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961.
Lebude AV White SA Fulcher AF Frank S Klingeman Iii WE Chong JH Chappell MR Windham A Braman K Hale F Dunwell W Williams-Woodward J Ivors K Adkins C Neal J 《Pest management science》2012,68(9):1278-1288
BACKGROUND: The Southern Nursery Integrated Pest Management (SNIPM) working group surveyed ornamental nursery crop growers in the southeastern United States to determine their pest management practices. Respondents answered questions about monitoring practices for insects, diseases and weeds, prevention techniques, intervention decisions, concerns about IPM and educational opportunities. Survey respondents were categorized into three groups based on IPM knowledge and pest management practices adopted. RESULTS: The three groups differed in the use of standardized sampling plans for scouting pests, in monitoring techniques, e.g. sticky cards, phenology and growing degree days, in record‐keeping, in the use of spot‐spraying and in the number of samples sent to a diagnostic clinic for identification and management recommendation. CONCLUSIONS: Stronger emphasis is needed on deliberate scouting techniques and tools to monitor pest populations to provide earlier pest detection and greater flexibility of management options. Most respondents thought that IPM was effective and beneficial for both the environment and employees, but had concerns about the ability of natural enemies to control insect pests, and about the availability and effectiveness of alternatives to chemical controls. Research and field demonstration is needed for selecting appropriate natural enemies for augmentative biological control. Two groups utilized cooperative extension almost exclusively, which would be an avenue for educating those respondents. Copyright © 2012 Society of Chemical Industry 相似文献
962.
Maya astronomical tables are recognized in bark-paper books from the Late Postclassic period (1300 to 1521 C.E.), but Classic period (200 to 900 C.E.) precursors have not been found. In 2011, a small painted room was excavated at the extensive ancient Maya ruins of Xultun, Guatemala, dating to the early 9th century C.E. The walls and ceiling of the room are painted with several human figures. Two walls also display a large number of delicate black, red, and incised hieroglyphs. Many of these hieroglyphs are calendrical in nature and relate astronomical computations, including at least two tables concerning the movement of the Moon, and perhaps Mars and Venus. These apparently represent early astronomical tables and may shed light on the later books. 相似文献
963.
Smith DE Zuber MT Phillips RJ Solomon SC Hauck SA Lemoine FG Mazarico E Neumann GA Peale SJ Margot JL Johnson CL Torrence MH Perry ME Rowlands DD Goossens S Head JW Taylor AH 《Science (New York, N.Y.)》2012,336(6078):214-217
Radio tracking of the MESSENGER spacecraft has provided a model of Mercury's gravity field. In the northern hemisphere, several large gravity anomalies, including candidate mass concentrations (mascons), exceed 100 milli-Galileos (mgal). Mercury's northern hemisphere crust is thicker at low latitudes and thinner in the polar region and shows evidence for thinning beneath some impact basins. The low-degree gravity field, combined with planetary spin parameters, yields the moment of inertia C/MR(2) = 0.353 ± 0.017, where M and R are Mercury's mass and radius, and a ratio of the moment of inertia of Mercury's solid outer shell to that of the planet of C(m)/C = 0.452 ± 0.035. A model for Mercury's radial density distribution consistent with these results includes a solid silicate crust and mantle overlying a solid iron-sulfide layer and an iron-rich liquid outer core and perhaps a solid inner core. 相似文献
964.
Tenaillon O Rodríguez-Verdugo A Gaut RL McDonald P Bennett AF Long AD Gaut BS 《Science (New York, N.Y.)》2012,335(6067):457-461
To estimate the number and diversity of beneficial mutations, we experimentally evolved 115 populations of Escherichia coli to 42.2°C for 2000 generations and sequenced one genome from each population. We identified 1331 total mutations, affecting more than 600 different sites. Few mutations were shared among replicates, but a strong pattern of convergence emerged at the level of genes, operons, and functional complexes. Our experiment uncovered a set of primary functional targets of high temperature, but we estimate that many other beneficial mutations could contribute to similar adaptive outcomes. We inferred the pervasive presence of epistasis among beneficial mutations, which shaped adaptive trajectories into at least two distinct pathways involving mutations either in the RNA polymerase complex or the termination factor rho. 相似文献
965.
MT Maurano R Humbert E Rynes RE Thurman E Haugen H Wang AP Reynolds R Sandstrom H Qu J Brody A Shafer F Neri K Lee T Kutyavin S Stehling-Sun AK Johnson TK Canfield E Giste M Diegel D Bates RS Hansen S Neph PJ Sabo S Heimfeld A Raubitschek S Ziegler C Cotsapas N Sotoodehnia I Glass SR Sunyaev R Kaul JA Stamatoyannopoulos 《Science (New York, N.Y.)》2012,337(6099):1190-1195
966.
Andres M. Agostinelli Anthony J. Clark Gina Brown-Guedira David A. Van Sanford 《Euphytica》2012,186(1):115-126
Fusarium head blight (FHB), or head scab, is an economically important disease of wheat (Triticum aestivum L.). In developing FHB-resistant soft winter wheat cultivars, breeders have relied on phenotypic selection, marker assisted
selection (MAS), or a combination of the two. The objectives of this study were to estimate heritability of resistance in
a resistant × susceptible cross and to simulate selection in order to determine the optimal combination of phenotypic and
genotypic selection. F2 derived lines from the cross of KY93C-1238-17-2 (high yielding, susceptible) × VA01W-476 (resistant line with two exotic
quantitative trait loci (QTL) and additional resistance) were grown under artificial inoculation in scab nurseries at Lexington
(2007 and 2008) and Princeton (2008), KY. Visual symptoms were estimated on a 1–3 scale; percentage Fusarium damaged kernels
(FDK), and deoxynivalenol (DON) concentration were measured. VA01W-476 contributed resistance alleles at two major QTL: Fhb1 and a QTL on chromosome 2DL, QFhs.nau-2DL. In this genetic background, the effect of QFhs.nau-2DL was more pronounced than that of Fhb1: 55 vs. 25% DON reduction and 40 vs. 32% FDK reduction. Genotypic selection based on both QTL was equivalent to phenotypic
selection of the most resistant 28% of the population for DON and the most resistant 24% of the population for FDK. We propose
that an initial round of phenotypic selection at moderate selection intensity will enrich the population with major QTL resistance
alleles while maintaining variation at minor scab resistance loci and for other traits in general. Genotyping can then be
used to extract lines whose phenotypic worth has been demonstrated and which are homozygous for resistance alleles at the
major QTL. 相似文献
967.
Kvitko-White H Balog K Scott-Moncrieff JC Johnson A Lantz GC 《Journal of the American Animal Hospital Association》2012,48(1):60-65
A 4 yr old spayed female Labrador retriever was referred for acute respiratory distress and was found to have bilateral laryngeal paralysis. Physical examination and biochemical testing were consistent with systemic lupus erythematosus (SLE) and did not reveal a likely alternative cause for the laryngeal paralysis. Following immunosuppressive and supportive treatment, the dog regained normal laryngeal function. At a scheduled follow-up examination 6 wk later, normal laryngeal function was confirmed via sedated laryngeal examination. Laryngeal paralysis associated with SLE has been reported in humans, but this is the first known report of acquired laryngeal paralysis associated with SLE in the dog. 相似文献
968.
Hsu K Snead E Davies J Carr A 《Journal of the American Animal Hospital Association》2012,48(3):209-215
An 8 yr old male English bulldog receiving treatment for immune-mediated thrombocytopenia was diagnosed with calcinosis cutis 90 days after initiation of corticosteroid therapy. Twenty-four days later, the patient presented in a comatose state after collapsing and was euthanized. Postmortem examination revealed coronary arteriosclerosis and myocardial infarction leading to congestive heart failure. Calcinosis cutis and myocardial necrosis were most likely complications associated with administration of corticosteroids in this dog. Important implications regarding the classification of calcinosis cutis and the use of immunosuppressive doses of corticosteroids are discussed. 相似文献
969.
Benjamin J. Schlegel Victoria J. Nowell Valeria R. Parreira Glenn Soltes John F. Prescott 《Canadian journal of veterinary research》2012,76(4):248-254
This study examined known or possible virulence-associated genes in type A Clostridium perfringens from cases of both bovine clostridial abomasitis (BCA) and jejunal hemorrhage syndrome (JHS) and compared these to isolates from calves that were healthy or had undifferentiated diarrheal illness. A real-time polymerase chain reaction (PCR) assay was used to genotype the 218 C. perfringens isolates. Isolates were sourced from healthy and diarrheic young and mature cattle (n = 191), from calves with confirmed or suspected BCA (n = 22), and from mature cattle with JHS (n = 5). Of 216 isolates (96%), 208 were positive for the cpa gene and 13% (29/218) were positive for atypical cpb2. Three of 8 (37.5%) confirmed BCA isolates, 2 of 13 (15.4%) suspected BCA isolates, and no JHS isolates tested positive for atypical cpb2. As all isolates were negative for cpb, cpb2, cpe, etx, netB, and tpeL, the results of the present study do not support a role for these genes in BCA or JHS. A subset of unique genes identified in 1 bovine clostridial abomasitis isolate (F262), for which a genome sequence is available, was searched for in 8 BCA isolates by PCR. None of the 10 genes was consistently present in all or even in a majority of BCA isolates. Many of these genes were also variably and inconsistently present in type A isolates from calves that did not have BCA. Although a virulence signature to aid in the diagnosis of BCA caused by C. perfringens type A was not identified, further work may discover a gene or group of genes that would constitute such a signature. 相似文献
970.
Sandra Manfra Marretta Maureen Leesman Anthony Burgess-Cassler G. David McClure Jr. Mary Buelow Misty Finn 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(12):1260-1265
This study evaluated a novel test strip designed to assess thiol levels as they relate to gingival/periodontal health in dogs. The simple to use strip (similar in form to a pH test strip) provides a colorimetric signal which estimates the level of thiols dissolved in oral fluid. Among several oral sites tested (left and right lingual vestibules, lower buccal vestibule, and upper buccal gingival margin), fluid from the maxillary gingival margin gave results with the best dynamic range, and its thiol levels correlated well with several oral health parameters (Pearson coefficients between 0.55 and 0.84; P < 0.001), especially those relating directly to the gingiva. The strip, which can be used on animals which are awake, may be useful as a quick, objective assessment of periodontal health, potentially enhancing compliance for thorough examinations, and promoting earlier and better-sustained treatment programs. 相似文献