphase activates the mitotic exit network (MEN), which triggers dispersal of Cdc14 throughout the cell by a mechanism that has remained unknown. In this study, we show that a MEN component, protein kinase Dbf2–Mob1, promotes transfer of Cdc14 to the cytoplasm and consequent exit from mitosis by direct phosphorylation of Cdc14 on serine and threonine residues adjacent to a nuclear localization signal (NLS), thereby abrogating its NLS activity. Our results define a mechanism by which the MEN promotes exit from mitosis
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