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281.
G Orton JL Ortiz K Baines G Bjoraker U Carsenty F Colas A Dayal D Deming P Drossart E Frappa J Friedson J Goguen W Golisch D Griep C Hernandez W Hoffmann D Jennings C Kaminski J Kuhn P Laques S Limaye H Lin J Lecacheux T Martin G McCabe T Momary D Parker R Puetter M Ressler G Reyes P Sada J Spencer J Spitale S Stewart J Varsik J Warell W Wild P Yanamandra-Fisher G Fazio J Hora L Deutsch 《Science (New York, N.Y.)》1996,272(5263):839-840
Earth-based observations of Jupiter indicate that the Galileo probe probably entered Jupiter's atmosphere just inside a region that has less cloud cover and drier conditions than more than 99 percent of the rest of the planet. The visual appearance of the clouds at the site was generally dark at longer wavelengths. The tropospheric and stratospheric temperature fields have a strong longitudinal wave structure that is expected to manifest itself in the vertical temperature profile. 相似文献
282.
Sergey Hegay Mulatu Geleta Tomas Bryngelsson Abdybek Asanaliev Larisa Garkava-Gustavsson Helena Persson Hovmalm Rodomiro Ortiz 《Genetic Resources and Crop Evolution》2014,61(3):555-566
Common bean (Phaseolus vulgaris) is an important export crop in Kyrgyzstan since the end of the twentieth century. Genetic diversity analysis of common bean populations is useful for breeding programs, as it helps to select genetic material to be used for further crossing. Twenty-seven common bean accessions were analyzed using 13 qualitative morphological traits. In some cases, obtained morphological data were combined with previously published results based on microsatellite markers. The similarity matrices generated from the molecular and morphological data were significantly correlated (r = 0.49, P < 0.01). Cluster analyses based on Dice’s similarity coefficient were constructed based on morphological data and the combined data set of morphology and microsatellite, and both grouped the 27 accessions according to their origin: 15 belonged to the Andean and 12 to the Mesoamerican gene pool. On average, the Andean accessions were less diverse than the Mesoamerican accessions. The average diversity based on the Shannon diversity index for the 13 qualitative morphological traits was 0.05. Overall, this study revealed that qualitative morphological markers are efficient in assigning modern cultivars to their gene pools of origin. 相似文献
283.
Administration of exogenous hormones in ovulatory and embryonic response in Pelibuey sheep 下载免费PDF全文
A García‐Salas C Cortez‐Romero J Salazar‐Ortiz J Arroyo‐Ledezma VM Ruíz‐Vera H Vaquera‐Huerta J Gallegos‐Sánchez 《Reproduction in domestic animals》2017,52(3):446-451
The objective of this study was to evaluate the effect of two sources of commercial porcine pituitary‐derived follicle‐stimulating hormone (pFSH) and pFSH—porcine Luteinizing Hormone (pLH), including equine chorionic gonadotropin (eCG), in ovulatory and embryonic response in Pelibuey sheep. Twenty‐four Pelibuey sheep were used and were assigned randomly to four treatments (n = 6): (T1; 200 mg pFSH‐Folltropin®); (T2; 200 mg pFSH + 300 UI eCG‐Folligon®); (T3; 250 UI pFSH/pLH‐Pluset®) and (T4; 250 UI pFSH/pLH + 300 UI eCG). The interval of hours from withdrawal of the device to the beginning of oestrus (BO) was lower (p < .05) in sheep treated with eCG (T2 = 8.0 ± 1.4 and T4 = 10.0 ± 2.8) than in those without eCG (T1 = 12.6 ± 0.6 and T3 = 20.6 ± 2.4). The ovulatory rate (OR) was higher (p < .05) in T1 = 15.5 ± 2.8 and T2 = 15.6 ± 1.4, compared to T3 = 8.1 ± 3.2 and T4 = 11.8 ± 2.8; a significant difference was not shown between them (T1 vs. T2 and T3 vs. T4) when including eCG. The number of non‐fertilized oocytes (NFO) was lower (p ? .05) in T1 = 0.8 ± 0.4 and T3 = 1.8 ± 1.8, compared to those that included eCG (T2 = 6.3 ± 2.4 and T4 = 2.1 ± 1.2). The number of transferable embryos (TE) was higher (p < .05) when FSH was applied (T1 = 5.8 ± 1.1), compared with (T2 = 2.6 ± 1.1, T3 = 2.3 ± 1.4 and T4 = 2.8 ± 1.5). The commercial treatments (pFSH or pFSH‐pLH) in combination with eCG did not improve OR, NFO and TE. However, the exclusive pFSH (Folltropin) treatment presented a higher OR, lower number of NFO and higher number of TE. 相似文献
284.
Identification of sperm morphometric subpopulations in cooled‐stored canine sperm and its relation with sperm DNA integrity 下载免费PDF全文
The aims of this study were to (i) identify different morphometric subpopulations in cooled‐stored canine sperm and their patterns of distribution during cool‐storage for up to 240 hr and (ii) determine whether or not morphometric sperm subpopulations (sP) are related to sperm DNA integrity. For that purpose, morphometric parameters were analysed by computer‐assisted sperm analysis (CASA) and sperm DNA fragmentation (sDFi) using the sperm Halomax test. Four morphometric sperm heads subpopulations were identified: sP1 (large and rounded), sP2 (large and elongated), sP3 (small and rounded) and sP4 (small and elongated). sP1 was the most predominant subpopulation for up to 72 hr and thereafter sP3 increased progressively. sDFi increased after 48 hr of cool‐storage. Although sP3 showed a positive correlation with sDFi, and both increased over time, it could not be ensured that only the sperm with fragmented DNA are accumulated in sP3. In conclusion, sP3 and DNA fragmentation increased progressively during cool‐storage, becoming possible indicators of sperm damage. However, it cannot be concluded that sP3 only contains sperm with fragmented DNA. 相似文献
285.
Kimberly L Kanapeckas Te‐Ming Tseng Cynthia C Vigueira Aida Ortiz William C Bridges Nilda R Burgos Albert J Fischer Amy Lawton‐Rauh 《Pest management science》2018,74(6):i-i
The cover image, by Kimberly L Kanapeckas et al., is based on the Research Article Contrasting patterns of variation in weedy traits and unique crop features in divergent populations of US weedy rice (Oryza sativa sp.) in Arkansas and California, DOI: 10.1002/ps.4820 . Photo Credit: Amy Lawton‐Rauh.
286.
- The coastal marine protected ecosystem at Punta Coles (as a part of the Reserva Nacional de Islas, Islotes y Puntas Guaneras) is located in a highly exploited area in southern Peru and contains several commercial, bioengineering and other benthic species.
- Pre-image population analysis was used to estimate the transient values of intrinsic growth rate (r) based on biomass and density time series as a proxy of productivity to assess the effectiveness of protection.
- The outcomes obtained showed that the gastropods Concholepas concholepas, Fissurella latimartiginata and the tunicate Purya chilensis showed a reduction of productivity during recent years, whilst the sea urchin Loxechinus albus, the barnacle Balanus laevis and the bivalve Semimytilus algosus showed an opposite pattern. Several species exhibited a chaotic dynamic, coinciding with the highest productivity values. In 2016 and 2017, several species exhibited a reduction of their abundance which could be delayed responses explained by changes in oceanographic conditions (reduction of coastal upwelling), La Niña event and illegal harvest.
- The above notwithstanding, the results suggest that effective protection of benthic species in the protected ecosystem of Punta Coles have been partially accomplished. Therefore, this work could be considered a baseline study, permitting the subsequent monitoring of productivity of the main species inhabiting the coastal area of Punta Coles.
- Pre-image population analysis could be used as a complimentary analytical tool since it enables the evaluation of transient population parameters (e.g. productivity) thus aiding population management, conservation and monitoring decisions.