13,668 research outputs found
Impact of varying analytical methodologies on grain particle size determination
No full textCitation: Kalivoda, J. R., Jones, C. K., & Stark, C. R. (2017). Impact of varying analytical methodologies on grain particle size determination. Journal of Animal Science, 95(1), 113-119. doi:10.2527/jas2016.0966The determination of particle size is an important quality control measurement for feed manufacturers, nutritionists, and producers. The current approved method for determining the geometric mean diameter by weight (d(gw)) and geometric standard deviation (S-gw) of grains is standard ANSI/ASAE S319.4. This method controls many variables, including the suggested quantity of initial material and the type, number, and size of sieves. However, the method allows for variations in sieving time, sieve agitators, and the use of a dispersion agent. The objective of this experiment was to determine which method of particle size analysis best estimated the particle size of various cereal grain types. Eighteen samples of either corn, sorghum, or wheat were ground and analyzed using different variations of the approved method. Treatments were arranged in a 5 x 3 factorial arrangement with 5 sieving methods: 1) 10-min sieving time with sieve agitators and no dispersion agent, 2) 10-min sieving time with sieve agitators and dispersion agent, 3) 15-min sieving time with no sieve agitators or dispersion agent, 4) 15-min sieving time with sieve agitators and no dispersion agent, and 5) 15-min sieving time with sieve agitators and dispersion agent conducted in 3 grain types (ground corn, sorghum, and wheat) with 4 replicates per treatment. The analytical method that resulted in the lowest dgw and greatest Sgw was considered desirable because it was presumably representative of increased movement of particles to their appropriate sieve. Analytical method affected dgw and Sgw (P 0.05), but wheat ground using the same mill parameters was 120 to 104 m larger (P = 0.05) than corn and sorghum, respectively. Both sieve agitators and dispersion agent should be included when conducting particle size analysis. The results indicate that 10 and 15 min of sieving time produced similar results
Alloperla natchez Surdick & Stark
No full text<i>Alloperla natchez</i> Surdick & Stark <p>(Figs. 25-30)</p> <p> <i>Alloperla natchez</i> Surdick & Stark, 1980:71.</p> <p>Holotype ♂ (United States National Museum), Little Sand Creek, Natchez Trace Parkway, Claiborne Co., Mississippi</p> <p> <i>Alloperla natchez</i>: Brown & Stark, 1995:122. Description of nymph and egg</p> <p> <i>Alloperla natchez</i>: Hardy et al., 1994:368. Distribution <i>Alloperla natchez</i>: Surdick, 2004:18. Redescription</p> <p> <b>Material examined.</b> MS: Claiborne Co., Ragsdale Creek, Regan Rd, 17 April 1993, B. Stark, 9 ♂, 7 ♀ (BPS). Franklin Co., Mill Branch, Homochitto National Forest, 14 May 1993, N. Phiefer, 2 ♂, 19 ♀ (BPS). Franklin Co., tributary of Porter Creek, 13 April 1993, C. Hardy, C. Boll, 9 ♂, 6 ♀ (BPS). Smith Co., Clear Creek, 3 mi SW Mize, 24 April 1991, B. Stark, D. Tanner, 1 ♂, 5 ♀ (BPS).</p> <p> <b>Epiproct.</b> Length from base to fork, ca. 101 μm. Greatest pre-apical width, ca. 28 μm; apical width, ca. 27 μm. Cowl reaching almost to base of epiproct fork (Figs. 25-26). Epiproct dorsum completely bare (Figs. 27, 30), but apical third armed with irregular lateral rows of large, ventrolaterally directed setae (Figs. 26- 29). Width relatively uniform from base to beyond midlength, but gradually narrowed in apical third to base of fork (Figs. 26-27). Arms of fork project downward in lateral and frontal aspects (Figs. 28-29).</p>Published as part of <i>Willett, Michele R. & Stark, Bill P., 2009, The Alloperla Leonarda Group Of Eastern North America, With Sem Images Of Four Out-Group Species (Plecoptera: Chloroperlidae), pp. 108-127 in Illiesia 5 (11)</i> on page 112, DOI: <a href="http://zenodo.org/record/4759290">10.5281/zenodo.4759290</a>
Perlesta nelsoni Stark 1989
No full textPerlesta nelsoni Stark 1989 Amherst Co. Otter Creek, above culvert, Blue Ridge Parkway, 17-18, July 2007, C. R. Parker, 2♂, 4♀ (CSUC); Floyd Co., Blue Ridge Parkway, MP 146.0, 18-19 July 2007, C. R. Parker, 2♀ (CSUC); Patrick Co. Little Rock Castle Creek, Blue Ridge Parkway, MP 165.3, 18-19 July 2007, C. R. Parker, 3♀ (CSUC). Originally described from North Carolina, South Carolina, and Tennessee (Stark 1989), P. nelsoni is apparently a widespread species of the higher Appalachians and has been recorded as far north as New York (Myers et al. 2011).Published as part of Kondratieff, Boris C., Zuellig, Robert E. & Lenat, David R., 2011, A New Species Of Perlesta (Plecoptera: Perlidae) From North Carolina With Additional Records For North Carolina And Virginia, pp. 297-301 in Illiesia 7 (27) on page 300, DOI: 10.5281/zenodo.475321
C. R. Stark
No full textC. R. Starkhttps://scholarsjunction.msstate.edu/ua-photo-collection/5978/thumbnail.jp
Elastic turbulence in two-dimensional Taylor-Couette flows
No full textWe report the onset of elastic turbulence in a two-dimensional Taylor-Couette geometry using numerical solutions of the Oldroyd-B model generated with the program OpenFOAM®. Beyond a critical Weissenberg number, an elastic instability causes a supercritical transition from the laminar Taylor-Couette flow to a turbulent flow. The order parameter, the time average of secondary-flow strength, follows the scaling law with and . Additionally, the flow resistance increases beyond Wic. The temporal power spectra of the velocity fluctuations show a power-law decay with a characteristic exponent in the range , associated with elastic turbulence, for all
Hamster cells with increased rates of DNA amplification, a new phenotype.
No full textBaby hamster kidney (BHK) cells selected simultaneously with N-phosphonacetyl-L-aspartate (PALA) and methotrexate (MTX) gave rise to doubly resistant colonies at frequencies 20 to 260 times greater than the product of the independent frequencies found with PALA or MTX alone. Double resistance was due to amplification of both target genes, CAD and DHFR. Four independent doubly resistant "MP" lines were selected and characterized. Cells resistant to coformycin, pyrazofurin, or ouabain were generated from all four MP lines at rates up to 25 times greater than the rates for BHK cells. These three drugs select cells that have amplified the genes for their target enzymes. Therefore, we conclude that the four MP lines have an amplificator phenotype. All four grew much more slowly than BHK cells, indicating that the amplificator phenotype may be linked to significant defects in metabolism or cell division
Anacroneuria quilla Stark & Zuniga 1999
No full textAnacroneuria quilla Stark & Zúñiga Anacroneuria quilla Stark & Zúñiga in Stark et al., 1999:35. Holotype ♂, Termales de Santa Rosa de Cabal, Risaralda, Colombia (USNM) Material examined. COLOMBIA: 3♂, Risaralda, Municipio Santa Rosa de Cabal, Vereda San José de la Paloma, Parque Municipal Natural Campoalegre, Río San Eugenio headwater basin, 2100 m, N 04 ° 49 ′ 49 ″, W 75 ° 34 ′ 12 ″, 17-19 May 2006, W. Cardona (MEUV, BPS). 3♂, Risaralda, Municipio de Pereira, Parque Nacional Natural Los Nevados, El Jordán, Río Otún headwater basin, 3100 m N 04 ° 42 ′ 32 ″, W 75 ° 29 ′ 37 ″, 27-28 June 2006, M. del C. Zúñiga, W. Cardona, G. Zabala, R. J. Cardozo-Zúñiga (MEUV, BPS). 2♂, Risaralda, Municipio de Pereira, Parque Regional Natural Ucumarí, El Cedral, Río Otún middle basin, 2060 m, N 04 ° 42 ′ 17 ″, W 75 ° 32 ′ 21 ″, 30 June 2006, M. del C. Zúñiga, W. Cardona, G. Zabala, R. J. Cardozo-Zúñiga (MEUV). 4♂, Risaralda, Municipio de Pereira, Parque Natural Regional Ucumarí, Estación La Pastora, Río Otún metallic bridge, 2350 m, N 04 ° 42 ′ 35 ″, W 75 ° 30 ′ 03 ″, 5 July 2007, M. del C. Zúñiga, W. Cardona, J. Chará, L. P. Giraldo, A. M. Chará (MEUV, UM-ICN, MEUA). 1♂, Risaralda, Municipio de Santuario, Parque Municipal Natural Planes de San Rafael, Río San Rafael headwater basin, bridge, 2050 m, N 05 ° 07 ′ 38 ″, W 76 ° 00 ′ 08 ″, 15-16 July 2007, M. del C. Zúñiga, W. Cardona, A. Laina, G. Zabala, C. Cultid (MEUV). 1♂, Risaralda, Municipio de Pereira, Vereda La Suiza, Santuario de Fauna y Flora Otún-Quimbaya, Río Otún middle basin, Finca Buenos Aires bridge, 1800 m, N 04 ° 44 ′ 00 ″, W 75 ° 34 ′ 49 ″, 12 April 2006, M. del C. Zúñiga, W. Cardona, G. Zabala (MEUV). 1♂, same data, except 1830 m, N 04 ° 43 ′ 42 ″, W 75 ° 34 ′ 25 ″, emerging, 22 April 2006, W. Cardona, C. Cultid (BYU). Discussion. This species was previously reported from Caldas, Cauca, Risaralda and Valle del Cauca in Colombia and from Ecuador (Stark et al. 1999; Stark 2001; Zúñiga & Stark 2002; Zúñiga et al. 2006). The species appears to be relatively common over a broad range of the Cordillera Occidental and Cordillera Central, but these specimens represent the third report from Risaralda, mainly in protected areas and at the highest altitudes known in the mountains of the Los Nevados National Park.Published as part of Zúñiga, Maria del Carmen, Stark, Bill P., Cardona, William, Tamaris-Turizo, César & Ortega, Oscar E., 2007, Additions To The Colombian Anacroneuria Fauna (Plecoptera: Perlidae) With Descriptions Of Seven New Species, pp. 127-149 in Illiesia 3 (13) on page 143, DOI: 10.5281/zenodo.475466
\u27Jubilee of Progress, Stephen D. Lee, C. R. Stark, B. M. Duggar, I. D. Sessums\u27
No full text\u2775 Years at Mississippi State College-Some of the people pictured are: Stephen Lee, C. R. Stark, Dr. B. M. Duggar, and Major I. D. Sessums\u27https://scholarsjunction.msstate.edu/ua-photo-collection/1558/thumbnail.jp
SUBMILLIMETER LASER STARK SPECTROSCOPY SYSTEM
No full textAuthor Institution: Department of Physics, University of Idaho; Department of Computer Science, University of Waterloo; Hughes Aircraft Co., P.O.B. 92919 S/C Building 541, Mail Station B326, Los Angeles, CA 90009; P.O.B. 8729, MoscowA Stark spectrometer and laser system has been developed which can measure Stark spectra of polar molecules with an absorptivity sensitivity of . The accuracy for determining transition frequencies is about one MHz. The Stark plates are made of silvered glass, 60 cm long, spaced 0.05 cm. Stark fields to 60 KV/cm are used. The Stark field is square-wave modulated at 20 Hz. The detector is a Golay cell with quartz window and polyethylene lens optics. The laser is a direct discharge type, using HCN or DCN, at . Source gases are cyanogen. , and or , flowing about 10 std per minute each. Plano-concave mirror geometry is used, . Inter-mirror distance is 3.7 meters; tube diameter = 10 cm. Mirrors are ground from OFHC copper. Spectral sensitivity is due primarily to stability of laser plasma, and to management of ``brown polymer'' deposit
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